Toolik Field Station Book


Greetings! The text and pictures for the Toolik Field Station book have continued to grow and multiply.  Now I need more input from all of you who remember the Barrow history or have worked at Toolik and have stories and photos to share or ideas on how to improve the present text and pictures.  Also, some of the necessary science that is mere description still needs to be written – of course, I chose in Chapter 12 of this book to summarize long-term and experimental lake ecology (from Chapter 8 in Hobbie and Kling (2014)) as an example.  If your comments support this approach, then chapters on experimental results from tundra, streams, and springs still need to be written.  Alex Huryn has agreed to write up a section on springs and has been added as an editor.  Who will work on the other chapters?

The building of the Dalton Highway in 1975, from the Yukon River to the Arctic Ocean, opened the wilderness of northern Alaska for explorations of the plants and animals, tundra, streams, and lakes.  Results of these studies are well published in thousands of scientific papers and several books.  However, there is another interesting set of stories that deserve publishing; these are about adventures carrying out North Slope research before the road was built, about how scientists interacted with the animals including ground-squirrels, wolves, and grizzly bears, and about how the Toolik Field Station grew from ten tents to a major international laboratory for arctic research.  

Please look at the material in this document and send comments and additional stories about building a research station and observing interesting nature in this arctic wilderness.  While the document cannot be changed online, better pictures and text improvements are welcome (send to sends e-mail)) and, if suitable, will be included by the editors.

John E. Hobbie, M. Syndonia Bret-Harte, and Alex Huryn


1.  Introduction

2.  Early Research 1882-1981: Support from Navy and Air Force

3.  Lake Studies Greenland and Lake Peters 1957-1961

4.           A Year of Research at Lake Peters

5.           The IBP Tundra Biome at Barrow: 1970-1974  1

6.           Pipeline Road and Alyeska Toolik Construction Camp:  History and Impact on Regional Ecology  1

7.           Move to Toolik Lake 1975; Project RATE, Man and the Biosphere; Toolik up to 1983  1

8.           Facilities at the Toolik Field Station 1976 to 2020  1

9.           Ecology of the Toolik Region and Unbelievable Interactions  1

10.  Terrestrial Ecology 1

11.  Stream Ecology  1

12.  Lake LTER Chapter  1

Chapter 13.  Arctic Springs: A Rare Ecosystem    1

Image Galleries

1 Introduction
2 Early Research
3 Lake Studies : Greenland and Lake Peters 1957-1961
4 Overwinter
6 Pipeline Road
7 Move to Toolik
8 Facilities at Toolik
 9 Ecology of Toolik Region
10 Terrestrial Ecology
11 Stream Ecology
12 Lake Chapter
13 Arctic Springs


Figures - Introduction

We first describe the early research in Arctic Alaska beginning with the climate measurements at Barrow for the International Polar Year in 1882 and several expeditions in the early 1900s looking for undiscovered islands in the Arctic Ocean north of Alaska (Fig. 1.1).  One of these early explorers set up a camp along the northeastern coast of Alaska and published the earliest permafrost observations (Leffingwell 1919).  Shortly thereafter, the U.S. became concerned about the change-over to fuel oil for their ships and in 1923 the government set up four Naval Petroleum Reserves; one of these (NPRA in Fig. 1.2) is a very large region of northern Alaska called PET 4.  Serious military-funded exploratory oil searches began in 1943; a result was a large-scale logistics base at Barrow.  Taking advantage of this Naval base, a small Naval Arctic Research Laboratory (NARL) was set up in 1947 at Barrow.  This Naval Research lab flourished until 1980, with hundreds of biological and ecological studies, mostly carried out at the laboratory or close to Barrow (Fig. 1.1, Fig. 1.2).

One of the few projects away from Barrow was begun in 1958 when a joint U.S. Air Force and U.S. Geological Survey (USGS) research site was set up at Lake Peters at the edge of the Brooks Range (Fig. 1.3).  The NARL took over air and material support of the Lake Peters site for several summers and one overwinter.  The first year-round study of the physics and algal productivity of an arctic lake was carried out along with projects on ice crystallography, on birds, and on mammals.

At Barrow, a spacious, modern NARL facility was constructed in the late 1960s.  In the early 1970’s, a National Science Foundation (NSF) project used this facility for research called the Tundra Biome.  The theme of the project was ecological productivity and its controls in tundra and arctic ponds.  This project was a part of the International Biological Program (IBP), in which the U.S. contributed detailed studies of the productivity of six biomes, Desert, Grasslands, Deciduous Forest, Coniferous Forest, Tropical Forest, and Tundra.  At Barrow, many terrestrial and aquatic ecologists carried out field studies (1971-1973) as part of the IBP. These scientists then spent the summer of 1974 at an altitude of 2900 m at the Mountain Research Station of the University of Colorado’s Institute of Arctic and Alpine Ecology where they worked on two scientific books about the arctic research of the IBP.  In addition to the books, The Tundra Biome Project produced hundreds of papers and was a strong demonstration of the value of a relatively large number of scientists working together to study productivity and its controls.

Toolik Site Chosen in 1975

The IBP Tundra Biome project ended in 1974 but scientists from that research continued field research at two new sites on the North Slope; one study led to the founding of the Toolik Field Station (TFS) in 1974.  This year marked a tremendous change in how research was carried out in arctic Alaska.  Instead of flying out to field sites by expensive small planes, scientists now could travel from Fairbanks by truck on a new road that supported construction of the oil pipeline.

The Toolik Field Station is located at 68° 38’N, 149° 36’W, at an elevation of 719 m.  It lies in the middle of the North Slope of Alaska, an arctic wilderness stretching for 1100 km east to west (200,000 km2) (Fig. 1.2, 1.3), where all rivers and streams flow north into the Arctic Ocean.  The North Slope has three regions: Coastal Plain, a flat region along the seacoast, Foothills, the middle region with rolling hills where TFS is sited, and Mountains, a southern region stretching from the northern edge of the mountains to the middle of the Brooks Range.

The next part of the story is the construction of a modern research facility and transformation of the TFS to a year-round station.  With these facilities, long-term, multi-year experiments could be carried out as well as various ecological and physiological measurements in streams, lakes, and tundra.  Finally, we present scientific description of arctic ecosystems near the field station and predictions of their response to a changing climate.   The detailed scientific results of hundreds of papers are summarized in books by Reynolds and Tenhunen (1996), Hobbie and Kling (2014), and Huryn and Hobbie (2012).  However, these scientific reports do not capture the thrill of living in the middle of an arctic and that is that the wilderness location of the station led to wonderful adventures and the adventures of scientists and staff about seeing, sometimes very closely, arctic animals such as caribou, grizzly bear, and peregrine falcons; these exciting stories are included in this new book.

2.Early Research 1882-1981: Support from Navy and Air Force

Figures Early Research

First International Polar Year 1882

Under the jurisdiction of the U.S. Army Signal Corp, the United States contributed two stations to the First International Polar Year (IPY) in 1882-1883; one research camp was set up at Point Barrow (Fig. 1.2), the northernmost point of Alaska’s North Slope, and the other was on Canada’s Ellesmere Island (Ray 1884).   Worldwide, there were 14 arctic camps for this IPY from 11 countries (Taylor 1981).  The Barrow station collected detailed climate data as well as magnetic and auroral observations.

Leffingwell’s Work on Permafrost 1908--1917

After the IPY in 1882, there was little scientific presence on the North Slope until the detailed observations of Ernest Leffingwell on permafrost (Leffingwell 1919).  Leffingwell led an adventurous life.  Born in 1875, he graduated from Trinity College in Connecticut, served in the U.S. Navy during the Spanish-American War, and fought in the Battle of Santiago in 1898.  He then studied geology at the University of Chicago (and played on the Chicago Maroons football team) but never finished his PhD thesis.  One of the geology professors at Chicago was T.C. Chamberlin, a former president of the University of Wisconsin, a member of the Peary Auxiliary Expedition of 1894 that traveled to northwestern Greenland, and the scientist who named the Wisconsin (11-75,000 years ago) and Illinoian (130-190,000 years ago) glacial periods.  Leffingwell became interested in the Arctic and chose to visit Alaska and co-fund an expedition of his own (see Ejnar Mikkelsen in Wikipedia) to explore for islands in the Arctic Ocean (Fig. 2.1).   In 1905 his wealthy father contributed $5,000 (equivalent to $147,000 today), to fund half of the cost (Mikkelsen et al. 2015).  The 1906-1908 expedition was an ill-fated trip to explore the Beaufort Sea north of Alaska (Fig. 2-1) using the sailing ship The Duchess of Bedford.  The ship was wrecked in the ice and Leffingwell constructed a cabin on Flaxman Island from the wreckage, near the Canning River Delta (Fig. 2.1B).

Leffingwell lived in the cabin over the next seven years, made some trips back to California, used his private yawl Argo, and mapped some 250 miles along the coast and inland along the Canning River (see Ernest Leffingwell in Wikipedia); in his inland trips he traveled the hard way by foot, small boat, and dogsled.  He said, “A good dog will pack half his weight all day, but he does not enjoy it.”  In a column written for the University of Alaska’s Geophysical Institute, Ned Rozell stated that Leffingwell’s favorite meat was caribou, but in lean times anything would do.  “Seal and polar bear are not appetizing when one has recently eaten caribou,” Leffingwell wrote, “but after a period without meat of any other kind for comparison they form a welcome addition to the table.”  Leffingwell also shared the local Natives’ preference for fur clothes over wool.  “At first the (fur) clothes are uncomfortably warm, so that one perspires freely, but after a few months the skin becomes accustomed to the heat, so that a man in good physical training will perspire much less than when dressed in woolen clothes”.  About polar bears he said, “Locally they are regarded much as wolves are in cattle country.”

In his monumental publication for the U.S. Geological Survey, Leffingwell (1919) was the first to scientifically describe the presence and influence of permafrost, the permanently frozen ground that covers the North Slope.  Rozell says that the publication reads like a manual on how to live and perform science in the far north. Leffingwell also helped to identify the oil potential of the North Slope and named the 3rd highest mountain in the Brooks Range after T.C. Chamberlin. He retired to his family’s California fruit farm in 1917 and lived to see Neil Armstrong step on the moon, passing away in 1971 at the age of 96.

Stefansson Describes Leffingwell

Another explorer of this period who met Leffingwell was Vilhjalmur Stefansson, who was the last to discover new islands in the Arctic. In his book, The Friendly Arctic (1953 edition), he tells about his five years in northern Canada and Alaska and describes a 1912 meeting with Leffingwell on Flaxman Island on the Alaskan coast. “Here we found Leffingwell in the house, built in 1907 from the wreck of his ship The Duchess of Bedford.  . . . The house had been added to and was rather palatial for those latitudes.  He had an extensive library in several languages, one of his rooms was furnished with a roll-top desk, and altogether the equipment ranged from the sumptuous almost to the effete. . . While the outfit was elaborate it was in the main a relic of the times when he had been a tenderfoot and his tastes had not yet been turned towards simplicity by his experience in the North.  The first year he was there he had “lived well”, as the saying goes. He had no end of variety of jams and marmalades, and cereals and food of all sorts.  At the end of the year, he complained on arrival in San Francisco . . . that he had had a very hard time.  He had been several weeks without butter and so many more weeks without something else.  How his taste had altered in the seven years since then was best shown when McConnel volunteered to cook breakfast the next morning and suggested that the breakfast might consist of oatmeal mush and hot cakes.  This struck Leffingwell as an extraordinary suggestion and the genuineness of his surprise was clear from the tone in which he said, “Mush and hot cakes!  If you have mush what’s the use of hot cakes, and if you have hot cakes what’s the use of mush?”  This principle is the essence of dietetics in the North.  The simplicity of living on few foods contributes not a little to the charm of the North.”

1944 U.S. Navy’s Oil Needs, ONR at Umiat and Barrow 1923--1981

As described in Chapter 1, the U.S. designated a region as an oil reserve called PET 4 in 1923; in 1944, a World War II oil shortage prompted the start of a PET 4 oil exploration.  By the end of that year, a large camp was under construction at Pt. Barrow.  From this 1944 start until 1953, 80 holes and test wells were drilled in several regions where natural oil seeps occurred.  Three oil fields and seven natural gas fields were identified but these were not productive enough for later development (Schindler 2001).

In 1947, the Office of Naval Research (ONR) decided to expand their arctic research effort and take advantage of the well-established Naval facility at Barrow; seven scientists were sent to Barrow to begin the Naval Arctic Research Laboratory (NARL). Easily constructed structures called Quonset huts were used to house the laboratory (Fig. 2.3); this laboratory grew over the years and was the home base for hundreds of scientists from many universities.  The ONR funded a wide variety of scientific research, almost all at Barrow, through subcontracts to universities from the Arctic Institute of North America (AINA).  While most research was carried out near the coast at NARL, there was also research at major sites along the coast, including Barrow, Wainwright, Pt Lay, Pt Hope, and Kaktovik, on drifting ice in the Arctic Ocean, and even some research at terrestrial sites away from the coast (Anaktuvuk Pass, Atqasuk, Noluck Lake, and Lake Peters).  Much of the research was ecological and geomorphic – the Arctic Program and the Geography Branch of ONR was very enlightened under the leadership of Dr. Max Britton and supported a wide range of ecological projects (Shaver 1996, Hobbie 1997, Norton 2001).  Britton said that to the Navy “fell a first responsibility, and what might be considered a moral commitment, to learn both how to use the environment and how to protect it.”  The NARL at Barrow was headed by Dr. Max Brewer from 1956 to 1970.  All the NARL scientific history and research is described (Laursen et al. 2001) in a large book edited by D. Norton (2001) and titled “Fifty More Years Below Zero: Tributes and Meditations for the Naval Arctic Research Laboratory’s First Half Century at Barrow, Alaska”.  This book describes research and events from 1947 until the 1960s (Laursen et al. 2001).  The laboratory ended operation in 1981 and the facilities were taken over by Ilisagvik College, a tribal college.

Freshwater ecology at Barrow was investigated several times; Jaap Kalff (later a McGill University professor) carried out his PhD research (Indiana University) on the shallow ponds abundant near the coast while Raymond Stross (PhD University of Wisconsin) studied the zooplankton of these ponds.  Freshwater research in northern Alaska was also carried out by Dan Livingstone (PhD Yale), later a professor at Duke University, who worked from NARL in the early 1950’s.  He made the first measurements of physical conditions in deep mountain lakes (Livingstone et al. 1958) and studied pollen profiles from water near Umiat (Livingstone 1955).  Dan relied on single-engine float planes from Barrow.  Charles E. Carson from Iowa State University studied the origin and orientation of thaw lakes of the coastal plain; most were close to Barrow but some near the Kuparuk River in northeastern Alaska (Carson and Hussey 1962).   John Hobbie began studying two mountain lakes with U.S. Air Force research funds in 1958 and was supported by light planes from NARL and by The Arctic Institute and NARL in three later years.  See Lake Peters section in Chapter 3.

At Barrow, studies were made of nutrient recovery (Frank Pitelka and Arnold Schultz), the thaw lake cycle (Britton 1957), lemmings, (add references), and plant ecology (references). In other northern Alaska areas, Tom Cade studied the peregrine and gyrfalcon populations along the Colville River and Jerry Brown (Rutgers University) studied soils of the eastern Brooks Range.

U.S. Air Force Arctic Research 1951-1958

The U.S. Air Force had their own research questions about the entire Arctic region that differed from those pursued at the Naval Lab.  It was realized that little was known about the features of the lands surrounding the Arctic Basin; for this reason, the U.S. Air Force funded the Physical Research Laboratory of Boston University to correlate various terrain features with aerial photographs (Tedrow 2005) so that tundra conditions in similar regions of the entire Arctic could be identified.  Because of the availability of a research camp set up for oil exploration, the decision was made to study the Umiat region.  Quonset huts (prefabricated structures of galvanized steel), weasels (tracked vehicles the size of a small car), and boats were available and in 1951 a team carried out measurements nearby (Fig. 2.4).

After discussing the ideas and first results with the United States Geological Survey (USGS), it was decided to study in 1952 a north-south transect beginning at the edge of the Brooks Range along the Kurupa River, southwest of Umiat (Fig. 2.2).  The 21-person field party, consisting of a director, a field director, two cooks, four ecologists, one field assistant, three geologists, two pedologists, three engineers, one photographer, and three military weasel drivers, departed in early June 1952, from an Air Force base in Massachusetts and flew first to the west coast and then to Umiat.  Project activity included reconnaissance studies in the Umiat area along the north side of the Colville River as well as studies along the Kurupa River.  In early July, six scientists and the weasel drivers were ferried across the Colville River in a landing craft where they made observations of bedrock geology, surficial geology, engineering and pedological properties of soils, and plant cover.

A third field season was planned that included four first timers in the Arctic, L.C. Bliss, F.H. Bormann, J.E. Cantlon, and J.C.F. Tedrow, who would all become well-known scientists.  This is perhaps an indication of the advantages of getting in on the ground floor need for new ideas and a keen eye for talent.  Field expeditions traveled both south and north of Umiat via boats, weasels, and airplane.  Measurements were made near Harrison Bay (70oN), Barrow, Barter, and other sites.  Based on all this work, D.E. Hill wrote his PhD thesis on soils at Rutgers University, six other journal articles were published, and ONR funded Cantlon and Tedrow to continue the soil and plant ecological investigations they began on this project (called the Keyes Project).  Cantlon later called the Umiat project “a secret US Air Force project on the Ecology of The Arctic Slope of Alaska”. An additional result of Tedrow’s long-term study of arctic soils was the PhD project of Jerry Brown on the North Slope (completed in 1963).  Jerry Brown later worked for the U.S. Army Cold Regions Research Laboratory and became the leader of the U.S. Arctic Biome, a massive Barrow-based NSF

Air Force McCall Glacier Research 1957-1958

The Air Force also funded research under The International Geophysical Year (IGY) in 1957—1958.  This project included research on McCall Glacier (69o20’N and 143o49’W), which is 25 miles east of Lake Peters and 75 miles from the Canadian border (Fig. 2.5).   The research included temperature measurements within the glacier, a mass balance estimate, and climate studies (Weller et al. 2007).

The IGY McCall Project began in May 1957, with two flights from Fairbanks by US Air Force twin-engine C-119 “Flying Boxcars”, planes with a large cargo space and cockpit mounted between two slender fuselages (Weller et al. 2007).  More than 30 tons of fuel and scientific gear were air-dropped onto the glacier, including parts for five Jamesway insulated huts (Fig. 2.6).   Pictures of the loss of glacier mass from 1958 to 2007 (Fig. 2.7) illustrate the dramatic retreat of Arctic glaciers over this short period

3.  Lake Studies Greenland and Lake Peters 1957-1961

Figures - Lake Studies: Greenland and Lake Peters 1957-1961

Dartmouth Arctic Connections: Resolute Bay in the Canadian Arctic

Except for the Umiat-based research, there was little ecological research inland from the coast before 1975 because travel outside of Barrow was difficult and costly.  It did occur occasionally as illustrated in the way that John Hobbie ended up carrying out his research on the North Slope.  In 1957 the U.S. Air Force Cambridge Research Center (AFCRC) funded Dartmouth College for a project on the strength of lake ice near Thule Air Force base in Greenland (Fig. 1.1).  This project was continued at Lake Peters, Alaska (Fig. 2.5), by the AFCRC, U.S.G.S. and the Arctic Institute of North America (AINA) (with ONR funds).

John Hobbie writes:  I attended Dartmouth College, where there was an active arctic research faculty; the arctic course I took was led by a group of five faculty including the famous explorer Vilhjalmur Stefansson (1879--1962) who started his career by living for a year among the Inuit in 1906.  He later sledged north for three months from Collinson Point which lies on the Arctic Ocean coast, north of Toolik Lake.  (See Chapter 2 where Stefansson describes a visit to Leffingwell.)

One result of Dartmouth’s Arctic connections was my first airplane flight - in a Canadian Air Force Flying Boxcar from Montreal to Winnipeg to Churchill to the Arctic where I spent the summer (1955) working in a warehouse at the US/Canada Weather Station at Resolute Bay (latitude 75oN, in Canada) (Fig. 1.1, 3.1).   This was the site of the main U.S./Canada Weather Service station in the Arctic; supplies were carried there by ship each summer for later air shipment to remote sites.  At that time in the 1950s, this installation consisted of a Canadian Air Force airfield and a variety of buildings of several government agencies including a Joint U.S.-Canada Weather Service.   Several Inuit families had been recently moved to Resolute Bay because there were abundant seals, walruses, and whales.  Five of us U.S. students cleaned warehouses during the week and explored on weekends.

And we had a remarkable experience with a polar bear chase.  The young bear (big but not quite an adult) swam from the ocean icefloes to the shore where he was suddenly chased inland by a large husky named Pogo.  The husky and the young polar bear ran at a somewhat leisurely pace over the stone-covered vegetation-less beach, while we students followed in a pickup truck.  We pursuers were soon joined be a long line of 15 or 20 curious walkers from nearby Canadian and U. S. scientific installations.  Suddenly after about a half a mile, the bear turned around, heading back to the ocean.  This return path of the bear, still followed by Pogo and the truck, was right alongside the oncoming line of workers.  Luckily, neither the workers’ curiosity nor Pogo’s persistence led to any injuries, even though Pogo had tried to keep close contact with the big white creature.  Despite our long hikes every weekend, this bear was the only live animal we saw, though we did see lots of quite fresh muskoxen tracks.

A highlight of the 1955 summer was our contact with Idlouk, one of the Inuit, who had recently been moved to Resolute Bay from Pond Inlet, an Inuit village some 369 miles to the East on Baffin Island.  David Clarke, one of the students from Harvard, had brought a gift of rifle ammunition to Idlouk from a Harvard Professor whom Idlouk had recently guided on a summer expedition.   The RCMP overseer of the Inuit did not want the ammunition transfer but eventually it happened and Idloulk invited all of us students for a tour of the Inuit village (Fig. 3.1) and a tasty dinner of walrus flipper (Fig. 3.2).  It really was quite good.  An excellent book about the daily lives of the Canadian Inuit of the time was written by a young Canadian journalist, Doug Wilkinson (Wilkinson 1955); he lived with Idlouk’s family on Baffin Island in 1954 and was treated as a son, taking part in all the hunting and traveling.  The author says, “This is a difficult and critical time for all Eskimos in Canada.” And criticized the government’s treatment of the Inuit; “A better way to create a group of second-class citizens in Canada, I do not know.”  In 1993, the Canadian Government acknowledged that a mistake had been made because the Government had ignored a request by the Inuit to be moved back to Pond Inlet.  A 10 million (Canadian) dollar award was paid to the Inuit survivors.

Air Force Project on Arctic Lake in Greenland 1957

In 1957, I joined an expedition to northeast Greenland (77oN) (Fig. 3.3); this project eventually led to my PhD research in Alaska.  The Dartmouth College project was sponsored by Air Force Cambridge Research Center (AFCRC) and led by David Barnes, a USGS geologist devoted to studies of ice formation and crystal structure.  Dave graduated from Harvard, was on the swim team with John F. Kennedy, and spent the war years as a research assistant at The Woods Hole Oceanographic Institution studying underwater explosions.  His USGS-Air Force Project in 1957 was to investigate whether the ice on Anguissaq Lake, a lake approximately 100 km north of Thule Air Force Base (latitude 76oN), was strong enough to support an emergency landing of a jet fighter or bomber (Barnes 1958).  This lake, 187 m deep, has a permanent ice cover, a rarity for the Arctic.  This permanent ice cover could exist because the lake lies at the edge of the Greenland Ice Sheet (Fig. 3.4) and between coastal ice-free hills and an ice-free rocky island out in the ice sheet (see Fig. 3.5).  The unique feature that caused the permanent ice cover was the under-ice geologic topography which allowed the ice sheet to enter the lake from each of its two ends while the lake and its ice cover remained in place.

I had just graduated Dartmouth and was hired to assist and cook on the expedition probably because I had spent four summers backpacking and cooking for the Appalachian Mountain Club’s huts in the White Mountains.  However, after we stayed in the officer’s quarters at Thule for several weeks, an Air Force helicopter moved us out to the research camp; we lived in the field for two months where our meals consisted of Army C rations (Combat), individual meals in small cans.  That summer my cooking expertise was limited to warming small cans and baking a cake for dessert in a make-shift oven on top of a Coleman two-burner gas stove.

To test the ability of the floating ice sheet to hold up an airplane we used a chain saw mounted on a sled with a nine-foot-long bar holding the chain (Fig. 3.6, 3.7).  The bar rotated downwards and was moved to cut out a peninsula of ice.  Using measuring instruments, we either push down or pulled up the end of the peninsula until the ice cracked – the carefully measured amount of pressure to break this peninsula of ice measured the ice strength.

The answer to the question about the strength of the lake ice was that, yes, the 3.4 m thick icesheet was strong enough to support any size of airplane; however, there was a severe complication.  The upper one-third of the ice sheet melted each summer while each winter new lake ice froze at the bottom of the ice sheet.  But an uneven melt was caused by dirt on the ice that accumulated irregularly over many centuries from air-borne dust and also from dead fish, arctic char that lived and died in the lake under the ice sheet.  These dead fish floated up and were incorporated into the ice sheet.  Then they moved through the ice sheet as the top meter of the ice sheet melted each summer.   As a result, the ice became very rough and was not suitable for a runway.

Air Force Ellesmere Ice Shelf, Canada, and Lake Peters, Alaska 1958

This Dartmouth-USGS-AFCRC project was to be enlarged and moved the next summer, that is, 1958, to northern Canada to study the Ellesmere Ice Shelf.  This major effort was led by glacial geologist Bill Holmes, a USGS scientist working for AFCRC; I was to take part as a graduate student at the University of California, Berkeley.   Now, in 2020 when I read about this Ice Shelf, the past tense is always used because there has been a drastic reduction in size of the Ice Shelf.  Wikipedia says, “The former Ellesmere Ice Shelf was the largest ice shelf in the Arctic, encompassing about 3,500 square miles (9,100 km2) of the north coast of Ellesmere Island, Canada.” Almost of it has now broken apart and floated off into the Arctic Ocean.  However, in early 1958 the AFCRC-USGS-Dartmouth project was all ready to go north, but at the end of March it was suddenly decided that plans had to be changed.  This probably occurred when the Strategic Air Command (SAC) took over the Thule Air Force base at the height of the Cold War and decided not to support research on ice processes.

I was suddenly informed that the project was relocated across the entire continent to Lake Peters in the Brooks Range of Alaska (69°N, 145 °W, Fig. 1.3) with Bill Holmes as the project leader.  This new Alaska project included the history of ice advances, ice crystallography, and the limnology of Lakes Peters and Schrader.  This was the start of my own research that included work (1958-1961) on these two lakes which lie at the northern edge of the Brooks Range and 200 km northwest of Toolik Lake (Fig. 3.8, 3.9, 3.10, 3.11).  The research at Lake Peters was first supported by AFCRC and the USGS.  In the following years support came to include ONR, NARL, and the Arctic Institute of North America.

In early June of 1958, food and supplies to construct a small building were to be flown in from Fairbanks and landed on the lake icesheet with a C-46 two-engine cargo plane (Commando) from Wein Alaska Airways.  These aircraft were developed in WWII to transport military goods from India over the Himalayas to China; it had large super-charged twin-engines that could carry heavier loads than a C-47.  To test the ice safety at Lake Peters, a ski-equipped light plane flew north from Fairbanks on 8 June (pilot plus Bill Holmes, Major Frank Riddle, and me).  We first landed on the McCall Glacier, where there was a 1957-1958 International Geophysical Year (IGY) project (Fig. 2.6, 2.7), then landed on the ice of Lake Peters (Fig. 3.11), where the team thought the ice was strong enough for a cargo plane and reported back to Fairbanks.  Hours later the C-46 landed but, unfortunately, as soon as the plane came to a stop the wheels punched through the ice (Fig. 3.12, 3.13, 3.14) and the engines and propellers hit the ice.  Evidently the ice was still thick enough but had warmed so the crystals were not well connected (see ice melting details in Hobbie 1984).   Most of the scientific staff stayed at Barter Island on the ocean coast for a week and then were flown to Lake Peters in a Super Cub plane piloted by 18-year-old Rich Wein (Fig. 3.15).  This was a dramatic beginning to four years of research at Lake Peters.  But the drama continued all summer.

The C-46 sat on the ice for several weeks and the cargo was moved to the nearest shore to set up the camp.  Then Wein Airlines hired two of their part-time mechanics, a Fairbanks bartender and Rex Avakana (Fig. 3.16) from Barrow, to get the airplane flying again.  They first placed empty oil drums under the wings so that when the ice did melt at the end of June, the plane floated (Fig. 3.17A).   They then towed the plane three miles to the north end of the lake (using my small 4½ HP research boat) and winched it up onto the flat tundra of the delta between Lakes Peters and Schrader (Fig. 3.17B).  Although the original plan was to wait until the winter ice cover had formed, a high wind in September allowed the plane to take off over the swampy irregular tundra, an extremely risky thing to do.  The C-46 safely returned to Fairbanks and was parked at the airport for years.

Bill Holmes Project Director, Major Frank Riddle Manager of Lake Peters Camp

The 1958 field season began with the C-46 plane accident, but this was just the beginning of an unbelievable three months.  Bill Holmes of the USGS and AFCRC was the project director investigating the extent of the past glaciers (see later photo in this chapter); he had been the leader of the aborted project on the Ellesmere ice Shelf.  Bill had been a B-17 chief pilot in WWII.  On New Year’s Day, 1945, his plane lost three engines while bombing Berlin.  The final engine failed just as the low-flying plane reached no-mans-land at the French border.  Bill brought the plane down for a pancake landing (no landing gear) with no injuries; the crew ended up walking to a chateau occupied by British troops.  He received the Distinguished Flying Cross medal for this adventure.

Major Frank Riddle was the camp manager and radio operator, a retired veteran of the Canadian Army Signal Corps (Fig. 3.18).  He first went to the Arctic in 1919 when he was sent to spend a year collecting weather data at Aklavik (68oN), near the mouth of the Mackenzie River in Canada.  This was before airplanes were available in the Arctic, and Frank traveled on a boat down the Mackenzie River to reach his station.  He hand-carried several giant radio tubes to radio back storm information.  During the next years he advanced in the Canadian Army and when he was a sergeant in 1932, he took part in a famous manhunt.  Wikipedia states the following.  “In 1931, Albert Johnson, later known as the “Mad Trapper of Rat River” moved into the area. A complaint was made to the Royal Canadian Mounted Police (RCMP) post in Aklavik, and the two Mounties attempted, unsuccessfully, to talk with him concerning trap-line tampering.  A second attempt was made a few days later, after a search warrant had been obtained, and Johnson shot and wounded one of the RCMP. This sparked a 48-day manhunt. This incident is famous for introducing the airplane and communications radio as tools to help track a person.  Frank took part in the manhunt on the ground traveling by dogsled at -40o (C and F temperatures).  Finally, after the fugitive was spotted by an airplane pilot, Frank and two RCMP officers had a shootout with the mad trapper on a frozen river; the mad trapper and one RCMP officer were killed on 17 February 1932.   Several books tell the story of the manhunt (e.g., D. North (2005) The Mad Trapper of the Rat River).  Later, in World War II, Frank fought in Italy as a major in the Canadian Army and after the war he led army exercises in the Arctic.

The camp was located at the tip of an alluvial fan extending into Lake Peters (Fig. 3.19).  Lake Peters and Lake Schrader were once a single lake but thousands of years ago the stream entering at mid-lake deposited material into a delta that now separates the two lakes (Fig. 3.20).   Lake Schrader is larger and deeper than Peters (Fig. 3.21).

Migration of the Porcupine Caribou Herd

On July 4-5, 1958, while the camp was being built, we witnessed one of the largest mammal migrations on Earth.  A migrating caribou herd with many tens of thousands of animals entered the Lake Peters valley from the northwest and moved south along the lakeside across from the camp.  The herd then forded the large stream entering the lake from the south (Fig. 3.22) and soon moved north.  As the caribou moved along the edge of Lake Peters, small groups would suddenly swim across the lake or dash up the hillside, apparently following a leader.   Back at our camp in the evening, we waited for the front of the herd to appear over the high center of the alluvial fan.  Suddenly a blonde grizzly bear appeared at the top of the fan and walked over to the edge of steep mountains to hide behind a large boulder (Fig. 3.23) while the streams of caribou continued to increase and soon covered the fan surface (Fig. 3.24).  They stopped moving and spread out to graze (Fig. 3.25).  As we watched, the bear soon reappeared and ambled along to the north and out of sight.  The caribou calmly opened a path some hundred feet wide or so for the bear but did not appear at all excited.  Later, around midnight, some of us at the camp walked to the top of the fan and the caribou also opened a lane for us.

This was the Porcupine Herd, or perhaps a major part of this herd, which is one of four separate herds on the North Slope.  These herds total around 800,000 animals.   We found it difficult to estimate the number of animals in this part of the Porcupine Herd but estimates in other years have ranged from 123,000 (2001) to 218,000 (2017) animals for the entire herd.  Lake Peters is 4 miles long and the herd surrounded the lake so there certainly were many tens of thousands of caribou.  The animals of this herd spent the winter south of the Brooks Range subsisting on lichens in the forests near the Alaska-Canada border.  In the spring the herd traveled across the border into Canada and then north to the tundra lowlands now in ANWR (Arctic National Wildlife Refuge) directly north and northwest of Lake Schrader (Fig. 1.3, 3.26).  Here the caribou gave birth to the year’s calves.  In 1958 we could see the herd spread out over 60 miles as we flew back and forth from Lake Peters to Barter Island immediately after the plane incident described above.  In late June and early July, they formed large herds and moved through the foothills and passes of the Brooks Range eventually reaching their winter range (Fig. 4.27).  The animals travel 800 miles in their annual migration, the longest terrestrial migration in the world.   I have read that as the animals move, there is about one death per mile of travel.  In fact, I later found several drowned caribou along the lake shore.

A recent picture of a caribou herd (Fig. 3.27) is an incredible view of a large group in the Brooks Range; it illustrates the difficulty of estimating numbers in a constantly moving population.   These large herds also leave persistent scars on the tundra as seen in a picture taken just north of Lake Schrader (Fig. 3.28).

Famous visitors

One late summer visitor in 1958 was Frank Whitmore, the Director of the U.S. Geological Survey. In Fig. 3.29, he is standing next to a wide tundra slump where thawing permafrost has led to a surface movement of soil and meltwater down the hill and into the lake.  The summer of 1958 was extraordinarily warm and was the only summer, of four I observed, when these slumps occurred.

Near the end of August1958 the camp was visited by a uranium millionaire named Vernon Pick who lived in California and was flying his very large single-engine float plane (a De Havilland Otter) on a sheep-hunting expedition (Fig. 3.30A).   Vernon struck it rich in Utah in the early 1950s and sold the mine for $9 million and a $250,000 Otter airplane.  His net of $6 million is equivalent to $16 million today. In Fig. 3.30B, Vernon is shown with Bill Holmes, the project director.  The Bombardier tractor that Bill used over the tundra is shown in Fig. 3.30C.  Vernon also had a somewhat dangerous sense of humor—dangerous for me.  On one of his flights back to Lake Peters, he flew over much the lake at a height of about 15 feet.  I was sitting in my small motorboat returning to camp from Lake Schrader and Vernon came behind me; I could not hear the plane because of my outboard motor so I was very surprised to suddenly hear the engine roar as the plane passed just a few feet overhead.   He did give me a ride back to Fairbanks – such ‘hitchhiking’ was a common way to get back to civilization for a few days (?).

Massive Air-Search for Missing Alaska Territory Official

The last unexpected visitor at Lake Peters that summer of 1958 was the head of the U.S. Fish and Wildlife Service in Alaska, Clarence Rhode (Fig. 3.31), who arrived on 21 August along with his son and another game warden.  The given purpose was to visit the science project, but we wondered if he was also checking whether we were eating mountain sheep out of season.  After a short stay, their float plane took off and briefly landed on Lake Schrader before they flew away.  We later found out that we were the last to see them; they were never heard from again.

A few days after the disappearance, Frank Riddle saw a single caribou swimming across Lake Peters and took a boat out to harvest it as the camp was short of food.  Just after he had killed the animal and had pulled it into the boat, he heard planes, and six search planes from the Fish and Wildlife Service soon landed.  No one asked him about the caribou.  Our camp soon became the early center of an intensive air search with 260 people and 28 airplanes eventually taking part.  The searchers spent more than 2,000 hours of flying time and covered an area greater than California and Oregon combined failed to find the plane with its 3 passengers.   The mystery persisted for 19 years until a hiker spotted a patch of orange metal from the fuselage (Fig. 3.31) near the top of a mountain pass close to the Ivishak River, some 50 miles southwest of Lake Peters (Wilbanks 1999, Miller 1990).

4.       A Year of Research at Lake Peters

Figures - Overwinter

Overwintering at Lake Peters

In August 1960, John recalls that he and his wife, Olivann, arrived at Lake Peters in a light plane from the Naval Arctic Research Laboratory (NARL) (Fig. 4.1) to begin a long and solitary stay observing events in these lakes year-round.  We received a delivery of fresh food and mail every two weeks; the planes landed on the water (Fig. 4.1, 4.2) with pontoons or on the ice-covered lake with wheels or skis (Fig. 4.3).    There were no flights in October or most of June when Lake Peters and lakes at Barrow were freezing or thawing.  We used a shortwave radio every afternoon to contact NARL (Fig. 4.4).  In our valley, the sun set on November 9th and was next seen again for a few minutes on February 2nd.  During the deep winter there was twilight of about 5 hours each day which was enough light for a plane to land.  A minor annoyance was that the pilot wanted to leave NARL early in the morning of a flight but the director of NARL slept late and never arrived at the laboratory until 10:30; he insisted that he had to approve every flight so the plane always arrived at Lake Peters late in the twilight period and had to fly back in darkness; fortunately, Barrow had lights permitting a night landing.

Olivann (Fig. 4.5, Fig. 4.6) took responsibility for the climate record, making three observations every day.  She also did the cooking and tutored John every evening so that he could pass the French Language qualifying test for the PhD (he had already passed the German test).  She had started a Masters degree program in English at Indiana University, where John was getting his Ph.D. for his Arctic studies. Fortunately, she had an extensive reading list to work through that winter, including Chaucer’s Canterbury Tales, Spenser’s Faerie Queene, and several Shakespeare plays. An early adoptee of remote learning!

Luckily for us, the Alaska State Library had a wonderful program for circulating books to people living in isolation.  They sent a box of excellent new books every six weeks based on our reading preferences.  For light inside the hut, we used Coleman gas lanterns and sometimes also a small and challenging electric generator that broke down periodically.  One faulty generator was returned to NARL, fixed by the manufacturer and was ready for shipment to Lake Peters when it was destroyed by a fire at the NARL shop.  In addition to our daily radio check-in with NARL and the biweekly airplane visits, we were pleased to discover that we had excellent shortwave radio reception during the winter with which we could get programs from all over the world. We particularly enjoyed the news (in English) and language lessons from German public radio (Deutsche Welle), which had begun programming in 1953.

In our main hut (Fig. 4.4), the cooking and heating stove was an unusual one that Frank Riddell bought for setting up the camp—he said that, based on his many years living in the Arctic, this stove would fit the camp need, and a plus, didn’t need electricity. It was, in fact, a cast iron tugboat stove in which the incoming kerosene entered the kitchen/living quarters in a copper tube from a kerosene barrel raised outside. This tube then passed into the stove and through the fire box, where the kerosene was volatilized; finally, the kerosene, now a gas, sprayed into the fire box. This stove roared continually, a rather reassuring sound, especially when we could hear the cold Arctic winds howling outside our wooden shelter. This single stove provided a very hot cooking surface, an oven for baking, a fire box, and heat for the two rooms, although the bedroom walls sometimes had ice patterns crawling up a foot or so above the floor.

One January night, when we had returned after a month of semi-civilized living at Barrow, Olivann woke up to an unexpected sound: the sound of silence.   She instantly poked John: “John, John, the stove’s out!”  He got up to investigate the problem, and she got the egg carton from the cupboard to bring it back to bed, where she could keep the eggs warm.

What had happened?  The outside temperature had fallen below -52oF!  No one from the Barrow NARL lab had mentioned that at 52 below Jet Fuel A-1 forms crystals and stops flowing. In retrospect, perhaps few at NARL knew this crucial fact because on the coastal North Slope it rarely gets that cold; at Barrow the coldest temperature ever recorded was -56oF.  In the Fairbanks region far south of the Brooks Range, in interior Alaska, it is often that cold; the coldest ever temperature recorded there was -66oF.

In any case, after a brief panic I was able to quickly bring some fuel oil inside the still relatively warm hut and replumb the incoming copper tubing to a new source; finally, the kerosene sprayed into the fire box and we could restart the stove, which quickly resumed its comforting roar.  Incidentally, the mountain valley at Lake Peters was much colder than the foothills and coastal plain of the North Slope.  In February 1961, the minimum temperature at Lake Peters camp was -50.3oC (or -58.5oF) while the minimum Barrow temperature for the same month was -41.7oC (or -43.1oF).

In late fall, we were surprised to find that there was a neighbor camping at the end of the lake three miles away.  Wim had recently been divorced back in the Midwest and wanted to get away from everything and everybody.  He had read about Stefansson’s adventures in the ‘friendly’ Arctic and assumed that he too could survive by hunting caribou and mountain sheep.  He hired a bush pilot to drop him off near the mountains in September and to return to pick him up the following spring.  Luckily for him, we were nearby.  I never asked him if the pilot knew that Wim was dropped off near an existing camp.   It turned out that his tent was very inadequate even though he piled up walls of peaty soil around it; he was very cold nearly all the time but also a poor hunter.  Happily, for the three of us, we were glad to offer him the use of our cabin while we de-bushed in Barrow for part of the month of December.  He took weather data for the project, and we got to enjoy the company of other scientists and eat and sleep in an almost normal style. But the greatest gift of our weeks in Barrow was the full moon. The winter full moon is perhaps even more spectacular than the famed Arctic midnight sun. As the brilliantly white, enormous moon made a slow circle low over the horizon, it made the snow-covered landscape a sight of almost magical beauty.

We had one more interaction with Wim.  One morning in November, Olivann and I were walking on the nearly snow-free lake ice while systematically measuring the depth of Lake Peters at selected intervals, when we spotted a wolf running towards us several hundred yards away.  Wim was at his camp, also saw the wolf, and immediately started to shoot at the wolf from a great distance—probably half a mile—he missed completely.  However, he did scare away the wolf; more interesting, we observed that his rifle bullets skipped over the ice several times leaving a trail just like ripples from skipping a flat rock on a quiet pond.  It appears to be a little-known fact that bullets will ricochet over calm waters and over an ice sheet; there are stories about this in Google from rifle buffs.

Late in the winter, April and May of 1961, the Lake Peters camp received resupply trips from military cargo planes.  The NARL C-47 made several flights from Barrow with food (Fig. 4.7) and the Air National Guard C-123 planes flew up from Fairbanks with fuel several times.  Most fuel was dropped in 55-gallon barrels from planes flying at a height of only a few feet (most of the barrels survived) as shown in Fig. 4.8.

One minor unfortunate occurrence overwinter was the loss of use of the camp’s tracked vehicle, a Bombardier.  This 2-person vehicle was brought to Peters at the start of cargo flights in 1958 and was used for traveling across the tundra by USGS scientist Bill Holmes (Fig. 3.29C).   He traveled north to the coastal plain and east to the Hulahula River to trace glacial histories (Holmes and Lewis 1961).  During our overwinter year, we began to use the Bombardier after the ice became safe for travel, but I was very cautious and stayed very close to the land-ice border.  But this did not work out well as I did not realize that there was a place with thin ice where at that time of year soil water was invisibly flowing out of the tip of each alluvial fan.  The Bombardier fell through this thin ice and into a foot of water at the land’s edge.  The engine was partially in the water, ice formed, and when I tried to melt this ice under a tent made of old sleeping bags, this tent caught fire.  What a mess!  So, the vehicle had to overwinter there to be rescued and repaired by Frank Riddle the following summer.  Frank did tell me that he too had dropped a tracked vehicle through lake ice and had to swim out of a deep lake.  As I found out nearly 50 years later, the summer crew in 1962 formally renamed the vehicle JOHN I to the amusement of all (this from my brother’s book (Hobbie 2009)).  Looking back at this experience, I think that in any case not using the Bombardier and restricting sampling to the deep waters very close to the camp was likely the best plan.  Getting the Bombardier’s engine to start in the extreme cold would have been difficult as well as the problem of taking samples in the extreme cold and keeping them from freezing; a minimum number and closeness to camp are always best.

Research on Lake Peters and Lake Schrader

I used Peters and Schrader data from summer 1958 and 1959 for an M.S. thesis at U.C. Berkeley and additional data from summer 1959 plus a year of data beginning in 1960 for my PhD from Indiana University.  Data included climate and lake data on water flow through the lakes, temperature, ice extent, light beneath the ice cover, oxygen concentration, algal biomass, and algal photosynthesis (primary productivity).

The wholly new measurement in my research was the yearly primary production in the plankton of an Arctic lake as measured by a new and very sensitive method, the uptake of radioactive carbon.  To calculate this and understand the controls, it was important to measure the actual amount of light penetrating the snow and ice cover.  To do this, I had to prepare early in the Fall.  I went out to the middle of ice-free Lake Peters and anchored two buoys 100 ft apart. One buoy had a pulley attached.   Then I tied a long rope to one buoy, ran the rope over to the other buoy, passed it through the pulley, and tied the end of the rope back to the first buoy.  Several times over the winter and spring, I excavated a large hole in the ice (Fig. 4.6) at one buoy and attached a light meter in a wooden frame that floated up against the bottom of the ice sheet.  I then used the below-ice rope to pull the meter back and forth beneath the ice sheet from one buoy to the other buoy to measure the light passing through the ice sheet at different snow depths and ice thicknesses (Fig. 4.9).  I found that the ice cover by itself was amazingly transparent – one meter of lake ice transmitted sunlight better than one meter of lake water.  There were no air bubbles at all in the ice.  I recall looking down through the ice once when there was no snow and the light meter was under more than 2 meters of ice.  I could see the small screws in the top of the light meter and even tell the orientation of the old-fashioned screws.   A little surface snow made a tremendous difference in how much light passes through the ice and reaches the water.  On May 22, 1961, only 1% of surface light passed through 140 cm of ice and 25 cm of snow whereas eight days later, 32% of surface light passed through 133 cm of ice and 0 cm of snow.  By June 14, there was still 94 cm of ice, no snow, and 43% of surface light entered the under-ice water.

The two lakes are quite different because Lake Peters directly receives water draining Mt. Chamberlin glaciers and so the lake becomes very turbid during the summer.  This change happened quickly.  As seen in Fig. 4.9, at sampling time # I in early June the glacially turbid water had not started to flow.  During the next three samplings (II, III, IV), the turbid water was flowing into the lake and filling up the lake basin from the bottom.  By August (V), the whole lake had become turbid (Hobbie 1962).  In contrast, Lake Schrader received water mostly from Lake Peters (Fig. 4.9), but much of the turbid material had been sedimented out and the volume of flow was small compared with the total volume of Lake Schrader.  Thus, Lake Schrader was much clearer than Lake Peters.

This difference (Fig. 4.10 versus 4.11) meant that Lake Schrader had a 14C-measured primary productivity that was about 10 times higher than Lake Peters (Hobbie 1964).  Because of this transparency of the ice and because of the low thickness of the snow cover during the spring, the total photosynthesis of the Lake Schrader algae floating in the upper lake beneath the ice cover was 50% of the yearly photosynthesis (algal growth).   In the exceptional year of 1959, the ice cover lasted nearly one month longer than in 1961 (until 26 July versus 28 June) and 83% of the annual primary production occurred beneath the ice cover.

Wolves, Wolverines, Grizzly Bears, and Dall Sheep.

One dark winter night, a wolf pack visited our camp.  In the morning we saw wolf tracks throughout our camp coming from a hillock several hundred meters away.  Perhaps the pack had been there for a whole day or longer – without the tracks, we would not have been aware of the pack’s close inspection. The pack certainly would have been interested in the close proximity of Dall sheep, which were seen all winter on the mountain heights above the Lake Peters camp.  These sheep occasionally moved down to the lake level to graze but only for a few hours.  Young sheep were born in late May or early June and the young with their mothers were visible virtually all the time from our camp (Fig. 4.12).  Males were rarely seen.

The only other mammal we saw frequently during the winter was an ermine, a small weasel with a completely white winter coat except for the black-tipped tail. This handsome carnivore came frequently into our front-door freezer room and would get within 2 or 3 feet of us while feeding on scraps of food.

From spring through the summer, arctic ground squirrels lived next to the camp (Fig. 4.13) on the alluvial fan. This champion hibernator (up to 8 months, the longest of any mammal) has been studied for potential insights into how to stabilize injured soldiers until advanced medical care is available. Their body temperature reaches -2°C during the winter, the lowest of any mammal, yet they must warm up several times over the winter so that they can get the sleep that even hibernators need.

An infrequent visitor was the wolverine, who visited the camp every two weeks or so but never came closer to us than a hundred feet.  I did see another wolverine but far away.  This occurred in early spring of 1961.  I was at camp and watching via a telescope while a white gyrfalcon contour-cruised along the upper reaches of a snow-covered slope about a mile away, presumably hunting for ptarmigan.  Suddenly, in my view were both the gyrfalcon in the air and a wolverine on the ground.  I then watched while the wolverine tobogganed down a long mountain slope with only its head showing above the snow.  It was as if he was swimming.

Grizzly bears live on the North Slope but hibernate for many months.  One morning in late August 1961, we had a fine view of a mother and cub as they walked calmly past camp.  People stayed close to camp except for a 67-year-old visiting Swedish botanist, Eric Hultén (Fig. 4.14), who rushed out to take a picture from as close as he could get to them.  He then assured us all that it was safe because he knew all about bear behavior from the years he spent in the wilderness of Kamchatka in eastern Siberia (1920-1922).  He also gave Olivann good advice about bears: “Never try to get between a mother bear and her cub.”  Eric’s definitive book on Alaskan plants has guided countless taxonomists and ecologists since its publication (Hultén 1968).  He also proposed that the area of the Bering Strait, including the land exposed between North America and Asia because of the low sea levels, was an important refuge for plants and animals during the Ice Age, and coined the word Beringia for this region.  Several dozen plant species have been named in his honor.

Over the four years of my time near Lake Peters and Lake Schrader, grizzly bears were seen many times; they have never been aggressive towards nor even very inquisitive about people.   The sole unfortunate interaction was in late May or early June of 1958 about a week before I first came to this site.  A U.S. Air National Guard C-123 cargo plane landed on the Lake Schrader ice sheet; there was already a moat between the ice sheet and the shore as incoming streams had raised the water level and the exit river had not begun to flow.  The crew members saw a grizzly bear walking along the shore and one of them shot and killed the bear.  There was no good reason for this.  This was the only time in the four years of research at Lakes Peters and Schrader that a bear was killed.  This casual killing illustrated the different attitudes towards wildlife of some of the military and of the scientific teams of the time.  I later sent the skull to the vertebrate collection at the University of California at Berkeley.  One interesting further sidelight was the interaction between grizzly bears and the tens of thousands of Alaskan workers building the Pipeline in the 1970s; the Pipeline Company absolutely prohibited them from bringing any type of guns to the field yet neither workers or bears were injured or killed in the two years of construction.  In fact, the bears were attracted to the camps by the waste food they were sometimes given.  This attraction did cause problems when the pipeline construction camps closed. The grizzly bears did come into the TFS quite a lot – at least for the first 5-6 years after the construction camps closed.

Bears can be particularly alarming during the mating season, when males are searching for females while females are still traveling with their cubs. In July 1969, Jaap Kalff of McGill University and I were sampling Shublik Springs on the Canning River for several weeks, 26 miles west of Lake Peters. The spring flows at the same volume and temperature (~5.5°C) year-round and its water was last exposed to the atmosphere 1,200 years ago.  We were walking on a hillside near the spring and traversing a field of tussocks – which are the curse of any human travel because of their uneven footing.  The action began when we saw a mother bear with two yearling cubs moving slowly up a hill about ½ mile away (Fig. 4.15).  Next, we noticed a fast-running bear moving up towards the mother and cubs from the valley bottom.  Because it was the bears’ mating season, we assumed it was a male bear.   After a short while, yet another bear came into view who caught up with the male bear and a fight began – we assume these were both males.  Unfortunately, the fight occurred just slightly over the edge of the hill so we could see them only when they reared upright and clawed at one another.  Soon, a single male bear headed somewhat slowly uphill towards the mother and cubs while the other male bear remained behind licking his paws.  When the uphill bear came within a hundred yards of the mother and cubs, yet another bear came running up the hill (was it the same already defeated bear or a completely new bear?) before turning around and being chased downhill, towards us, by the first bear. At first, we were not worried as they were at least a half mile away and there were several stream valleys for the bears to cross.  But they moved fast (Fig. 4.16) and always seemed to head directly at us.  I had a rifle with me but mentioned to Jaap that it was too bad that I had never actually test-fired that gun.  Jaap was in charge of the camera and replied that the bears were close enough that he had refocus the camera lens – his implication being that perhaps I should figure out quickly what our options were!  Finally, from about 100 feet away the lead bear saw us, stopped, and stood upright to look at us (Fig. 4.17)—and he had a beautiful coat.  Then he started to run away followed by the second bear.  They ran up a nearby hill and startled a small caribou herd that then ran before them.  The herd split and half went up the skyline and half went down the skyline and the bears ran up the middle – what a sight!  Oh yes, we did notice how fast the bears were able to run over tussocks.

Golden Eagles, Shrikes, and Giant Lake Trout

On May 2, 1961 I observed two golden eagles copulating and building a nest near an old nest on a cliff face several hundred meters from the Lake Peters camp.  This was the farthest north nesting activity has ever been reported for this species.  Tom Cade, an ornithologist at Cornell University, and I described this in a publication (Hobbie and Cade 1962) but no young were ever seen. Tom Cade later founded the Peregrine Fund, a raptor conservation organization that was instrumental in restoring populations of the endangered peregrine falcon, as well as other birds of prey.

Cade was at Lake Peters to study the northern shrikes which nested in willow shrubs on several of the alluvial fans along the Lake Peters shore.  I weighed the young shrikes after Tom left (Fig. 4.18).  He carried one of the young back to Cornell—in a small box—and went into the Men’s Room at each airport to feed the young bird with pieces of wild meat.  The bird was very noisy when being fed so Tom pasted up a sign at the entrance – that said SHRIKES.  Somebody entering misread the sign and agreed that shriek was a good name for that bird.

The Lake Trout (Fig. 4.19) is at the top of the aquatic food chain in these lakes.  In the springtime, I observed these trout in very shallow water between the lakes and saw them grabbing voles who chose to swim across a shallow inlet.   But the trout’s usual prey is certainly the full-sized arctic char (Fig. 4.20) that was the only animal I observed in the guts of the lake trout that I trapped in gill nets.  The arctic grayling (Fig. 4.21) were also found in the lakes but are mainly present in streams and must move to the lakes to overwinter when the streams completely freeze.  Unfortunately, the lake trout were prize catches for sportsmen who happened to visit these lakes.  Large lake trout, like those taken by a military party visiting at the end of the summer (Fig. 4.22) are probably at least 50 years old.

Olivann Returns Home, Replaced by Chuck Hobbie

Because our first child was due in August, Olivann visited the Barrow hospital in March.  All was well and she stayed at Lake Peters until she flew home in early June on the last plane that took off from the melting ice sheet.  After 9 months on the frozen tundra, she regretted having to miss the brief Arctic summer. John’s 16-year-old brother, Chuck, flew in several days earlier but had a somewhat exciting introduction to weather problems.   When the incoming plane reached the valley, it was covered with fog and they could not land.  There was no other option than to fly up to Kaktovik (then Barter Island) on the coast, the nearest settlement with an airport (it also was a DEW Line site – Distant Early Warming radar sites aimed at Russian airplanes).  The pilot, Lloyd Zimmerman (Zim), radioed to Barter Island but was refused permission to land.  He landed there anyway, having no other choice – the next airport was more than a hundred miles away.  The illegal landing upset the local military police but after some heated discussion, Zim and Chuck were allowed to refuel, eat dinner, and finally landed back at Lake Peters at 9 in the evening.  Chuck helped John with sampling and took over the weather measurements until they both left at the end of August (Fig. 4.22).  In addition, he earned some cash from a Princeton University project by measuring the daily hours of activity of the Arctic ground squirrels (Fig. 4.12).  These squirrels hibernate for most of the winter and found the gravel and sand at the end of the alluvial fans ideal for their burrows.  Chuck took several short flights with Pilot Zimmerman and flew around the summits of Mt. Chamberlln and other major Brooks Range peaks.  The first flight, on floats, he called “the ride of his life”.

5.       The IBP Tundra Biome at Barrow: 1970-1974

Figures IBP

Overview of The Tundra Biome within IBP

As a major part of the U.S. participation in the International Biological Program (IBP), NSF funded in 1970-1974 five large U.S. biome studies (Grasslands, Deciduous Forest, Coniferous Forest, Desert, Tundra).  These biome studies were each a major project of the U.S ecological community.  Moreover, the IBP marked a dramatic increase in the scale of funding for ecosystem ecology worldwide (Wikipedia, International Biological Program).   While each biome project represented an important ecological region of the U.S., the methods and specific questions addressed were different for each biome.

Naval Arctic Research Laboratory (NARL); New Laboratories and Living Quarters

The terrestrial and freshwater field work of the Tundra Biome project was carried out at Barrow with some special projects also based at the new Prudhoe Bay petroleum development region (320 km or 200 miles to the east) (Fig. 5.1).  At Barrow, the biome projects used the newly constructed NARL facility (Shaver 1996).  This modern building replaced many Quonset huts and was the first large building at Barrow that was raised up on stilts to prevent thawing of the underlying permafrost.  Pictures of the building (Fig. 5.2), taken recently, show an outdoor staircase of 15 steps which translates to a height of 267 cm (8 or 9 feet).   The building was shaped like a giant letter “H” with one leg a string of laboratories, each with running water, sinks, lab hoods, tables, and desks.  The other leg was a string of double occupancy sleeping rooms.  The middle of the H was a large recreation and lounge room along with the director’s offices and rest rooms.  The food facilities were across the street and the food was extraordinarily good.  One Swedish scientist, Stefan Holmgren, said that there was so much beef on each plate of food that he went into training before getting to Barrow so that he could eat it all.

At Barrow, hundreds of scientists, students, and support personnel were involved under the overall leadership of Jerry Brown with Larry Tieszen heading up terrestrial studies and John Hobbie heading up aquatic studies.  Each of these leaders edited a large book on the results—just to indicate the number of scientists taking part, the Brown et al. (1980) book had 32 authors, the Tieszen (1978) book had 44 authors, while the Hobbie (1980) book had 19 authors.

Another good feature of the Tundra Biome was that the oil industry contributed funds for terrestrial ecological research at Prudhoe Bay.  For this, Donald Walker, a graduate student at the University of Colorado, set up 89 study plots in the four types of habitat and found 43 types of plant community for his PhD research.   Some of these oil company funds were used to pay for the costs for scientists and families to spend the summer off 1974 at a University of Colorado research station to begin to write two books.  Incidentally, some NSF officials objected to this use of oil company funds and the Tundra leaders were told it was not allowed.  Happily, this attempt fizzled in the upper regions of NSF.

Tundra Biome Publication Success

Numerous scientists from many institutions came together to carry out the research at Barrow over three summers.   The spread in home institution locations makes it difficult to write the multi-authored papers and books that were the goals of these large projects.   Therefore, to accomplish the publications a special plan was set up.   Field work would end a year before the funding ended.  Therefore, the field measurements took place in the summers of 1971, 1972, and 1973; the summer of 1974 was spent in synthesizing and writing.   All project scientists spent much of the summer at the University of Colorado Mountain Research Station, near Boulder.  In retrospect, this decision to encourage face-to-face discussions, arguments, and collaborative writing in an isolated setting provided a successful if unintentional template for how to conduct the ‘business’ of science at the Toolik Arctic Research Station beginning in 1975. The papers and books produced during the Tundra Biome helped win funding in the 1987 competition by the NSF for new long-term ecological research (LTER) projects.  The Toolik-based project won, in part because the scientists involved had already proven that they could work together and to synthesize data in the Arctic.

Yet one more good feature of the Tundra Biome came from the U.S. Army’s Cold Regions Research and Engineering Laboratory (CRREL), where Jerry Brown worked.  Their staff helped in many needed and unexpected ways to prepare the illustrations and help edit the two Tundra books published in 1980.  Such knowledgeable and helpful support rarely occurs in universities.

Research Themes and Sites: Terrestrial and Aquatic

As described by Hobbie (2014), the overall themes were (1) to develop a predictive understanding of the arctic ecosystem, (2) to obtain a database for modeling and comparison, and (3) to use environmental knowledge for problems of degradation, maintenance, and restoration of ecosystems.  One of the ways the entire project was integrated was the whole-system goal of understanding carbon, nitrogen, and phosphorus cycling.  To accomplish this, all the major ecosystem components in the tundra and ponds such as primary producers, decomposers, herbivores, predators, climate and microclimate, and sediments and soils, were measured.

The research site was inland from the ocean and 5 km southeast from NARL on an ancient bed of a large shallow lake (Fig. 5.3, Fig. 5.4).  Most important, there was a good road out to the site.  For the aquatic study, investigators focused on three small ponds (Fig. 5.5). In the terrestrial study, the focus site was the predominant wet sedge tundra.

Terrestrial research was carried out on the Barrow peninsula, the northernmost point in Alaska.  The research region is described in Brown et al. (1980) as a littoral region or one lying immediately next to a sea or a lake.  At Barrow, the sun is above the horizon continuously from 10 May to 2 August.  Air temperature is below freezing nine months of the year and there is continuous permafrost.  An insulating snow cover, 20 to 40 cm thick, forms during the winter and begins to thaw in early June.  Based on 30 years of data, there are 91 days each year when the average temperature is above 0oC.  Fog and clouds persist through the summer when the average humidity is usually above 80%.  The coastal tundra has low species diversity, dominance of grasses, and sedges, a rarity of tussock tundra, and the absence of erect shrubs.

Aquatic studies were carried out in ponds close to the terrestrial site.  This was the first time that a large number of aquatic scientists had ever worked closely together.  This made possible to construct carbon-flow diagrams that brought together many different parts of the aquatic ecosystem.  It was also the first time that aquatic research used modeling as a tool.  Many chemical analytical instruments were brought to Barrow so rate measurements could be made during the field season.  In this research all measurements were made at Barrow so the latest type of lab instruments were imported.  For example, there was an automatic 14C (radiocarbon) counter to measure planktonic primary productivity as well as inverted fluorescent microscopes to count the numbers and biomass of bacteria.

Papers were written with many authors, graduate students wrote theses, and scientists learned how to work together.  The IBP project brought a new level of sophistication and integration to Arctic research and was an important precursor for the research at Toolik Lake; for many scientists, their IBP training shaped their views of how to integrate future Arctic research.

Location, Views, Ecology of Tundra Ponds

As noted, the ponds studied were on an ancient lakebed (Fig. 5.3, 5.4).  The lakebeds are filled with patterned ground where raised shorelines enclosed shallow ponds.  Three of these small ponds (Fig. 5.5) have been studied in detail; this photo shows the power lines extending from the NARL, the small field laboratory building, the wood plank walkways, and the cable-car that allowed scientists to sample the water and sediment without disturbing the bottom of the pond (Fig. 5.6).  The shoreline of the pond holds plastic boxes, some with heated water, containing small experiments.

The most important control over the biota living in the water and sediment of these ponds (Fig. 5.7) is that the ponds are completely frozen, the sediment, the water, and the ice, from mid-September until early June.  For this reason, there are no fish in the ponds.  The large Daphnia survive as overwintering embryos and the copepods, another planktonic animal, survive freezing in a pre-adult growth stage.  The soft bottom (benthic) sediments contain a few worms, a snail species, and many insect species that survive as very abundant larvae for up to seven years.

The most important limiting factor for the photosynthesis of the phytoplankton in these ponds is the phosphorous concentration.  This was discovered by Jaap Kalff in his PhD thesis at Indiana University (Kalff 1971) and confirmed in the IBP research by whole-pond addition (Fig. 5.8).  The details of the transfer of phosphorus within the plankton and benthic food web are shown in Fig. 5.9 (Prentki et al. 1980), many of the measurements were made using the radioisotope 32P.  It is remarkable that the nanoplanktonic algae, only 2 to 20 microns in size, take up most of the dissolved phosphorus every day but that an equivalent amount is excreted every day from the zooplankton.

The remarkably detailed study of the flux of phosphorus through the planktonic and benthic food webs of a tundra pond by R. Prentki (Fig. 5.9) was replicated for carbon and nitrogen fluxes by V. Alexander, J. Kelley, P. Coyne, M. Miller, and R. Barsdate (Chapter 4 in Hobbie (1980).  The inorganic nitrogen was abundant enough that the turnover times were 30-100 days; in comparison, the phosphorus turnover time was only 1 day

Location, Methods, Results of Terrestrial Tundra Studies

The research tundra sites are near the series of white huts shown in Fig. 5.4).   The dominant grasses covering the tundra sites (Fig. 5.10) were Dupontia fisheri, Eriophorum angustifolium, and Carex aquatilus (Carex is also shown in Fig. 5.7 as it grows into the shallow edge of ponds).  Roots of Dupontia are concentrated in the top 5 cm of soil where phosphate and potassium are abundant and temperature and aerobic conditions are most favorable for absorption.  Eriophorum has thin annual roots that grow downward following the seasonal thaw – phosphorus is likely highly available at the freeze/thaw interface – and the entire root system must be replaced every year.  Carex produces long-lived, thick primary roots, has more tissue in roots than the other species with the result that Carex is most successful in nutrient-poor situations (Shaver and Billings 1975).  It should be noted that the research reported in this paragraph was the PhD research of Gus Shaver who later wrote many papers about the Arctic, later became the principal investigator of the Arctic LTER, and later was organizer of the terrestrial chapter in Alaska’s Changing Arctic (Shaver et al. 2014).

The amount of carbon in tundra (Chapin et al. 1980) contrasts with most other ecosystems in the world in that the bulk of its carbon is in soil rather than in live biomass (Table 5.1).  At Barrow over 96% of the organic carbon is bound in dead organic matter and 1.7% or less in living organisms.  In contrast, 50 to 75% of the organic carbon in forests and 10% of the carbon in grasslands is in living organisms.   The mid-latitude grasslands also have most of their carbon in dead organic matter.  But in grasslands, roots penetrate 1 to 2 m so that carbon from dead roots and associated microorganisms are distributed throughout the soil.  In the tundra, in contrast, there is a distinct surface horizon 10 to 20 cm thick, in which the percent of organic matters is 90 to 96%.  Such high concentrations of organic matter are associated with low pH and reduced nutrient availability.

As shown in Fig. 5.11, lemmings have amazing life cycles near Barrow.  The brown lemming (Lemmus trimucronatus) is the dominant (and sole) herbivore in the Barrow coastal tundra (Batzli et al. 1980).   Their density may reach 225 ha-1 during a late-winter peak in population but this level is unsustainable and the density soon falls to 0.02 ha-1.  Peak populations may occur every three to six summers.   In a pre-high winter, lemmings reproduce in nests made of dead grass and sedges at the base of the snowpack.  The population grows rapidly, peaks in late spring, and ceases reproduction in May when all suitable forage has been consumed.  These events are revealed during snowmelt when massive clippings of grasses and disruption of moss and lichen carpets are seen.  At this time, lemmings scurry everywhere and predators attack.  These are pomarine jaegers (Stercorarius pomarinus), snowy owls (Nyctea scandiaca), and least weasels (Mustela nivalis).  One reasonable theory about these events is that there just is insufficient available energy for the lemmings in late spring.  Grasses and sedges do become available during the summer but the failure of the lemmings to respond may be the continuing effects of earlier undernutrition.

There was year-round power available at the terrestrial research plots; one questioner asked about the effect of winter warming on the soil.  When a plot was kept warm overwinter (Fig. 5.12), the experimental heating proved to have a series of consequences that led, in the end, to an anaerobic snow-cave that killed the plants and eventually caused a small pond to form.

6.       Pipeline Road and Alyeska Toolik Construction Camp:  History and Impact on Regional Ecology

Figures - Pipeline Road

History of Oil Discovery, Road Building, Pipeline Construction

In 1968, two oil companies announced the success of a well at Prudhoe Bay (Fig. 2.5); oil was discovered at a depth of 9,000 feet.  British Petroleum wasted no time and began planning for an 800-mile pipeline to Valdez on the Pacific Ocean; the eventual route and the pump stations are shown in Fig. 6.1.  From November 1968 until March 1969 the state constructed a 400-mile winter road called the Hickel Highway (after governor at that time Wally Hickel) from Livengood, 70 miles south of the Yukon River, to Sagwon, 58 miles south of the Arctic Ocean and at the southern limit of the coastal plain (mile 353 of the Dalton Highway).  This was an ill-planned road that used bulldozers to scrape away the protective vegetation and topsoil and exposed the permafrost to summer heat and quick erosion.  It was soon abandoned but the scars of the roadway are still visible in a few places and illustrate the long-term consequences of destroying the vegetation and uppermost soil layers (Fig. 6.2).  Next, a summer-only road, the Haul Road, used the present path through the Brooks Range and was completed in 1970.   A year-round road was still needed.

In June 1969, the Trans-Alaska Pipeline System (TAPS), a joint project of ARCO, British Petroleum, and Humble Oil, applied for permission to build an 800-mile pipeline. The pipe was to be 48-inches in diameter (122 cm) and wholly subterranean.  In response the Interior Department sent experts to examine the route and the building plan.  One expert was Max Brewer, a geologist and director of the NARL at Barrow.  He reported that the plan was not feasible because they had ignored the permafrost.  He said, “A heated pipe would melt the underlying permafrost, causing the pipeline to fail as its support turned to mud.”

Some native groups supported the pipeline, but several Alaskan native groups and conservation groups soon organized suits against the pipeline plans and in this way held up the start date for actual pipeline construction.  However, geopolitics, specifically the Yom Kippur War of October 1973, resulted in the Organization of Arab Petroleum Exporting Countries announcing an oil embargo against the U.S. because of its support of Israel during the Yom Kippur War against a coalition of Arab States.  Because the U.S. imported 35% of its oil at the time, the embargo had a major effect.  In November 1973 Congress settled the arguments and passed both the Alaska Native Land Settlement act and the Trans-Alaska Pipeline Authorization Act.  In April of 1974, construction actually began for the year-round Haul Road and the road was completed in September 1974 (see Fig. 2.5 and Fig. 6.1 for location of Toolik Lake on the Haul Road and Fig. 6.3 for a view of the action on the date of road construction).  The Haul Road cost $125 million.  In March 1975, the pipeline construction began and ended in 1977; it cost $8 billion.

Crossing the Yukon River by Hoverbarge

Until 1975, the only way to cross the Yukon River was by a riverboat in the summer or by driving across the winter ice-cover.  When the Haul Road and Oil Pipeline were being planned, a bridge was decided upon.  However, when serious road traffic began in 1975 the bridge was still unfinished – it was finally opened in October 1975 (Fig. 6.4).

Beginning in April 1975 cars and trucks were transported across the ice and water of the river by a hoverbarge (Fig. 6.5).  Note – there is a 14 minute film on the 1975 hoverbarge operation for crossing the Yukon River ( is external) see section on The Yukon Princesses).  There were two barges, both fastened to the same cable, that went back and forth across the river and passed in midstream (Fig. 6.5).  Each trip took 15-20 minutes.  Each barge could carry a maximum of four trucks, each truck could carry three 80-foot sections of the 48-inch diameter pipeline.  A large powerful fan on each barge pumped high volumes of air below the barge–the air was mainly contained in plastic skirts that barely touched the water—and the resulting air cushion lifted the barge structure above the water or above the ice. This hoverbarge operation ran only for the 6 months it took to complete the bridge across the Yukon River but successfully coped with winter ice, breakup ice flows, and the high water of spring breakup.

Driving on the Dalton Highway

Problems included flying rocks, cracked windshields, and tremendous clouds of dust raised by frequent trucks.  Some days it was best to stop along the side of the road whenever a truck passed until the blinding dust subsided.  In later years more and more of the highway was paved and conditions improved.   See http:/ road/htm/img_abels_02.htm.

Alyeska Toolik Pipeline Camp

Along the pipeline there were 12 pump stations (Fig. 6.1) and 20 construction camps, which included 16,500 beds.  A total of 28,072 people were employed during the peak construction period of Fall 1975, and high turnover meant that 70,000 people had worked on the pipeline by its completion.  The Toolik camp, which supported 400 persons, was constructed in 1970 and closed in the fall of 1976.  It was set up by truck transport along a winter road over frozen tundra, the Hickel Highway, in expectation of the imminent start of road construction.   In the early days, large transport planes also landed on Toolik Lake to bring in construction materials during the winter.

The Alyeska Construction Camp at Toolik Lake was about a mile off the Haul Road and quite near Toolik Lake (Fig. 6.6).  The original sign for this Construction Camp could still be read in the early 1980s (Fig. 6.7); at the Camp there were a large number of buildings, including living quarters, a dining hall, repair shops, and sewage treatment facilities (Fig. 6.6A).  There was a freshwater intake down at the lake built at the end of a massive steel pier extending out into the lake and a very long pipe that conducted the water up to the camp (Fig. 6.6B).  There was even an airstrip that was no longer used in 1975.  A peninsula at the south end of the lake was likely the site where naturally occurring piles of sand and gravel had been mined for some years – in the aerial view these are the white places on the peninsula and at several sites just to the south.  This area also became the storage site for disused equipment and construction materials.  Later, in the early 1980s, it became the location of the present Toolik Field Station.

The official permission to build the pipeline was delayed until late 1973; for this reason, the camp was unoccupied for several years.  The camp reopened during the winter of 1973-1974 and, amazingly, the gravel road (Haul Road, later Dalton Highway) was completed in fall 1974.  One unique feature: buried alongside the road is a 20-25 cm diameter natural gas pipeline running from the Prudhoe Bay oil field to fuel the two pump stations away from Prudhoe Bay but still on the North Slope.  Pump Station 4 is some 16 miles south of the Toolik camp and Pump Station 2 is north of the camp, close to pipeline mile 350.  The oil pipeline was completed in 1977 (Fig. 6.8) and seven of the construction camps along the road were closed the previous November (including the one at Toolik Lake), and six more closed before the 1977 construction season started.  All 20 camps went up for sale and all remaining camp buildings and even waste dumps were removed.  Roscow (1977) states that a number of camp buildings were sold to the University of Alaska for use as an Arctic research camp (Toolik Field Station).

Life at a pipeline camp was quite good, especially in the first year of operation.  At that time, the food service was operating on a cost-plus basis and the meals were fabulous.  There was often steak for lunch and such foods as lobster and crab salad for dinner.  The cost of meals led to a rethinking of menus so that the food during the second year was more normal but still very good.  The road allowed large, refrigerated trucks to deliver food to the camps several times a week.  The living quarters were mostly multi-room trailers linked by insulated hallways.  There were two beds in a 10 x 12 foot room and the housing trailers also included large restrooms and showers.  Each construction camp collected water from local lakes and streams and a water treatment plant purified the water for drinking.  Solid sewage wastes were sent up to a large treatment plant at Prudhoe Bay.  Liquid wastes underwent tertiary treatment and were disposed of locally.

Although alcohol was banned, enough came in illegally that parties and nightly gambling in card games were popular.

The ratio of men to women workers was about 10:1. These few women received constant attention and greetings.  Sometimes there was harassment, but it was fairly rare. One unusual check on such behavior, not available to urban workers, was recounted by Seth Beaudreault, in which a woman pipeline worker was being harassed by a male worker.  Once he left his truck unattended and she punished him by leaving a sandwich inside the cab.  When he returned, there was a bear inside enjoying the sandwich!

7.       Move to Toolik Lake 1975; Project RATE, Man and the Biosphere; Toolik up to 1983

Figure - Move to Toolik

Ecological Research Continues Away from Coast

The IBP Project ended in 1974.  However, funding for ecological research in northern Alaska remained in the NSF Arctic budget and so Project RATE (Research on Arctic Tundra Environments) was funded by the NSF in 1975.  This project was a part of the Man and Biosphere Program (MAB), Project 6, Impact of Human Activities on Mountain and Tundra EcosystemsTerrestrial studies were begun at Atqasuk on the Meade River (Batzli and Brown 1976) which is 95 km (57 miles) south of Barrow.   Aquatic studies continued at Barrow, but there was also an effort on the North Slope to find a new research lake deeper than a few meters.  Hobbie says “I made an early June flying trip to the Meade River site where I hiked out to a nearby lake, laboriously drilled through a lake ice-sheet that was 1.5 m thick, and then found only 15 cm (6 inches) of water underneath!”.  After several other trips turned up only shallow lakes on the coastal plain, the aquatic scientists decided to look in the foothill and mountain regions along the newly completed (fall 1974) gravel road (now Dalton Highway) that ran alongside the partially constructed Alyeska Pipeline (completed 1976).  This road, the only road on the North Slope, allowed access to the coastal plain, foothills, and mountains of the North Slope of Alaska.  The Dalton Highway starts 84 miles north of Fairbanks and stretches north for 414 miles to within a few miles of Prudhoe Bay on the Arctic Ocean.   Details of the region are reported in the Dalton Highway guidebook (Brown and Kreig 1983) and the Dalton Highway Wikipedia description.

During the extraordinarily large IBP research project at Barrow, a few scientists carried out terrestrial research at Prudhoe Bay (e.g., D. Walker), the site of the oil discovery and of continued exploration.  These scientists were associated with the IBP project, but the oil companies contributed funds.  Therefore, it was easy for the RATE aquatic scientists to obtain permission to travel on the Dalton Highway and rent a truck from the private companies working at Prudhoe.

Choosing the Toolik Site

In early June 1975, six RATE scientists, Jerry Brown, John Hobbie, Philip Miller, Michael Miller, Vera Alexander, and Pat Webber (Fig. 7.1), drove south along the Dalton Highway.  They were looking for a deep lake in the foothills or mountains, a lake with fish, and a lake accessible from the highway.  John, Mike, and Vera were a part of the IBP Freshwater Project.  Later that summer, a group of terrestrial RATE scientists conducted a more detailed reconnaissance from Prudhoe Bay to the continental divide in the Brooks Range.   Hobbie recalls that the initial exploration group knew nothing about the various possible locations along the Dalton Highway as the road construction had just been completed the previous Fall, and there were no available maps or descriptions of the landscape of the road, which was, of course, privately built and controlled.  Much to our surprise, we found only one place where a deep lake could be studied, and a camp established and maintained.

Mike Miller recalls that “the group flew in to the Deadhorse Airport on June 8th or 9th when the coastal tundra was still brown.  When we rented a vehicle and drove south, the tundra began to green.  Finally, at Toolik the surrounding tundra was a beautiful green and flowered.”  He quotes Hobbie as saying “if the lake is greater than 10 meters deep, then this is our new home”.  The lake was still ice covered except for a ring of open water next to the shore but Hobbie took a small rubber raft, crossed the moat at the lake’s edge, and cautiously walked out towards the middle.  He did find more than 10 m depth.  Miller recalls that this expedition was lucky in that there are both deep basins and shallow ridges in the lake and the team missed hitting a ridge in its first measurements.  The only other lake that might have been suitable was Galbraith Lake some 10 miles farther south; however, because a quite large river flows through Galbraith Lake, the depth of the lake and its clarity change rapidly during the spring flood and during periods of heavy rain.  Toolik Lake, in contrast, has only small streams flowing into it so that the causes of changes within the lake can be followed and studied.

Toolik Lake Description, Alyeska Construction Camp

Toolik Lake lies in the foothills of the Brooks Range some 120 miles south of Prudhoe Bay.  It has deep water (26 m), 5 species of fish, and accessibility by road.   This lake-side site (Fig. 6.6) was earlier chosen for the Alyeska Toolik Construction Camp built in 1970 and used for road and pipeline work from 1973 to 1976.   In the early days, construction materials were flown to the lake as large airplanes could land on the winter ice.  Year-round the lake provided freshwater for the camp; the lake and Alyeska Camp are located on a side road ½ mile from the Dalton Highway so are away from traffic and road dust.  This camp held up to 400 people and continued operation until fall 1976.  Eventually all the buildings and material were removed from the site as a part of cleanup of all pipeline construction.

Characteristics of the Toolik Region

The three glacial advances produced soils with dramatically different lengths of time since glaciation; these differences produced soils with different pH’s and slightly different types of vegetation.  There is no pollution or N deposition, an average of 300 mm of precipitation and an average temperature of -8oC.

“The dominant plants of the foothills are the sedges and grasses of tussock tundra, a vegetation type that covers some 80% of arctic Alaska. Low shrubs, including birches and willows, grow between the tussocks and abundantly along the streams.” Scientific advantages of the location of Toolik Field Station:  1). Headwaters of several rivers, large number of lakes of various sizes, all close,  2). Land-surfaces from three different glacial ages near Toolik.  3). Road access to a number of terrestrial ecosystems along the north-south route of the Dalton Highway.

See is external)) for pictures (some from Mike Abels) of Toolik Research Station.  In the early days, the entire Dalton Highway was only open to commercial traffic (and Toolik trucks). The state took over the road in 1979 and in 1994 it was finally opened to all traffic.

Early Days at TFS

On the 1st of July 1975, the first group of scientists began measurements of Toolik Lake.  To get to Toolik from Barrow, they were flown by the NARL Twin Otter from Pt. Barrow to Prudhoe Bay where they rented a truck to drive down to Toolik.  The team is seen leaving NARL (Fig. 7.2) with Mike Miller in the cab and John Hobbie, John O’Brien, Jim Haney, Sam Mosley, and grad student Carl Zimmerman in the truck.  They camped on the tundra next to the unused airstrip that begun at the edge of Toolik Lake (Fig. 6.7).   This was the place where the Alyeska Construction Camp had a small pumphouse to move lake water up to the Construction Camp and where the water-hose crossed the runway (Fig. 7.3).  The Camp had also constructed a very large steel pier so that the water intake was quite far out in the lake (in the background of Fig. 7.4); evidently the Pipeline Camp wanted to make sure there was adequate water depth for overwinter water pumping.

Miller recalls that “in 1975 we made eight flights from Barrow to Deadhorse Airport and drove down to Toolik; a small travel trailer for our use was towed to the Toolik site from Fairbanks and named “Vera”.  Unfortunately, we did leave food in the trailer and in-between our trips a grizzly bear tore into the ‘Vera’ trailer through the wheel-well.  The pipeline workers at the Toolik Construction Camp noticed the damage, picked up the trailer with an immense tractor, and took it up to their camp for repair.  So, on our return to Toolik, there was no trailer.  Eventually we went up to the camp and learned the story.  Soon a huge payload tractor appeared carrying the small trailer and replaced the trailer at the end of the airport runway.”  Miller notes that later “Steve Whalen and Jeff Cornwell, grad students at UAF (University of Alaska Fairbanks), had a volleyball game with Toolik Construction Camp macho men and beat them.  Then we had a dance with the men’s homemade beer.“  Claire Buchanan and Ben Cuker gave a jitterbug lesson, which was a thing of beauty, if you can imagine Claire going over his head and between his legs (Fig. 7.5).

The final hike at the summer’s end was over the Sagavanirktok River and up the ridge.  Dan Strome, Claire Buchanan, John O’Brien, and me crossed the river in the morning at low water all roped together carrying our boots and packs over our shoulders, hiked up the mountain, had a fresh grayling dinner, camped overnight, then returned the next afternoon only to find the river a foot deeper and a lot faster.  Getting back was no fun, but fortunately we all made it.”

One of the RATE scientists left at NARL was Mac Butler, a graduate student of Sam Mosley (N.C. State University).  He relates what happened at NARL this day in 1975 that illustrates the somewhat tense relationship between the scientists at NARL and the Inuit people living in Barrow (renamed Utqiagvik in 2016) some 5 miles to the south.  When the PIs and graduate students remaining at NARL went out to the pond research site on that 1 July 1975, they found that their oil spill experiment on a large, shallow pond had been trashed.  Five gallons of crude oil were emptied onto the tundra, mercuric chloride was spilled into the pond, floating emergence traps were sunk, and a raft used to tend the traps was slashed open.  An ornithologist on an early morning survey reported that 6-8 teenage boys had been there carrying a rifle and machete.  Luckily, that was the only trouble during that summer.

Toolik Field Station and Alyeska Camp Interactions

The new research camp was located at the north end of Toolik Lake, near the lake outlet and at the south end of an unused gravel airstrip.   During the summer, scientific groups from Barrow made eight short trips to Toolik.  Each time they brought tents, food, and scientific sampling gear.  Trucks were rented at Prudhoe Bay.  In June, a 16-foot travel trailer belonging to the Institute of Marine Science (IMS), University of Alaska Fairbanks (UAF), was placed at the north end of the lake and near the Alyeska Construction Camp (Fig. 7.6).

During the winter of 1975-1976, Alyeska Camp continued to be active and the entrance road to the Alyeska Camp was kept plowed.   But the pipeline was completed in September 1976 and Alyeska Camp immediately ceased activity in the fall of 1976 so after that date the road off the Dalton Highway was not plowed.  Instead, trucks from Fairbanks were met up at the Highway and snowmobiles and sled from TFS hauled people and supplies the next spring (Fig. 7.7).

The Institute of Arctic Biology employed Dave Witt as the logistics provider for the IBP project at Barrow.  This IAB support that he organized, was continued by NSF to serve the Toolik Field.  An incoming student, Mike Abels, was hired to help for the 1975 summer; he continued to work for UAF (Fig. 7.8) and later became Operation Manager for the TFS until his retirement in 2021.

A much larger TFS camp was assembled during the summer of 1976 which included a 10 x 50-foot trailer, a 20 x 25 food storage tent, and a mobile home for sleeping.  In 1977 another trailer was sent up.   These were all ATCO trailers bought by the University of Alaska during the closing of the pipeline camps at $2,000 each; the mobile home was used for research at Prudhoe and driven down to Toolik (Fig. 7.9).  These 10 x 50-foot trailers served as the cook shack and research space.  These, along with various tents, the small Vera trailer, and temporary plywood sheds made up the research camp (Fig. 7.10). ( is external)).  We also constructed a sauna – one window was the front windshield of a wrecked truck.

Mike Abels has recorded an interview for Project Jukebox of the University of Alaska ( is external)).  One early event occurred in 1976 when Mike and three others hauled a 10 x 50-foot long trailer the 375 miles from Fairbanks to Toolik.  They had two persons in a trailer-puller truck and two in a chase pickup-truck following behind.  Their speed was 10-15 mph, and they did not stop but took turns sleeping.  There were no maps for the road and no mile-markers so Mike, certainly, did not know where they were on the road and exactly where Toolik was.  As they passed over Atigun Pass, the steepest part of the trip, the tow-truck kept popping out of gear and the passenger (Mike, as it happened) had to press on the gear-shift lever with both feet to keep the gear in place.   At the base of Atigun Pass, they decided to stop overnight so all could sleep.  The next morning, they discovered they were only 22 miles from Toolik.

Interactions between the Alyeska camp and the Toolik Research Station were rare despite being less than a half-mile apart.   In the early years, one major problem for TFS was communication with Fairbanks.  Of course, the pipeline construction camps did have microwave communications but would not let TFS people routinely use it.   The only possibility was single sideband radio that was not reliable – it connected to a private company in Fairbanks which would make a phone connection to the UAF phones.  So, in the 1975 and 1976 summers, the scientists at the Toolik Research Station did occasionally use the telephone system of the pipeline camps to contact the support facility at UAF.  It sounds simple but in the 1970s the choice was short-wave radio or telephone by landline.  And to get on the phone from Toolik to Fairbanks took three or four connections to be made on the landline.  Another important task was to dispose of sewage from the TFS.  In 1976 the disposal was at the Alyeska Camp and it was organized by Torre Jorgenson, the TFS manager.

Other useful contacts included a very important use of the tire repair facilities at the Alyeska camp, and some socializing of the Research Station staff with the Alyeska employees.  There was one morning when the breakfast table featured a large note telling people to cook their own pancakes after mixing the contents of the two large bowls.

Interactions Among People: Cuker

Ben Cuker, a beginning graduate student (Fig. 7.11), reports: “In the 1970’s we lived in small tents scattered on a section of the tundra between the camp on the disused runway and the edge of the lake (Fig. 7.4).  To tease Cathy Pringle, another beginning graduate student, I often pretended I was a bear, growling and pressing on Cathy’s small pop tent as a means of wishing her a good morning.  One day I awoke to Howie Reisner blasting an airhorn while stepping backwards.  He had come to Cathy’s rescue, trying to scare off a juvenile grizzly bear that had pretended it was me – pressing on Cathy’s tent and growling!  Cathy told me later she actually thought it was me at first, and told the bear, “Go away Ben!”  That bear stuck around camp for a full day.  It appeared delighted to burst, one by one, Mike Miller’s plastic one- gallon Cubitainers of radioactive water floating in a small pond.  Eventually an emergency radio call brought in a helicopter with a state trooper with a big rifle.  A few shots scared off the bear for a time.  John Hobbie, who shared a nearby tent with assistant John Helfrich, remembers the same early-morning-bear incident but when Cathy saw the shaggy shadow on the tent walls and began to scream for some reason, he incorporated the screams into a dream he was having and did not wake at all.  After that incident, the camp got a shotgun to fend off future unwanted visitors.”

Ben Cuker says camp was perpetually noisy in those days.  “The backup alarms of the construction trucks constantly echoed across the tundra.  After the pipeline was completed in 1976, we replaced those sounds with our own noise pollution.  An internal combustion engine generator produced electricity for the cooking trailer and primitive laboratories.  We all loved the times when it would run out of fuel, providing just short bits of relief from the constant din.   In the age of the smart phone and email it might be hard to imagine how isolated we were at Toolik from our family, friends, and colleagues back home.  The mail would come once a week from Fairbanks on the supply truck.  Occasionally the staff in Fairbanks failed to include the mail, saying, “It wasn’t much, so we saved it for the next week’s truck.”  Us Toolikites were less than happy with that.“

Ben reports “Everyone who came to Toolik worked constantly.  The long arctic days and proximity of the study sites meant very productive summers.  However, we did find time for recreation.  We all read lots of books, those we brought and those shared with others.  We wrote letters home.  I would swim a half mile or more in Toolik on most days, once the surface temperature reached 12oC or so.   We played volleyball (Fig. 7.12) with a net stretched across the runway (one time a small plane with engine trouble was almost caught in the net in its emergency landing!).  Our main source of recreation was hiking and camping. We learned the local flora and tried to avoid surprising the megafauna (bear and moose) as we traipsed through the high willows crowding stream banks.  The best hiking was in the nearby Brooks Range. The sliding shale provides better footing than the tussocks of the wet tundra.  Even the caribou avoided the tussocks when they could, favoring the haul road and pipeline pad for easier treading.

Also, Ben recalls that in 1977, Torre Jorgensen, the camp manager built a proper Finnish sauna from items scavenged from the pipeline dump.  Massive oak skids that once bore the weight of heavy pipe were stacked to create a log cabin-type wall (Fig. 7.13).  Torre used large sheets of discarded foam to insulate the sauna. He got a welder to make a wood burning stove from a 55-gallon drum.  As no trees grow on the tundra, we used scraps of timber from the dump for fuel.  We spent many hours sweating and looking out the salvaged back window of a pickup truck that Torre put in the wall facing the lake and Brooks Range.  A steamy hot sauna followed by a jump in the lake was our only means of bathing.  I discovered that not using soap or shampoo left me plenty clean and less attractive to the ever-present mosquitos.

Lachenbruch’s Interactions with Pipeline People and Cold Lake Water

Barb Lachenbruch spent a long summer of 1977 working on tundra seedling growth (Fig. 7.14) when she was 22.  She remembers “Every morning I drove my rig, a pickup truck, from the Toolik Lake camp to my research site.   Leaving camp felt good: I was getting away.  I slept in a noisy tent; all the rain flys had been destroyed by the wind, so each of the 15 to 30 of us rigged up tarps that sounded like shotguns as the wind cracked at them day and night. The tents were up from the lake in the flat areas of tundra scattered close in, but the labs and mess trailer all lined a narrow-abandoned airstrip. Too many people were too loud, day and night in the arctic summer light, with their too weird music and their merriment that had to be exaggerated to be heard over the two generators.  Even though it felt good to get out, getting to my destination cost effort. I had to put the shells back in my shotgun, pull all the gear into the rig, get food for lunch, fill a thermos, make sure I had supplies, then put on my rubberized bib rain-pants and rubberized jacket. I’d walk out into the wind and cold to check the oil and the tires and the gas. It was cold, the rig was cold, the sky was white with cold, and the hills to the west were white through the fog and blowing mist. The Brooks Range to the south might have shown, or might not have, depending on the sky.  I’d have to drive through gates, each with its own quirks of locks and hinges, which meant opening them then driving through then getting out again and locking them behind me. I drove about 8 km toward Prudhoe Bay then I’d turn off the Haul Road into MS 117, a “material site,” or staging area, used first during pipeline construction but still in use for staging. It was used for gravel mining, storage of gravel and metal and Styrofoam parts and trailer units and all manner of odd huge items: staircases, mobile trailers, metal parts of large machines, and wooden ties that had been used to support the pipe during construction. Sections of pipeline pipe lay in orderly rows. There were huge spools, empty or with cable, that towered over my small rig when I would drive by. Trucks would drop off more debris and then spend time rearranging it; I was used to the constant activity focused on MS 117.  I then used a key to get into the Material Site 117, then about 2 kilometers into it I used another key to go through my last locked gate. I wound down across a vale at the head of a tiny branch of the Kuparuk River, then back up and around to where I would park in the roadway. Beyond was a hilltop splay of upland tundra, the shrubs up to my shin. A slanting plain of wet tussock tundra stretched south, east, and west.”

What about any uncomfortable interactions between pipeline personnel and scientists and students working at the Toolik Field Station?  Ben Cuker, reports that “over-indulgence of alcohol was almost expected at a field station.  I recall some pretty wild camp parties fueled by reagent grade ethanol cut with a bit of fruit juice.  I remember only one party we attended at the pipeline construction camp.  Sam Mozley (his major professor) got pretty smashed and almost came to blows with a couple of tough construction workers. “

Steve Whalen, a graduate student with Vera Alexander (University of Alaska), was hitchhiking on the Haul Road and a trucker made sexual advances to him.  Steve jumped out of the moving truck to get away.

Barb Lachenbruch wrote about a bulldozer operator.  “One day a big truck made its way onto the horizon. It approached my site, then parked behind my rig. On its enormous flatbed was a Caterpillar D10, the largest tractor I had ever seen (Fig. 7.15). It rolled off the ramp, then worked its way to a quarry pit a hundred meters away. It worked noisily for about a week. Then the tractor was moved back to the material site and abandoned, another metal item on the fringe of the orderly discards.  A couple of weeks later, I was in my V position, nose down, when I heard a voice. I looked up. Hovering too close to my pile of gear, and between me and my rig, was a scrawny man. He wore coveralls and oversized, bulbous leather boots. The boots matched his face.  “What do you girls do?” he asked. I had always been alone, but he asked in the plural.  “Hi,” I responded, having been taught to be nice to people even when there were warning signs. Besides, where could I go?  I said I lived at the camp at Toolik Lake, which he already knew. I explained I was studying seedling establishment for my Masters degree. That did not appear to interest him.  Then he told me that he and his buddies had been watching me with binoculars from the material site for the past few weeks. He said they knew all my habits—that I kneeled in the mud for long periods without moving; when and where I napped, ate, had my coffee.  It was hard to know what to say. I walked him toward my rig, which I then leaned against. I placed the bag-covered clipboard on the hood. I had left the shotgun next to the plot where he had disturbed me, but I had rolled it in its plastic bag in case there was precipitation. To have taken the shotgun would have appeared aggressive, which I did not dare.  He told me he was ripping gravel. He asked me to come see the tractor close up.  I followed.  He invited me up into the cab.  I climbed up and into the one seat with him. What else could I do?  He said his name was Jack.  Jack-the-Ripper, I thought. But I did not make the joke out loud, in case it was too close to the truth.  He started the rumbling engine. He put down the rippers, which were steel teeth 1.3 m long, that broke up the bedrock into gravel. We lumbered to the center of the pit, ripping rock as we advanced. Then he drove us to the verge, farther, farther–and I thought we’d tip over the slope, tail-over-head. I was quiet; I was still. He edged the tractor even farther.  When the sensations were as bad as they could be–sitting atop a colossal moving tractor breaking bedrock, snuggled tight in the cab against Jack the Ripper, both of us about to tip on the side or flip over, behind two locked gates my campmates had no keys for, and no one keeping track of my whereabouts–he backed the machine, and turned it toward the pit’s center.  We communicated with shouts over the double racket of the engine and the breaking bedrock. He lifted an earpad to listen as I thanked him meekly and said I needed to go. He put down the earpad and laughed, took his hands off the controls while grabbing mine and placed my hands on the two levers. He motioned for me to pull. The teeth pushed hard down into the rock and the tractor surged forward.  Then he directed me onto more of the controls. I was now steering the Cat, controlling its speed, and ripping the rock. I tried to smile. What else could I do? It felt so awful, but it felt so good.  And finally, Jack let me out. I said goodbye and thanked him. He was there for three more days. We waved or nodded a couple of times but said nothing more.”

Lachenbruch has included sections marked by an asterisk in the following: it means they were not a good idea.  “When I arrived at Toolik Camp in late May, the lake was capped with more than four feet of ice, but days were long and getting longer.  That meant I could work all the hours I wanted. It wasn’t uncommon to come back from the field at 10 pm.  I had little internal feedback that I was tired. The light, location, and quests were exhilarating.  Early on, the ice on the lake broke into candle-sized chunks that tinkled against one another, thousands and thousands of tinkles. The melody was so loud I’d turn into the wind to cancel it out, and then, delighted, turn to hear it again.  Leaves came out—virgin, a naïve green. There were new flowers at every bluff or vale—mats of pink, white, purple, or yellow; enormous horns of rhododendron; tiny baubles on spikes; and nodding Arnicas, yellow, like sunflowers. Saxifrages—so many.  And sedges. A pair of least weasels chased one another at my feet over a rushing stream. I walked among caribou, grizzlies, moose, and arctic ground squirrels (siksiks).  Mounds of ice the size of vans, called pingos, would emerge from plains. Rocks on high sites lay in geometric patterns, through thousands of annual nudges of lift from ice and then drop from thaw. Some days, rime ice would fringe the last year’s flowering stalks. Some days were sunny, too. And wind, so much wind. It blew mosquitoes into tufts behind me as I walked.  And my research? Every day was a data day. I got new data that answered questions that hadn’t been asked in all of history and all of time.  I was enfolded into Nature, as a part and an observer. Those two together, I had never been before.

The sun did not set from May 27 to July 17.  I had constant light for almost two months. A few weeks after the first sunset, when days were still with 20 hours of shine, a party was announced.  But I had work to do.  Work was my pattern, my identity, and my joy. And I didn’t appreciate the party because the generator would be on to run lights and radios—the car batteries wouldn’t suffice. The generator was very loud.  The camp manager was off backpacking, and so the passels of PhDs and students and assistants had “free play.” There was nothing wrong with that, except that there was no one in ultimate charge, and it felt to me like a Girl Scout trip without the leader. People got into these parties; they decorated, danced, and dressed up. Outfits might be jockstraps over blue jeans, holsters for field implements, long johns with come-hither rubber boots, and mosquito nets for tube tops over random lingerie. If I could have relaxed that way, it would have done me good.  A quick run would have done me even better.  Running was tricky:  pepper spray against grizzlies, truck-thrown rocks on the Haul Road, and interruptions from truckers who were concerned or curious. But running was out because of my knee, inflamed from long weeks of kneeling on the permafrost at the base of the melted soil.

So, I did what made sense to me. I started the sauna, and then I took a swim. *  The sauna was a small shack (Fig. 7.11) that was built down by the dock, so we could run out of it and fling ourselves into the lake. Its window came from the back of a junked truck. The barrel of water inside, which we called the mosquito breeder, would gradually heat; and a couple of times a week we’d ladle that water on ourselves and each other to slop off the soap and shampoo.  We heated with wood, that is these pieces were about the size of railroad ties, that had been scavenged from left behinds from the pipeline construction.  They were not preserved wood like real railroad ties would have been.   I hoisted a tie onto a pair of sawhorses and sawed off a couple lengths. I split some kindling, started the fire, and hauled a few buckets of water to the mosquito breeder. I undressed to my swimming outfit (the minimality of which I will only hint at here), then waited for the sauna to heat.  When the wind shifted, the music from the party blew my way and echoed under the low ceiling of sky.  Mist blew, mist that verged on ice.  But the sauna was as cold as the outside air.  I went to the path for push-ups and laid down a towel for sit-ups. I tried to nap in the sauna so time would pass, but I was impatient. The sauna had only made it to 44 °F.  I huffed out:  swim first, sauna I decided. I ran down the path, passed the stockpiled beer, and hurdled obstacles down the length of the dock.  Then I dove in.  I surfaced to adjust my goggles and to gasp, even though the lake was warm–55 °F–from heavy rains.  It wasn’t unusual to take a dip after a sauna, and it wasn’t entirely unusual to swim or to swim alone. * I thought nothing of the danger. * But we did have protocols, if not for safety, one of which was to stay away from in situ experiments.  Before the sauna I’d verified where experiments were:  if I swam the near arm of the lake, I’d need to stay 20 or 30 yards from shore.  That’s what I did.

From the first moments in the lake, a cold rind formed around me. I was an orange in a foreign peel. The rind ached, but I was fine: I’d swim through the cold. It didn’t diminish, though, and I swam as well as I could, ears out of the water and face down. That helped.  I reached the end of the bay and then turned back. The dock, a tiny silhouette, was far away. It had only been 300 yards but looked to be a mile.  I swam a few strokes, and looked up, again disheartened. The view swung back and forth. I turned onto my back and drifted. The lake was shallow there, and I had to keep my feet high to avoid lake-bottom slime.  And I was aware of the gentle warmth when I slowed, when I drifted: a boundary layer of water must have given insulation. But I had to swim again.  I turned onto my front and swam a few strokes, then drifted to feel the flame. Stroke and drift. The drift felt good, but I had to stroke, because I wouldn’t float without work. I stroked again, and then drifted.  When I flipped to my back, my vision was off. Things moved right and left, right and left, right and left. I turned to my front and swam and drifted. I’d hardly advanced at all. The shore at my side was close, but I couldn’t go onto those rocks*–experiments, and rocks were so large I would have struggled to clamber up them.  On the horizon was a weather station. I noticed a man there, a non-resident, who’d check the station and drive on out. He waved at me.  He banged right and left, right and left, right and left, right and left. Was I languid as a mermaid? He was gone.  The dock so far away.

A grad student found me when she approached the dock for beer.  I was asleep on the pontoon at the dock’s edge. My head and shoulders were out of the water, but the rest of my body was still submerged. My goggles were still on.  I believe she pulled me out, and then she ran for help. I was propped in a corner in the sauna. * My memories are of people in clothes who pushed me into position, maybe held me upright. * I remember falling sideways on the bench, my head clunking–and that was fine. I remember being given a mug of tea and thinking, what nonsense, they think I can hold this up?  And then I must have been alone again. * I knew what I wanted. I wanted to be outside. * And I escaped.  I lay on a tie. I was on my back. The sky was medium gray.  Sleet and fog blew over me. My neck was arched back in total comfort; my head, my arms, and legs splayed onto the ground. Only my spine was on the tie.

Can you conjure the time when you most experienced bliss? Have you felt suspended among bats of down comforters above and below, your body—and your thoughts, or lack of thoughts?   That’s how I was.  Opposing muscle groups had lost control. I was more than calm. I was more than comfortable. I was more than relaxed. It was rapture, nirvana, sublime.   At some point, people annoyed me. They wrapped my body in a towel. People stumbled me to my research trailer where my sleeping bag was already spread. They got me into my bag on the felt carpet. * The generator drummed loudly nearby.  I looked up at people and at the trailer ceiling, far away.  I recall a research assistant threatening to come into my bag and warm me up if no one else did, but she lay on top of the bag, instead. Someone found a hair drier and dried my hair.  But I wanted one thing only:  the heaven of that railroad tie.

Long hours later, I believe—generator off, light coming only through the window–I erupted in a first shudder. It was a rippling gasp, convulsion, spasm–I don’t know. And then I drifted back to nothingness, to a vacancy from myself.  And after, perhaps long after, I shuddered again. I was aware of something wrong. Myself was “other,” it wasn’t me. That “other” flesh was cold like a water balloon or a pack of meat from the fridge. Another shudder, violent. And then another. And then more frequent. I had shivers with the “gain” turned high. A tinge, so faint, of warmth came to my corpus.

The next two days were in my tent on a mattress on the floor. I could drop my head into a hollow in the mattress that the siksiks had made earlier in the summer. I could drop a leg over the edge. A plate of food appeared from time to time by my feet. I thought my campmates were considering me a rabbit in a cage. There’s much perhaps they did. Mostly I slept. And I remember I had to pee, frequently—those muscles or sensors were disrupted, too. When I tried to stand outside of the tent, I pitched forward. I’d fall on the cushions of tundra, then work my way back to the sleeping bag and sleep again.

On the third morning, a group took me to be seen by the medic at Pump Station 4, which was near a sampling site they had to visit.  The medic asked, “What’s the day today?” but all I could think was, “Every day’s a data day.” He said, “She’s out of the woods, but get her to Fairbanks. People die quickly in the Arctic.” I no longer remember the three-hour Suburban ride north the next day for a commercial flight from Prudhoe Bay.  In Fairbanks, I saw a doctor who prescribed rest. He suspected I was tired; maybe I’d had a virus. As for hypothermia, he couldn’t tell, but years, later a navy doctor said my symptoms were those of classic “cold injury” from submersion.  I pressed her, and she said, “Injury: brain damage.”

My major professor and his wife, a pleasant, ethical, and non-judgmental pair, invited me to stay at their place in Fairbanks for a while. I slept and read two books:  Winnie the Poo, and Plant Strategies and Vegetation Processes; I liked them both, but the second book has stayed with me longer.  After a week, I started to walk outside.  Fairbanks was lush with fireweed, willows, luxuriant grass, and even humid warmth.

After ten days I was well. I climbed into the supply cab for the bouncy ride up, some 13 or 14 hours in that rig. I was back in camp. I finished out the season, but more slowly.  I left in mid-September when days were only 12 hours long, the soil surface was freezing, and the lake’s margins were covered with floating snow.

I didn’t freeze, but the experience was frozen into me. If I hear a certain frequency—an idling truck outside, a ventilation system—I’ll bolt away, or if I can’t, I become nauseated and get a crawling sensation that makes me want to run in circles.  A counselor said it’s from the generator, post-traumatic stress disorder (PTSD).  She decreased my reaction by a lot.

I made errors, lots of them, and so did some people around me, I suppose. But even through these errors, some good came. I visited a mental state so magnificent that now I know this potential, I get comfort in thinking what final rest and release may someday impart. And I have a collateral thought that’s frozen with it, too: that sheer wonder at the opportunity I have each day to solve puzzles never asked before. I have that opportunity because I exist, even when I’m not on the edge of the wilds of the Earth.”

Road Washout

One problem of the early design of the Dalton Highway was the use of large diameter culverts for crossing creek and rivers.  There were washouts that occurred after rainstorms when the river-flow was too much for the capacity of the culverts.  Fig. 7.16 shows a washout at the Kuparuk River, only a few miles north of Toolik Lake, with a boat ferrying people across next to the remnants of a culvert.  Fig. 7.17 shows Mike Abels at the same washout.  The picture also shows a cross-section of the construction of the Highway with large rocks at the bottom, fill, and a gravel roadbed at the top.  The culverts were eventually replaced by bridges.

Ecological Impact of Pipeline and Road Construction

One likely impact of the construction camp operation was on lake ecology.  It is extremely likely that the pipeline workers, especially those who stayed at the camp full time, fished for lake trout.  These workers ran the vehicle repair shops, wastewater treatment plants, and tire repairs, and removed many of the very large and very slow growing adult lake trout (up to 50 years old).  This occurred despite the hunting and fishing ban on all pipeline workers.

Although there is no direct evidence about recreational fishing for lake trout, there is a remarkable data set on changes in zooplankton in Toolik Lake that were very likely caused by a large decrease in numbers of lake trout when the Construction Camp was active.  The data set (Hobbie et al. 2001) and covers the abundance of very large zooplankton each summer from 1976 to 1988.   Here “large” is a relative term as most lake zooplankton animals are very small while these animals were 3-4 mm long.  When Daphnia middendorffiana (Fig. 12.5) were counted each summer (Fig. 7.18), there were ~20/m3 in 1976 but only 0.2/m3 in 1988 (this species is not a part of the direct food of lake trout so are relatively abundant when the large predatory adult lake trout are present and are keeping the small individual young fish hiding along the shoreline.  When the large lake trout are removed, as apparently happened in Toolik Lake during the road and pipeline construction, the young fish thrived and hunted the large zooplankters so that their populations decreased.

Lake and stream chemistry were also affected by the road construction practice of mining gravel deposits.  There are seven of these gravel mines (periglacial kames) in the catchment of Toolik Lake.  The site of some of these mines are “white areas” on the aerial view in Fig. 6.6 along the stream entering Toolik Lake from the south.  When the surface gravel was removed for road construction, the underlying permafrost thawed and exposed previously frozen soil to weathering.  One stream affected by gravel removal still showed elevated concentrations of alkalinity and phosphate 30 years later (Hobbie et al. 1999).  These authors stated, “the stream supplies 5% of the water entering Toolik Lake but 35% of the phosphate.”

A second disturbance from the road was road dust.  Walker and Everett (1987) stated “Since the road opened in 1974, each truck that passes creates a dust plume, especially in the summer. The dust is deposited downwind in a log-decay relationship, where the amount of dust deposited decreases logarithmically with distance from the road.”   They also measured the dust load near Toolik over 96 days to be 200 g m–2 at 8 m and 1.5 g m–2 at 1000 m from the road. One effect is an earlier snowmelt by days and weeks along the road corridor caused by a lowered albedo (reflectance) of the dust-covered snow. Another effect is a change in reflectance of the road corridor caused by read that is visible in summer aerial and satellite pictures. While some environmental changes near the road have occurred (see Leadley et al. 1996), the overall importance of dust deposition is difficult to determine; however, there is no evidence so far of any widespread major changes in vegetation or surface-water chemistry.

Impact on wildlife is a third disturbance.  As noted above, no hunting was allowed at camps or along the road when it was controlled by the construction companies.  There is one picture of a black bear inside a pump station in Cole (1977) and the author states that there were problems with bears caused by improper food handling.  Jeff Cornwell, then a graduate student at University of Alaska, made many road trips north in 1976-1978.  He recalled that “In spring 1978, we stopped into the pipeline camp just north of the Yukon, as usual for a tire repair.  It was a warm day, and a back passenger side window of the crew cab truck was left down.  From the tire repair shop, out of the corner of my eye, I saw a very rotund black bear sprint to the truck and crawl up through the back window.  In the back seat was all the food for our sampling trip.  I had no plans to starve on the trip, so I went to the driver’s side with the window only 1” down and started pounding on the roof above the bear.  He came to the window and growled at me, but I didn’t stop.  He grabbed a loaf of bread and jumped out and ran away.  I walked to the open window and closed it; the bear returned 10 minutes later but realized there was no more free lunch.”

Grizzly bears were attracted to the Alyeska Construction Toolik camp and we have been told that cooks actually fed the bears.  In fact, Bruce Peterson once saw the camp cooks doing just that – they placed meal remains outside where the bears could easily smell it for miles.  With this kind of training from Alyeska cooks, it was not surprising that grizzly bears often prowled around the buildings and tents of the TFS.  And this did not end with the closing of the Construction Camp in the fall of 1976 even though there was no longer any feeding.  Sometimes the scientists had to set up a “bear watch” for warning during the summer research at Toolik.  One persistent bear tried to enter a research trailer in the fall and had to be shot by the graduate student behind the door, Steve Whalen.  And wolves were also affected by the construction, probably from the thousands of lunch remnants thrown away by workers along the pipeline every day.  It was common for scientists making stream flow measurements to see wolves watching them from across the stream.  John Hobbie hiked up the nearby Jade Mt and at the summit had a very close encounter with a three-legged wolf which suddenly jumped up from behind a boulder and limped away.  Nothing more is known about its injury or long-term survival.  Other wolves hung around sites where trucks often stopped such as the Kuparuk River bridge.  When the road was opened to the public, it did appear that the wolves immediately disappeared (hunting, or just disturbance?).  In later years, wolves were sometimes seen or heard but it was not common.

Impact of nutrients on tundra and aquatic ecosystems.  Both the Alyeska Camp and the Toolik Field Station used Toolik Lake for their drinking water.  The wastewater from the Alyeska Toolik Camp received tertiary treatment at the camp and was discharged so that the water flowed into the outlet stream from Toolik Lake and downstream from the lake.  From the 1975 start of the research camp on Toolik Lake, all waste was collected and treated at the nearby Pipeline Camp.

After the Alyeska Operations ended at Toolik in the Fall of 1976, the TFS sewage was picked up and transported to Prudhoe Bay for treatment by the truck that also serviced the pump stations.  This because the pipeline is still operating (in 2021) and a pipeline sewage collection truck still collects wastewater from the operating pump stations and from Toolik Field Station.  This important operation is paid for by the University of Alaska.

Winter Research Trips to Toolik

A year-round study of the phosphorus cycle in Toolik lakes was begun in 1976; field work was led by Jeff Cornwell, a student of Bob Barsdate (University of Alaska).  The unique part of this project was that sampling took place year-round in a series of pick-up-truck trips to Toolik.  In the summers of 1976 and 1977 Jeff reports that he and an assistant made many 1 week-long visits to Toolik camp.  In the summers he says that early in the RATE project, we were the main food lifeline for the camp, and when we didn’t arrive when planned, folks got pretty hungry.  And angry.

Jeff writes: “he, Tom Weingartner, and Lewis Molot made nine winter trips in 1976-1977 (8/29, 9/17, 10/02, 10/24, 12/09, 2/26, 4/04, 5/12, 5/22).  On our October trip, we noted grizzly footprints in the snow near the trailers and took extra care to avoid a surprise.  In December 1976 we were coming down the big slope into Livingood and we slid around a curve into the path of a tractor trailer deadheading back to Fairbanks.  It struck the left front of our crew cab F350 and spun us around, leaving us on the highway 10’ from a catastrophic drop hundreds of feet down to a really bad day.  Eventually a tow truck came from Fairbanks, but I got to spend the day with a AK state trooper before he returned to Fairbanks.  A memorable day.  He was my age, my size (6’7”), moved to AK from Waco TX, and had amazing stories about arresting pipeline workers, mostly from TX and OK, that were riveting.  He said he used a lot of psychology, basically hinting he was going to shoot the man he was about to arrest; it generally worked, and the perp gave himself up.  My favorite line was that “pipeliners don’t understand the subtleties of mace”.

We had a trip to Toolik in February in which we could not get the heat to come on in the lab/sleeping trailer.  At cold temperatures, propane is not an optimal fuel because “ice” forms when it cools during decompression in the regulator and blocks all flow.  We each had multiple sleeping bags and cold weather gear to bundle up in, and we went to “sleep” at -43⁰F and woke up to a balmy -35⁰F.  The pipeline camp gave us space to use for the remainder of the trip.

In 1977-1978 there were seven winter trips with a variety of people, but Keith Mueller from Vera Alexander’s lab and I were on all of them.  Other than a frozen truck in February, the only other notable events were a truck incident and a trip by ski plane.  On one trip, I started driving by 5 am and got well north of the Yukon while the others slept.  Our next driver took off and I went to sleep, to be awoken by a yell of “hold on”.  Our driver fell asleep and drove off the road, but we stayed upright, and upon the advice of a trucker, drove our way back onto the road.

In October 1977, Keith and I did one sample trip using a ski plane, departing in the morning, landing on Toolik near the camp, getting sampling gear, flying to Oil Lake to sample, then Toolik Lake to sample, dropped off our gear, and flew our samples back to Fairbanks in one long day.  We assured the pilot there would be 1 foot of ice on the lakes but, happily, the 6 inches we found was enough.

In 1986 Barsdate won a grant that included me, John O’Brien, Mike Miller, and Sam Mozley to study the effects of oil spills in arctic lakes.  In late summer 1976, the sea curtain arrived, we set it up to isolate a corner of the lake, then dumped 55 gallons of Prudhoe Bay crude oil into this enclosure.   A lot of it attached to the shore and the limnocorral.  We did nutrient chemistry, primary production (14C), temperature, dissolved oxygen and light in 1976/1977 and benthic algal production in 1977.  When I visited a meeting/tour at Toolik Lake in 1994, I kicked over some rocks along the shore and found oil that looked exactly as it did in 1976. “

8.       Facilities at the Toolik Field Station 1976 to 2020

Figures - Facilities at Toolik

From 1976 to 1982

As already described, in the summer of 1975 investigators brought their own tents and food from Barrow for short-term visits to the Toolik Field Station on the narrow runway.  The only facility was a small travel trailer. Facilities improved the following summer, when a large trailer (10x50’) was brought in from Fairbanks that contained a kitchen/dining area, a laboratory room, and a sleeping room.   Food and mail were shipped up by air to Prudhoe Bay until the food package was damaged during transit and leaked all over the mail – hardly a satisfactory arrangement!  In 1978 and 1980, two other large trailers were added to provide research cubicles for the growing scientific staff and in 1982 another added trailer was converted into a wash-up facility.

The challenge of transporting materials into the camp was a perennial issue. One creative solution of staff and scientists for the first several years after 1975 was to search for items at the dump of the nearby Alyeska camp, which was located at the south end of Toolik Lake at the future site of the present Toolik Field Station.  It was not a garbage dump but was used for truck parts, wood crates and plywood, parts of buildings, and the like.  All the dump material was eventually removed after 2000 when the Alyeska Construction Camp was completely removed.  However, the salvaged material was useful for some temporary buildings at the scientific camp – one example was the first sauna which contained several windows from large trucks.

The initial management of the research station was by scientists from the Ecosystems Center of the Marine Biological Laboratory (MBL) in Woods Hole, Massachusetts. John Hobbie, a new hire in 1975 of the newly established Ecosystems Center, had organized the aquatic part of the large IBP project at Barrow (1970-1975).  The logistics for the IBP and for Toolik were based at the University of Alaska, Fairbanks, and headed by George West and David Witt.  The MBL under John Hobbie hired the station manager and cook.  After several years, the station management was turned over to the Institute of Arctic Biology (IAB) of the University of Alaska, Fairbanks, which has proved to be a satisfactory arrangement to the present day.  Mike Abels, present program manager, started working at UAF in 1976 and continued working at Toolik until his retirement in 2021. Brian Barnes (IAB) is the present Science Co-Director.

The UAF sent a supply truck on the 10th, 20th, and 30th of every month (see details later in this chapter).  According to Bruce Peterson, the scientists knew, but management probably did not, that one summer the driver, who was a wintertime schoolteacher, was drinking beer throughout the drive and also peddling pot to Alyeska workers along the road.

Radio Communication: Single Sideband and Meteor Burst

In the early TFS days, the radio communication was single sideband radio which did not work very well in the summertime.  One big improvement was to use “meteor burst” system that used the ion track left by some of the billions of meteors that enter the earth’s atmosphere every day.  These ionized particles last for as long as a few seconds and are able to reflect radio waves between two stations up to 1200 miles apart.  This worked fairly well between Toolik and Anchorage where messages could then be relayed to Fairbanks via telephone.  This was a good method for very short messages and was limited to sending 24 letters until a new contact had to be set up.  But once a San Diego State scientist tried to send a large proposal via meteor burst.  According to Mike Abels, the whole system was kept busy and unavailable for a week before the staff figured out what was happening.

Application of Northwest Gas Company for Toolik Camp and Runway

On 20 January 1982 Terry Chapin, then an Associate Professor of Ecology at the University of Alaska Fairbanks, wrote an urgent letter to C.E. Behlke, the State Pipeline Coordinator, describing the “summer research field camp on the airstrip at Toolik Lake since the spring of 1975.” Further in the letter he says “A conflict has arisen due to Northwest Gas Company having requested a permit to rehabilitate the airstrip and construction camp.  We were advised of this on January 13, 1982.  The B.L.M. intends to review the application … and tentatively to issue the permit on February 2, 1982.”  Chapin is hopeful that the research camp can be moved to a new location on the lake and then lists the 20 different universities and institutions and approximately 1700 man-days of researcher time per year that the camp has served.   These last-minute events are an example of the rapidly developing plans that B.L.M. (U.S. Bureau of Land Management) was responding to and encouraging in the early 1980s and of the uncertain future of the Toolik Field Station.  Luckily, the Northwest Gas Company’s plans and permit did not materialize.

Lapse in NSF Funding, 1981-1982

The Chapin letter described above also mentions an unfortunate pause in the funding for lake research at Toolik: it says that aquatic studies began in 1975 and maintained activity of 1700 man-days per year through 1980.  But an inability to secure funding from NSF or other sources led to a decline to only 180 man-days per year in 1981 and 1982. This aquatic project returned to 1500 man-days in 1983.  Hobbie recalls that these were two summers of low activity and that the scientists in camp decided on several new rules: motorboats would not be allowed on Toolik Lake because it was the drinking-water source and talk about science would not be allowed at mealtimes.  They also made a shift in mealtimes for some reason.  After the funding lapse of 1981 and 1982, there was a long successful history of funding from NSF and other sources.

Food Orders in the 1980’s

Radio communications were a major problem for ordering food during the summer months.  It was decided that the Fairbanks—Toolik trips would take place on the 10th, 20th, and 30th of every month, no matter what!   The food orders depended on notes carried south by the truck drivers.  Then the food had to be bought and picked up in Fairbanks.  Finally, the truck had to be packed and ready for the driver on the morning of the 10th, 20th, etc.; the assembly and packing in Fairbanks were all done by Mike Abels.  He reports that there were strict rules that did not allow him to work on Saturday or Sunday.  Therefore, a Monday trip to Toolik had to be all packed up on Friday afternoon, and so forth.

Decision in 1982 to Move in 1983 to South End of Toolik Lake

The expansion of the Toolik Field Station’s number of buildings on to the narrow runway (Fig. 8.1) meant crowding and no room for expansion except farther and farther down the runway.  See jukebox address and Figures 8.1, 7.9, and 7.10 for a view of the crowded camp in the late 1970’s and early 1980s. is external)

In 1982 the TFS was a part of the Biome Center of the UAF, Terry Koltak was the camp manager, and a cook was also hired.  Mike Abels worked for the Institute of Arctic Biology (IAB) and was saying goodbye to everyone and about to take a job at the Biome Center—but at the last second the Center was merged into IAB, so Mike remained working for IAB.

In addition to the crowding, another factor led the management to think about a new site for the field station.   This was that the buildings and equipment of the Construction Camps were going to be auctioned beginning soon after the pipeline began pumping in late 1976—a wonderful bargain for expanding the living accommodations at Toolik Field Station.  Accordingly, it was decided to more to the new site beginning in spring 1983.

Mike spent part of the summer of 1982 taking down the old TFS and starting the move to the new site.  Terry had inventoried Alyeska’s buildings and equipment along the pipeline and found that a small number of complete ATCO trailers would make excellent laboratories for TFS scientists.  Accordingly, TFS bought 13 trailers at auction for $2,000 each along with things like pumps and water storage tanks.  This upgraded the station as 17 modules were then available.   Truckers were hired to move all these things to the future TFS camp.   Mike Abels reports that four of these very-well used trailers were sold by the IAB in 2019, each for $20,500.   Evidently, they never lose value.

Mike Abels remembers some other events during the chaotic weeks after the final auction had occurred.  First, when the buyers of much of the buildings and equipment realized that there was practically no market for these items up on the North Slope.  Second when the buyers realized that after a certain date the Pipeline Company would charge them to remove these items they had bought.  And third, that they also realized that they could help solve their problem by donating some of the buildings and equipment to the Toolik Field Station.   Suddenly, men with recently purchased equipment appeared at camp with trucks, bulldozers, and donations.  Mike Abels could not pay them but did give them meals in return for carrying out some small tasks including several hours of bulldozing in exchange for a meal.  He also paid them by allowing them to use the laundry facilities.  However, the University soon heard about these deals and insisted that services had to be paid for with cash.

International Permafrost Conference trip 1983

Mike Abels remembers that in 1983 the International Permafrost Association held a large meeting in Fairbanks (IV International Meeting) and scheduled a North Slope tour. This was the first scientific large-scale tour up the Dalton Highway.  Of course, this soon after the 1976 pipeline completion there were no public accommodations and no mass transportation.  To meet the needs of camping, several large tents were bought for kitchens and eight large WeatherPort tents, each 12’x29’, were purchased for sleeping.  A bus was hired for the trip – this was the first bus to make the Fairbanks—Prudhoe trip.  Eight rented outhouses also made the trip; they were affixed onto the bed of a large truck which was moved from one overnight camping site to the next site.  The outhouses remained on the truck and users had to climb up a ladder to reach the truck-bed.

For the tour, large overnight camps were set up at four different sites along the route:  Yukon River, Marion Creek, Atigun Pass, and Toolik Lake.  This last campsite was at the present-day TFS site.  The tents for camping, eating, and personal washup were set up during the late afternoon, used overnight by the people on the tour, and then taken down and moved by the very busy crew after breakfast the next morning.  Mike recalls the Atigun campsite as particularly awful.  After the tour, the eight WeatherPort tents were donated to the TFS.  Because of the excellent facilities at Toolik, later conferences, such as the 2008 Ninth International Permafrost Conference in Fairbanks, only used the Toolik site for a field trip.

Facility Improvements in 1980s

The Department of Energy (DOE) and NSF contributed funds along with The Alaska State Legislature and the University of Alaska to improve the scientific laboratories and kitchen. To minimize impact on the surrounding environment, this included constructing a system to collect wastewater.  A major upgrade was the construction of a large dining area between the kitchen trailer and a communication trailer.

In 1987, the MBL scientists were awarded a five-year contract to set up a Long Term Ecological (LTER) project at TFS.  This contract has now been renewed several times (see book edited by Hobbie and Kling 2014) with the latest in 2018 (Check Date).  Because of this and other NSF projects, the NSF made major contributions for equipment facility improvement.  In 1988, the improvement was for an electrical cable distribution system along with new generators.

Building in 1990s

the scientific infrastructure at TFS was greatly improved in 1994 and 1995 when NSF supported the construction of three 24x60’ laboratories.  These were constructed in Canada and each was made of two 12’ wide sections that were trucked to Toolik.  They included fume hoods, running water, microscope rooms, and rooms for GC and other chemical measurements needed in modern facilities.

In 1999, NSF supported the delivery of four 24x60’ modular laboratories, replacing five older trailers (10x50’).  A modern generator module with two 50kW and two 80kW generators was also installed.

Helicopter support

Through NSF’s Arctic Research Support and Logistics contractor, CH2MHill Polar Services (CPS), TFS is also provided with research helicopter support and its infrastructure is developed and maintained. TFS infrastructure and equipment are owned by either UAF or NSF.   This support greatly enlarged the ability of scientists to look at areas of the North Slope not accessible by road.  For example, an unusually large (400 square miles) tundra burn started by lightning in the very dry summer of 2007 some 50 miles northwest of the TFS has been studied extensively with helicopter support.  Another example is the spring on the Ivishak River studied in detail and at all seasons of the year by Alex Huryn and co-workers, some miles off the Dalton Highway (see Chapter 13 and Huryn and Hobbie (2012)).

Communication Improvements

The next big step in communications took place in the 1990s when TFS obtained permission to use the Alyeska communication system (VHS) that linked the pipeline pump stations.  TFS bought a Yagi (directional) antenna that talked with a similar antenna along the pipeline at the base of the Brooks Range.  As described by Mike Abels, who was the camp manager for two weeks on and two weeks off for six summers, it was a relatively slow system that took all night when someone once tried to send a picture.  Worse, there was only a single email address and the TFS received many emails every day – Mike had to print them out, assign a name for those that only included a first name, and pin them all as a folded piece of paper up on a giant board near the dining room.  He did say that he liked knowing a lot about many people.

After many years, the communication system finally appeared that made the TRS a modern field station!  J. Hobbie recalls the following.  “This system made use of the microwave cable that was situated below ground close to the pipeline and operated by AT&T.  For TFS the problem was the very expensive cable need to reach the three miles between the camp and the cable at the pipeline.  Luckily, when all this was developing, fate intervened.  Congress decreed suddenly in 1998 that NSF was to bow out of its long-term job of administering all the domain names used on the internet.   This is the official story available on the internet.  However, those involved with TFS were also told that when this sudden decision was made NSF still had some funds to use up that were available for various internet applications.  Institutions could apply but an application had to be submitted in a few weeks.  The TFS happened to have a proposal all ready to be sent into NSF for some hundreds of thousands of dollars to make this microwave connection.  Sensing a potential solution to an expensive problem, the University of Alaska moved quickly, NSF approved, and so it happened that TFS had a modern internet connection to AT&T.  The TFS staff and the scientists could suddenly be on the Internet as if they were at their home institutions and in touch with the world.

9.       Ecology of the Toolik Region and Unbelievable Interactions

Figures - Ecology of Toolik Region

Location and Climate of Toolik

The Toolik Field Station (68° 38’ N, 149° 36’ W) is located in the foothills region of Alaska’s North Slope, just north of the Brooks Range (Fig. 9.1, 2.5). In the Hobbie and Kling (2014) book, 59 authors describe details of the regional geology, plants, animals, and climate for this region as well as the ecological consequences of changes.  The online Toolik Field Station website ( has extensive data on the flora and fauna, has maps of the region, and lists of publications on climate, plants, animals, and scientific experiments.

At 68oN, there is no sunlight between mid-November and the end of January. There is, however, a twilight that lasts for approximately 5 hours every day and allows normal outside activities.   The solar radiation that does appear in February and builds to a peak at the summer solstice, is far less intense than that of tropical locations because the maximum sun angle is only 45 degrees at the summer peak compared with the maximum of 90 degrees in the tropics. In addition, because the snow does not melt until early June, the growing season is essentially only June-August.

The year-round air-temperature record began in 1989, several years after the LTER project was funded.  Cherry et al. (2014) present details of the 1989-2010 Toolik climate record that covers 1989 to 2010, with an average annual temperature (at 5 m height) of -8.5oC.  The average monthly temperatures for the year 1997, for example, were Jan -23.4, Feb -20.3, Mar -26.3, Apr -9.7, May -0.1, Jun 9.4, Jul 11.5, Aug 9.1, Sep 2.7, Oct -15.9, Nov -12.8, and Dec -28.3oC.

Precipitation at Toolik (1989-2010) ranged from 249 to 407 mm yr-1.  The annual average was 312 mm and 60% of the precipitation fell during summer months.  Kane et al. (2004) made detailed measurements in the nearby Imnavait Creek watershed for the 1985-2003 period and found precipitation of 359 mm yr-1, river runoff of 181 mm yr-1, and evaporation of 178 mm yr-1.   There was no change in storage.

The 40% of the precipitation that fell as snow was the most difficult part of the precipitation to measure.  The simplest way uses an 8-inch Standard Rain gauge which is an open mouth can with straight sides.  The most sophisticated way is with a Rain gauge shielded by a Wyoming snow gauge several meters in diameter (see Fig. 9.2) that much reduces the disturbance of wind.  Both instruments share similar systematic biases because they disrupt the normal flow of snow in the atmospheric boundary layer and snow preferentially falls away from the gauge. It is also possible, but takes more work, to collect multiple snow samples for a larger area and report the data as the millimeters of water in the snow of a region.  Sturm et al. (2010) included data from Imnavait Creek basin, very near Toolik, in a survey of tundra data on the Snowpack Water Equivalent versus the snowfall depth; as an example of the best fit to the data, 70 cm of snow gave 20 cm of water.  However, multiple samples of snow from a depth of 70 cm gave a meltwater range of from 8 to 32 cm.

The data allow us to ask is the Toolik climate warming and becoming wetter?  Cherry et al. (2014) point out that linear trend analysis indicates that temperature and precipitation at Toolik did not change over the 1989-2010 period.  However, they point out that this is largely an artifact of the shorter period of the Toolik record than of the Barrow 110-year record: the Toolik record is consistent with the Barrow record over their period of overlap and Barrow does show a long-term warming trend and an increase in snow-depth over its entire record.  Thus, it is very likely that there is climatic warming and an increase in precipitation occurring at the Toolik site.

Growing season’s length, the number of days in a year that the average daily temperature is above freezing, is 123 (± 3) days.  As was the case for temperature and precipitation, there was no statistically significant change in the length of the growing season over the sampling period.


There is permanently frozen ground (permafrost) beneath all the Toolik region down to a depth of 200 m.  On the North Slope the depth varies from 90 to 600 m; at Prudhoe Bay on the coastal plain it is at the maximum of 600 m.  It is well known that this permafrost is warming relatively rapidly.  For example, Romanovsky and Osterkamp, quoted in Cherry et al. (2014), made annual soil measurements near Galbraith Lake, 20 km south of Toolik, and found that permafrost temperatures at a depth of 20 m increased significantly by up to 1.0oC over the past 20 years (Fig. 9.3).  Temperatures are taken at 20 m depth in the soil because at this depth seasonal changes are damped out and climate trends easier to determine.  And, as expected from air measures, the temperatures at Barrow are colder by nearly 4 degrees.  The evidence from the Toolik region, then, does agree with the large summary of arctic data published by ACIA (2004); the conclusion is that arctic air temperatures have increased by 2-3oC in the latter half of the twentieth century.

Sometimes, when the surface soil freezes it forms cracks.  These cracks allow water to penetrate into the permafrost and form ice inclusions (Fig. 9.4).  When this ice melts, erosion of the soil can destroy the foundations of buildings and roads in towns of northern Alaska.

Surroundings of Toolik Field Station

As seen in Fig. 9.5 and 9.6, the station is located amid rolling hills to the north of the mountains.  The current station (2020) is shown in Fig. 9.7.  During the oldest glacial periods, more than 100,000 years ago, the entire landscape was covered by ice extending out from the mountains (Fig. 9.8A).  In the most recent ice extension (Fig. 9.8B), the ice covered the lower elevations now occupied by Toolik Lake and the surrounding hills (less than 25,000 years ago).  Pieces of ice covered by glacial till eventually thawed and created the lake basin.  The earlier glaciations were massive; ice flowed in glaciers down the present-day river valleys as far as 50-60 km from the edge of the mountains.  The most recent glaciations, ending around 12,000 years ago, reached only as far as the Toolik region.

The present landscape consists of a diverse mosaic of tundra ecosystems.  The very different landscapes shown in Fig. 9.8, are within a few miles of one-another.   Shaver et al. (2014) describe the dominant plants in these ecosystems as evergreen, deciduous, or graminoid, woody or herbaceous, vascular or nonvascular.   Trees are absent except in isolated patches along rivers.  Annual plants are very rare.  Plant distributions within these ecosystems are controlled by a moisture gradient from dry in the uplands to wet in the lowlands and a soil pH gradient related to how long since the departure of the glaciers. Every spring the soils thaw to a depth that varies from 30 cm to 1-2 m, depending upon a wide range of drainage conditions, amount of organic matter in the soil, and amount of vegetation.

Cotton grass (Eriophorum vaginatum) (Fig. 9.9) is a sedge that forms large areas of dome-shaped tussocks that average 20 cm high.  Remarkably, these tussocks average 158 years old.  Tussocks are very difficult and exhausting for animals and people to walk on.  Heath tundra (Fig. 9.10) is composed of short plants such as dwarf birch and crowberry.

To carry out ecological studies near TRS means using boats docked at camp for lake work or using trails to walk out to the research sites.  During the six weeks around mid-summer the abundant mosquitoes mean that special clothes and head-nets must be worn (Fig. 9.11).  Boardwalks must be used to avoid destroying the vegetation and allowing paths to cross moist tundra and even very shallow ponds (Fig. 9.12).  There are miles of boardwalks over the hills near the camp.

Animals Found Near Toolik

The Environmental Data Center (at maintains lists of birds and mammals seen at Toolik along with descriptions, pictures, vocal recordings, and more.  In the Toolik region 127 bird species have been seen.  One beautiful rarity, the mysterious bluethroat, breeds only in a small area of the Brooks Range and then migrates back to Siberia and likely winters over in Southeast Asia (Fig. 9.13).  Twenty mammal species have been seen; 14 are common.  For example, the Alaska Marmot (Fig. 9.13) lives on Slope Mountain and in Atigun Gorge.

Some small mammals are very common such as the voles and lemmings which sometimes reach 50,000 per km2.  Caribou have an abundance of 1 animal per km2 (see description of their migration in Chapter 3 about massive migration in 1958).  Huryn and Hobbie (2012) looked at these statistics from a different perspective and said “consider a 200 m wide swath of the North Slope along the Dalton Highway from Atigun Pass to Prudhoe Bay.  This swath, which provides 100 m of easily scanned terrain on either side of the road, will likely contain as many as 250,000 voles and lemmings, 54 caribou, 5 red fox, 3 moose, one wolverine, and even fewer muskoxen, grizzly bears, and wolves.”

Wolverines are year-round predators of small mammals across the Arctic and opportunistic predators of larger animals.  In this respect, they are naturalists themselves, carefully observing those who might be sick or injured. In this rare picture of a wolverine and its potential prey (Fig. 9.14), it has found a male caribou who looks all right but cannot move well and soon died.

Wolves are always after caribou, but a single wolf can only watch (Fig. 9.15).

Dall Sheep are abundant in the mountains and need steep terrain and cliffs to avoid wolves and grizzly bears (Fig. 9.16).   This population on Slope Mountain is of young and mothers.

Muskoxen were wiped out in Alaska in the 1800s but were reintroduced to islands in the Bering Sea in 1930.  In 1969, a group of 53 were moved to the eastern North Slope where now around 250 survive, mostly in the foothills.  They are often spotted from the Dalton Highway (Fig. 9.17).

A male grizzly emerged from swimming across a major river at midnight – he floated high enough to stay partially dry (Fig. 9.18).  Mac Butler describes this event later in this chapter.

Tundra Fires Near TFS

Beginning in in 2004, several small tundra fires occurred on the North Slope and in 2007 there were three other small fires with a total area of less than 1000 ha (Fig. 9.19).  Tundra fires had occurred in the past but very rarely and none since the start of TFS.  There was, however, one very large fire in 2007 that lasted for three months and consumed more than 1000 square kilometers (Jones, Kolden et al. 2009).   This fire was near the Anaktuvuk River and accessible by helicopter from the TFS.  Remarkably, in some of the regions of the fire the tussocks did not burn completely (Fig. 9.20) and were able to resprout even though the surrounding organic soils were consumed.  In other regions, the fire was so intense that the organic soils were completely consumed and the iron in the soil was oxidized (Fig. 9.21).  The very low rainfall and high temperatures of that summer undoubtedly contributed to the fire severity. Jones and Kolden et al. (2009) point out that this was a summer with a record warm average temperature and a record low rainfall, but it is not clear exactly why there were three very small fires but only one monster fire.

Observations and Experiences of Staff and Scientists

Erik Hobbie, who has published a number of papers about fungal ecology at Toolik and helped edit this book, writes the following.  “Our contact with nature has been decreasing for the last hundred years and this decline has accelerated during the computer age. For example, mentions of nature in popular songs have decreased by half since the 1950s, and scientists are not immune to this trend in society. Yet, there is an inherent love of nature in us all – what E.O. Wilson termed “biophilia”. This love of nature is part of what has drawn scientists back to Toolik for decades – not just the research opportunities, but the chance to step away from the pavement and right angles that dominate their lives during the academic year. What visitors to Toolik have seen in this mostly untouched wilderness reminds us that the birds and mammals have their own goals and behaviors – hunting, fleeing, fighting, mating – that are not too different in some respects from our own.” Although the birds, bears, caribou, and other animals have been described in scientific papers, even the natural history book written by Huryn and Hobbie (2012) did not have room for most of the interesting events and animal behaviors.  One reason that the Toolik people have success in seeing the wild animals is the tremendous amount of time they spend in the field carrying out the scientific measurements – collecting in a plot of tundra, sampling along a stream, or sampling fish migration.  And, of course, they have a long tradition of hikes in the Brooks Range every Sunday.  These hikes have covered all the mountain valleys, lakes, and even glaciers that are within hiking distance from the Dalton Highway (Fig. 9.22).  It is also true that any encounters with grizzly bears are never casual and are never forgotten.  At Toolik Field Station in 1975, the scientists encountered bears who had become habituated to humans because of indiscriminate feeding by cooks at the construction camp.  As a result, the bears often visited the TFS in the early years of the camp; with the strict regulations on waste food disposal since 1975, such visits are fortunately now very rare.


In their book, The Mammals of Northern Alaska, Bee and Hall (1956) use all the available scientific data as well as the knowledge of the Inuit people mostly from Point Barrow.  Grizzly bears are omnivorous, large (6-6.5 feet in length, 300-600 pounds in weight), hibernate from the end of October until the beginning of May, and are not usually aggressive towards man unless their young are threatened.  They do eat the dead caribou left behind in the passage of the giant herds through the foothills and mountain valleys.  They also raid food caches and uninhabited camps.

Bruce Peterson.  Hiking along a mountain stream, was surprised by a grizzly coming up behind him—evidently the bear was following the scent of grayling guts that Bruce was using as fishing bait.  Peterson watched cooks from Toolik Alyeska Camp feed bears with food scraps outside a dining room.

Terry Chapin and Alan Mark, now well-known scientists, were camping in a pup tent when a bear sat down on one end of the tent – unfortunately, partially on top of Terry.  Terry yelled a lot and the bear retreated.

Jeff Cornwell and Hobbie made a trip north in the early summer of 1978.  On this particular drive north, while in the southern foothill of the Brooks Range, we suddenly came upon 3 young, but still pretty big, grizzly bears who decided to sprint ahead of us on the road >30 mph rather than cut across the road.

Hobbie writes about the 1980’s: I was up early one morning and washing up in the old wash trailer in our new TFS location.  Suddenly I saw a bear walking steadily towards the sauna and the nearby tent-campers.  I ran over to the cookhouse where Fast Eddy was cooking breakfast for the camp and asked him to bring his gun and help watch the intruder.  Eddy said no, he was too busy.  So, I hurried over to the array of trucks and finally got one to start—I was excited and drove over to the camping area where the bear was by then strolling along next to the lake.  I started to turn the truck around but was too excited, backed into a ditch, and was stuck.  I then shouted about the bear and began tooting the truck horn.  Mike Miller jumped out of his tent in his usual sleeping costume (i.e., none) and shouted, “There’s a bear in tent city, There’s a bear in tent city”.   The bear was not perturbed, continued quite steadily on his walk and ended up along the high willows at the main inlet to the lake. Later, all banged on pots and the bear crossed the stream and walked away.  Mike Abels reports that he was at this event but came out of his trailer with a shotgun and revolver when the bear came over to camp in the early evening.

Neil Bettez and Jacques Finlay were on a camping trip and hiking in a Brooks Range valley one very windy day.  They were making lots of noise to let any bears know where they were.  Suddenly they came between a mother and her two cubs.  Jacques was knocked down by the mother (luckily, he had a big pack on, and she attacked from the back.  The bear then grabbed him by the shoulder (it left an imprint of its teeth but did not penetrate his skin!).

There are also bear pictures in Chapter 4 taken where Hobbie and Jaap Kalff were at Shublik Spring. (Canning River in ANWR) in July 1969 and watched mating behavior of bears (4 figs).  It began when they saw a female with two yearling cubs moving slowly up a hill about ½ mile away.  These were soon followed by a fast-moving male bear and then, yet another male caught up and a fight began.  Unfortunately, the bears were just slightly over the edge of a hill so we could see them only at the several times when they reared up and clawed at one another.  Soon a single male bear headed uphill after the mother and cubs and the other bear stayed near the fight-place and licked his paw.  When the uphill bear came within a hundred yards of the mother and cubs, yet another bear came running up the hill (was it the same already defeated bear?) and these males proceeded in a downhill chase.  By chance these two bears ran towards us.  At first, we were not worried as they were at least a half mile away and there were several stream valleys for the bears to cross.  But they moved fast and always seemed to head directly at us.  I had a rifle along but mentioned to Jaap that it was too bad that I had never actually fired that gun.  Jaap replied that the bears were close enough that he had to start focusing the camera lens.  Finally, from about 100 feet away the lead bear saw us, stopped, and stood up to look.  Then he started to run away followed by the second bear.  They ran up a nearby hill and a caribou herd up there ran before them.  The herd split and half went up the skyline and half went down the skyline and the bears ran up the middle – what a sight! This series is in Chapter 4, figures 14, 15, 16.

Steve Whalen was forced to shoot a bear that tried to break down a trailer door.  Apparently, Steve was on top of the trailer and shot downwards through the top of the door.  One version adds the detail that Steve had an earlier injury that greatly damaged his ability to smell.  For this reason, he did not realize that an old refrigerator in the trailer contained some old rotten food.  This ancient food was the reason that the bear was attempting to enter the trailer.  This all happened during the winter when camp was closed.  Steve chopped a big hole in the ice sheet and stuffed the carcass of the bear under the ice.

Terry Koltak was the camp manager when Toolik camp was still located on the old runway.  He had to shoot a bear early in the season that had found some frozen food inside two trailers.

Mac Butler spotted a big bear while driving back from Prudhoe with Dave B. and Pete S.  He said that had we been tundra hikers, we surely would have been less enthused. But feeling invulnerable in our crew-cab pickup, we eagerly rolled down windows, pulled out cameras with telephoto lenses, and cranked through film. The bear meandered southward between the Sag and the Haul Road, angling toward us as it explored the tundra for a ground squirrel or other snack. Showing no awareness of the truck, the bear was just doing its ursine thing, seemingly oblivious to our increasing proximity; I recall my astonishment when the huge bear suddenly sprang across a small tundra gully – as quick and agile as a cat!  Only when it neared the edge of the road pad did the bear show any sign of concern. Sniffing the air with nose high, it cautiously came up the snow-covered bank and nervously crossed the road just a stone’s throw ahead of our truck – then headed west across the tundra, the midnight sun glowing on its blond back. Clearly this bear had recently swum a channel of the Sagavanirktok, his lower two-thirds still damp while the blond fur on his head, hump, and rump looked freshly blow-dried (Fig. 9.18).

Mac continues.  On previous trips from Toolik to Prudhoe that June of 1980, I had noticed a wanigan-structure (a small, portable shelter) at the end of a spur running west from the road. Someone told me that it housed a Battelle research crew studying road effects on birds and small mammals. We had just passed that spur and realized that the grizzly was now headed for the wanigan! There was no truck parked at the site, and we feared that with no one at home the bear might tear into the structure. We also viewed this as a golden opportunity: We could try out our “bear bangers” on a real bear, from the safety of the truck - not while cowering in terror out on the tundra!  We backed up and turned down the spur toward the wanigan, readying our bear bangers. But the grizzly was on to us and veered away to the southwest. Just then, the door to the wanigan opened and a stunned young man peered out, nervously brandishing a CO2 fire extinguisher. We joined the two occupants inside and heard their side of the tale. They had just smoked a joint before bed, when Dave looked out the south window to see the bear heading for their door; he could not see our truck approaching from the east. “Where’s that shotgun!” he called to Craig. “In the box under the bunk!” replied his companion. As Dave found the box and frantically assembled the firearm (perhaps less frantically because of the joint), Craig took up a defensive position inside the door, armed with the fire extinguisher.  We all had a good laugh, imagining a person attempting to take on a big grizzly armed only with a cold fog of CO2. Like nearly all North Slope grizzly encounters, this one ended with a good bear story for all involved, and no injury to man nor beast.

In the summer of 1977, Mike Miller was running a pond experiment and had left a large number of plastic 1-gallon Cubitainers incubating in the shallow waters of Camp Pond quite close to the old Toolik Camp.  One day a bear came by and deliberately smashed one-by-one all of the Cubitainers while the staff watched from the top of the trailers.

Gus Shaver recalls that once when a bear would not leave the old camp, all present formed a long line and advanced while each banged on a pot, pot lid, or other noise-making thing.  The bear retreated and eventually jumped into the lake (near the outlet) and swam across.

Donie Bret-Harte was on a hike with John O’Brien and others up Slope Mountain.  She said “we walked up the stream to come to the high benches in a more gradual manner, through a shallow valley.  As we emerged from the stream onto a bench at the beginning of that valley, we saw a blond mother bear with three cubs across the bench.  We waved our arms and tried to look big.  The mother started rounding up the cubs to leave.  One cub was too interested in us, and the mother had to swat it across its rump several times to get it to run away.  It gave quite a yell when she swatted it.  They all ran up the other side of the valley and disappeared.

Parke Rublee writes:  Can’t remember which summer (may have been the same one Gus recalled when we all formed a line and banged pots), but across the small bay of Toolik Lake and along the shoreline from camp, Gus Shaver and his group had a number of Tundraminiums set up - temperature change experiments I believe.  Several of us were outside over on the camp side when we saw a bear approaching one of the field staff at the Tundraminium site.  The bear was on a line straight toward the person, and although he seemed unaware of the approach—and the bear did not seem intent on him—we could foresee trouble.  Most of us had no idea what to do - except John O’Brien.  He ran down to the dock, fired up the engine on one of the boats, motored across the inlet and rescued the researcher.  Ultimately the bear ambled off over the hill and out of site.  One of the many times I was impressed with John O’Brien over the years for his quick thinking and concern for others.

Dan Sperduto recalls the 1986 hike with Tim Yandow.

Dan:  This was a day hike up Trevor Creek —along with Jim Laundre, Alexa McKerrow, and Sue Cargill. Tim and I were angling to climb one of the peaks accessible from the valley and had ice axes and crampons to navigate the steep snowfields en route. We went up-valley a good way with everyone, each making noise, singing loudly whatever nonsense we thought would best discourage bears. One of the oft-repeated refrains we had become accustomed to shouting was something along the lines of “oh, hello mister and missus bear...I am not a caribou”. We reached a point where Tim and I split off to head up to the destination summit off to the south side of the valley, while the remainder of the group headed up the main valley to a separate high point. After summiting, we decided to descend back into the creek valley by a different route, across and down a broad scree slope. Near the base of the slope the route funneled into a narrow rocky gap or gorge above the main willow-choked creek valley. Tim and I chatted idly as we approached the base of the rocky funnel, not really shouting any bear warnings as we were in otherwise completely open terrain.

Tim: I remember the bears suddenly appearing over a knoll in the middle of the gorge. We could not really see down into the gorge because it steepened just beyond this point.  We were only maybe 50 feet from the mother bear when we first saw her, with two cubs in close pursuit.

Dan:  We were both astounded by the speed of the threesome, fluidly loping upslope with commitment, heading straight at us. I was a little ahead of Tim, and I began to run across slope perpendicular to the bears’ approach, thinking if I could only make a little room for passage, we could all cordially pass one another and be on our respective ways. This did not occur to the mother bear, as she immediately followed me in pursuit, and it was absolutely clear in that moment that I would not escape her approach. So, I turned and faced her, raising and waving my arms about madly and shouting at the top of my lungs. I remember thinking with certainty, wow, this is it...this is how I am going to die. What I didn’t know until after, according to Tim, was that I was shouting “I AM NOT A CARIBOU!! I AM NOT A CARIBOU!!”. Apparently, this was the right thing to say, as the bear got to within 15 feet or so of me at full stride, and in one continuous motion growled, wheeled and turned on her hind legs, circled in front of me, and then focused her undivided attention on Tim, who was perched on a small rock nearby, screaming and waving to the best of his abilities.  The bear approached very close to Tim... he could have taken a step and kicked her as I recall. Wisely, he stood his ground, and the bear again reared on her hind legs as she considered Tim, then turned swiftly upslope, perhaps by then sensing we were not a threat or worth the bother, and her cubs had started to angle safely upslope past us anyway.

Tim: Dan was indeed ahead of me so even closer. The “I am not a Caribou” shout is absolutely true!! It was a comic moment in the midst of one of the most terrifying events in my life. When the mother bear circled around in front of Dan and then headed for me, I remember vividly having the urge to run, then quickly realizing how pointless that was, getting up on a nearby rock, which could not have been more than 12 inches in height, and letting out a yell I did not know my body was capable of producing. But she kept coming and I recall having a moment of complete peace. My body completely relaxed as I surrendered to the inevitable contact we were about to have when she indeed swerved just a few feet away from me and headed up the hill to rejoin her cubs. I remember the mother bear and her cubs stopped at the top of a rise and turned back to look at us and we at them. This lasted maybe 10 seconds at most. Then they turned and disappeared. I remember I started trembling and Dan and I embraced a few moments later in disbelief that we had come out of that whole encounter without a scratch.

Dan: The whole event began and ended in probably not more than 30 seconds. A minute or two later, the three bears were distant specks high on the slope above us. After some speechless moments on site absorbing what just happened, we continued into the valley where we soon encountered the rest of the group. We decided what must have happened was that the three hikers in the main valley had spooked the bears down-valley as they descended, and the bears had turned up the funnel-drainage to escape encounter, inadvertently sending them straight at us.

Tim: I also recall the camp manager asking us, once we recalled the event back at Toolik, if we had taken any pictures? That became a sort of running joke connected to the encounter, along with the question of whether or not either of us had a gun. My response was even if I had, I would not have had time enough to shoot myself or Dan!


At Green Cabin Lake Bruce Peterson and Linda Deegan watched two wolf packs on opposite sides of Green Cabin Lake howl at each other for an hour.

Dan White reports that a research tech brought a musical saw up to Toolik one summer.  One evening he heard her playing while she was sitting on the dock at camp.  And the earie sounds from the saw were being answered by a wolf howling on the other shore.  During a few years there was an active wolf den close to the “N” lakes.

Chad Diesinger on 20 January 2019, writes that it was -30oF on this day. During the morning hours, staff (only three of us were in camp on this date) observed caribou crossing Toolik Lake.  They seemed to be in quite a hurry as they were running at a fast pace. Russ (CPS Maintenance Staff) had asked me if I had noticed anything that would have startled or scared the caribou to increase their pace which was faster than their normal traveling speed. I had not. We had observed wolf tracks around on the lake and the access road to the north end of Toolik Lake earlier in the week. Glenn (TFS Maintenance) had even used his tracking skills to determine there was a group of wolves apparently following the caribou and Glenn had estimated there were six of them from his tracking. I had planned to do one of my standard ski tours which travels across Toolik Lake, and then across Lake S3 and winds through the moraine hills before dropping onto and crossing Jade Lake and then up what I refer to as the central valley of Jade (between the east and west summits of Jade mountain) and then following a vague ridge up to the east summit of Jade, before dropping off the south side of Jade and contouring around back to Jade Lake where I would pick up my ski track to return to camp. I had made it over through the moraine hills and was focused on the tricky, steep and icy descent onto the lake with my skis making considerable noise with the edges scratching along the ice as I wedged to keep my speed under control. As I made it onto the level lake surface my now parallel skis became quieter allowing the wild and unmistakable sound of wolves howling to register in my brain and elicit the primal instincts to kick in as the hair on the back of my neck bristled.  My immediate fight or flight instinct had my eyes scanning the surrounding landscape and quickly identifying the location of the group of wolves that were no more than a quarter mile away at the edge of Jade Lake.  I was relieved to see the wolves were not heading in my direction but obviously reacting to my presence on the lake with their howling (this is at least my interpretation of their howling), as they mingled in a close grouping and continued to vocalize for about two minutes, including the howls, yips and strange sounding, growling grunts (from just two of the group) that finished off their collective chorus. This was an amazing sound to hear and despite this rare experience that I was appreciating, the realization that I was definitely vulnerable being that I had no real self defense mechanisms along with me, had my mind racing as to what my reaction should be? I quickly skied to the closest edge of the lake and climbed up onto the slope to maybe appear larger but also to get a better elevated view while the pack decided what they would do. They began to move up the slope next to the lake and spaced themselves out as they began to move to the south along the ridge referred to as the heath highway that lies just east of Jade lake. I was then able to see there were six individuals and the leading wolf was very dark colored and the others all varying shades of gray. I was relieved that they were heading in the opposite direction as me but wishing that I was able to continue this encounter as it was obviously unique and very exhilarating. As they moved further away, I thought about what I should do...continue my ski or head back to the safety of camp. I decided that my interpretation of their vocalizations was simply to stake their claim to the east valley where caribou were definitely present, and they were apparently hunting. I also decided I would continue on my ski tour but would change the objective from a loop that would require me to ski through the east valley, where they had headed and instead, go to the summit of Jade and return back down the central valley to avoid disturbing their hunt. I did make a side detour after gaining some elevation in the lower part of the valley to track the packs progress and ensure they were still headed away from the direction I was headed. After confirming that they were not circling back in my direction I skied up and then back down the central valley of Jade, riding a serious adrenaline rush from the wild encounter. After returning to camp, I did some internet research into why wolves howl and found that along with helping other members find the group, wolves will howl to warn competing packs to stay away and to mark their territory. This was how I interpreted the packs communication and was happy to let them have the east valley all to least for the day. Later this winter, in March, when the Caribou Nutritional Landscapes group were out doing field work west of Toolik, in the Itkillik River drainage, they also had this same group of six wolves with one dark individual visit their camp and serenade them with a chorus of howls.

Hobbie watched from the camp dining room deck as a wolf pursued a lone caribou along the inlet stream and then along the shoreline of Toolik Lake.  The caribou plunged into the lake and swam about ½ mile to a shoal area where it stood for many hours.  The wolf stopped but then kept going along the lake shore.


Gus Shaver recalls that in 1977, camp manager Torre Jorgenson would feed a red fox that came by every evening.

In 2014, a female fox and her kit moved into camp. They spent the summer living under the weather-ports and hunting the local ground squirrels. The kit, named “Billy the Kit”, captured everyone’s hearts with his cuteness.

Jim Laundre was hiking in the mountains with Tim Yandow and Mike Miller when they spotted a moose being chased by a wolf.  A closer view revealed it was actually a wolverine chasing a caribou.

John Hobbie remembers observing a falcon ‘contour cruise hunting’ in early spring of 1961 in the Lake Peters valley in the Brooks Range.  This means that fast birds of prey will often fly very close to the ground while hunting, hoping to surprise a small mammal or bird.  I was watching via a telescope while an all-white gyrfalcon contour-cruised along the upper reaches of a snow-covered slope about a mile away from the camp.  Suddenly, in the same scene I could see the gyrfalcon in the air and a wolverine on the ground.  I then watched while the wolverine tobogganed down a long mountain slope with only its head showing above the snow.  It was as if it was swimming.

While hiking to investigate a new thermokarst feature on a lake in the headwaters of the Oksrukuyik River, Jason Dubkowski, Will Daniels, and Dan White watched a wolverine harassing a male caribou – the caribou only moved slowly as the wolverine made several rushes close by (Fig. 9.14).  After noticing the researchers, the wolverine spooked and ran off. The caribou limped to a willow thicket on the edge of a nearby lake, where it collapsed and died.


Moose were not present in the eastern North Slope regions during the 1958-1961 thesis research by Hobbie.  However, while flying in small planes from Lake Peters to Barrow, he observed moose west of the Colville River.  In 1969, Moose were present along the Canning River 25 miles west of Lake Peters and along the pipeline road in 1975 and afterwards.

Hobbie and others in summer of 1995 (a summer of incredibly dense mosquito swarms) watched a male moose spend several days in the shallows of Toolik Lake with only his nose sticking out to avoid the mosquitoes.  Another observation of the mosquito effect occurred in the same summer when a male moose stood outside a large garage directly in the exhaust stream of a large fan inside the Alaska Department of Transport camp near the Sag River.  This moose appeared to fear the mosquitoes more than he feared us, as he did not move even though we were refueling our truck less than 100 feet away.  Finally, early in that summer we saw a female with two young calves near Imnavait Creek.  There were no further sightings and we believed that the calves did not survive this unusual summer.  In the same summer, there were no such swarms of mosquitoes on the South Slope of the Brooks Range.

Hobbie and Jaap Kalff (later professor at McGill University) were hiking in the summer of 1969 along a stream flowing from Shublik Spring (just east of the Canning River, 100 miles NE of Toolik) and bordered by 6’ high shrubs.  Hobbie recalls that he almost stepped on a moose calf lying amongst the sedges and low shrubs – the calf never even moved but we left immediately.  I remember wondering for a second or two what the animal was in front of me because all I noticed at first sight was two extremely large ears.  This was an extremely dangerous situation but luckily the mother moose was nowhere to be seen.  The Alaska Department of Fish and Game says, “more people in Alaska are injured by moose than by bears each year”.   A University of Alaska scientist has stated that an enraged mother moose can be the most dangerous animal in Alaska.

Dan White reports a moose encounter that happened to Cody Johnson and Maya Wei-Hass while they were surveying a lake in the Anaktuvuk burn area.  Maya was performing bathymetry measurements from an inflatable raft when she noticed a cow moose feeding at one end of the lake. When Maya’s work brought her close to the cow, it stopped feeding and charged into the lake after her.  Maya, who had been on the Smith College Crew team, managed to escape by some speedy paddling.


On July 4, 1958, Hobbie watched a large herd of tens of thousands of caribou move through the narrow mountain valley of Lake Peters, a 4-mile-long-lake some 125 miles northeast of Toolik.  The animals were a part of the Porcupine Herd which migrates to the southern Brooks Range.  Our camp was at the tip of an alluvial fan that extended from the edge of the steep mountain out into the lake (Fig. 3.11).  After several hours, the herd extended the whole length of the west shoreline and began to cross the inlet river towards the research camp. The herd surrounding us was probably 10,000 to 20,000 animals (in 2017 the estimated size of the Porcupine Herd was 218,000 animals in Alaska and Canada, the largest herd of migratory animals in the world).  Several times during their passage, a group of 500 animals or so would dash up the mountain or suddenly swim across the lake – these are usually led by several animals and the rest just followed.  The front of the herd came toward the research camp late in the afternoon and a grizzly bear suddenly walked across the upper edge of the fan just before the forefront of the herd was seen (Fig. 3.23).  This bear moved along the top of the fan for a short time and then disappeared behind a large rock.  The herd then moved to cover the entire alluvial fan between the camp and the bear’s hiding place and then stopped to graze and rest for the night.  Around midnight we saw the bear walking through the herd – which parted enough to make a several hundred-foot-wide passageway as the caribou calmly moved out of the way.  The caribou behaved the same when several of us at the camp also walked through the herd.  After the herd moved on there were three or four dead animals around and in the lake.

Larry Hinzman recalls: “I could smell them before I could see them.”  He is Vice Chancellor for Research at the University of Alaska Fairbanks.

In late November 1984, I was still early in my PhD program at the University of Alaska Fairbanks.  I was a graduate research assistant in the Water Research Center under the supervision of Professor Douglas Kane.  We were part of a large collaborative research program called R4D (Response, Resistance, Resilience and Recovery from Disturbance) funded by the US Department of Energy and taking place in the northern foothills of the Brooks Range, about 10 km from the Toolik Lake Research Station.  Our contribution to this comprehensive program was to characterize the hydrological and meteorological processes in the Imnavait Creek Watershed.  Although there was some information on point measurements of river discharge and of air and soil temperatures, there was little data on year-round processes.  This was surprising in that the first barrel of oil had passed through the trans-Alaska crude-oil pipeline only seven years prior and the pipeline crossed Imnavait Creek about 2 km north of the study area.  The purpose of the R4D project was to develop a comprehensive and quantitative baseline characterization of the physical and biological processes occurring in the watershed and then disturb the system somehow to enable measurement of impacts and recovery.  However, we were in such a state of early discovery and understanding of the interactions and range of variability of processes, that disturbance studies were never conducted. Still, we produced a treasure trove of critically important publications and thereby established the state of an undisturbed system in the mid-1980s. These baseline publications have enabled the evolution of the Alaskan Arctic North Slope to be understood in all its complexity of interacting physical and biological processes.

This was an exciting time to be involved in field research in the remote Alaskan Arctic.  Solid state electronic instruments had only recently been introduced to the commercial market and our team was among the first to abandon paper charts and wind-up clocks to use digital data loggers.  Such data loggers are now both ubiquitous in field campaigns and very reliable, but this was still a time when our confidence in the new equipment was low and the complexity of programming the mini computers was high.  Consequently, there was much over-engineering and occasional losses of data.  We were uncertain that the data loggers could operate at such low winter temperatures, so we devised complicated systems of embedding heat sources, adding substantial battery back-up, and placing large snow fences upwind to bury the logger boxes in deep snowdrifts.  Mechanical clocks and charts regularly failed in extreme cold, so our caution was not without reason. However, failures were generally driven by human error or vandalism from grizzly bears.

In that November of 1984, I was committed to the noble but impossible goal of “no lost data”.  Our small research group had great experience of safely conducting winter research in extreme conditions.  Our field gear was simple but well-tested.  Rather than snow machines (which were soon adopted in subsequent years) we used skis and an ahkio sled to reach field sites.  Ahkio is a Finnish term for an open, canoe-shaped sled. We did not carry tents for emergency survival, but instead small shovels for digging snow caves and to reach our data loggers deep below large snow drifts.  The day length was quite short, so much of our work was completed by headlamp.

In the windswept tundra, the snowpack is quite variable, but almost all features apparent in the summer are gone.  The now common GPS was unknown to most outside of the military and eventually was a heartily welcomed addition to our field equipment, but in those days, we navigated by watch and compass.  We generally knew our velocity.  If we had skied too long and had not found our site, we reversed direction, slightly uphill from our previous track (On skis or snow machines, we always seemed to miss the site on the downhill side.  We always blamed gravity.).

By the time the logger was located, and the shaft dug to the enclosure, much of the brief daylight was gone and the work proceeded by headlamp.  The air temperatures were already very cold, and the winds were picking up.  Upon finally accessing the data logger, I discovered a problem in the programming had only permitted one day of measurements to be recorded before the logger ceased observations.  That brought a very well-learned and well-paid for lesson; the time to learn how to program a data logger is not in the field, at -40°C in a snow pit while the wind blew above the drift.  I put on all my remaining cold weather gear and zipped up my parka until I only had a small tunnel for my field of vision.  And I worked and worked for almost two hours with no break.

I had discovered the problem and was diligently focused upon the repair when an unusual scent floated down the snow shaft, but I was too cold to stop then.   I almost had it resolved, and the scent grew stronger and stronger, but I was too close to be interrupted and could not investigate then.  I was almost done when curiosity finally overwhelmed me, and I tore back my parka hood to look up.  The sight still amazes me to this day.  There on the top of the drift, looking down at me from about four feet away, were four caribou.  And around them were about eight others.  They were certainly curious what I was about and seemed unfazed by the cold and wind.  This was their turf, and I was the intruder.   Although they did not object to my presence, they had to wonder what I was doing, and I certainly wondered myself sometimes.  That was only one of the wonderful memories that I collected working in the Alaskan Arctic.  Those years of struggle and stimulation set the trajectory for the rest of my life and I am forever grateful for the experience.

Dall Sheep

Dall sheep are common in Alaska in mountainous terrain but will not venture into lowland areas, as they require a mix of open alpine ridges, meadows, and steep slopes with extremely rugged “escape terrain” in the immediate vicinity (  Donie Bret-Harte reports that before the pipeline route was chosen, Dave Klein, a foremost University of Alaska wildlife biologist (Klein 2019), made a ski trip from Galbraith through Atigun Gorge and north down the Sag River to Slope Mountain, then across the Slope to the gap between Imnavait Mountain and Slope Mountain before skiing back to Galbraith, passing near Toolik.  This was before the road opened.  His observations of Dall sheep in the Atigun Gorge influenced the state decision that the road should not go through the Atigun Gorge, as had been proposed at one point.

Hobbie and his wife spent a winter in the Brooks Range on a lake in a steep mountain valley.    Dall Sheep were nearly always visible several thousand feet above the lake.  But during the winter the sheep often grazed down at the bottom of the valley during the mid-day twilight, presumably because of the more abundant overwintering vegetation in the valleys than up on the ridges.  The steep temperature inversion in the valley meant that the air at the bottom of the valley was many degrees colder than that at upper levels.  The minimum temperature recorded at the Lake Peters camp was -50.3°C (-58.5°F).


Muskoxen are native to the North Slope but were killed off by hunters between 1890 and 1920 (see Huryn and Hobbie (2012) for the details of the 1979 re-introduction of animals originally from Greenland).  Since their reintroduction in 1979 from the Greenland population (Huryn and Hobbie 2012), they are occasionally seen in small groups along the Kuparuk River where they stay year-round.  They are largely restricted to the Coastal Plain of the North Slope, although one lone male lived in Atigun Gorge in Summer 2018 and another, nicknamed Herman the Hermit, has lived in the Dietrich Valley (on the southern side of the Brooks Range?) for about 6 years, according to Knut Kielland.

The largest males are 135 cm high at the shoulder and weigh 400 kg. Hobbie reports seeing two males fighting (butting heads) along the Dalton Highway in the foothills and Donie Bret-Harte reports: We have seen a lot near Sagwon.


Gus Shaver had a summer research assistant (RA) with a remarkable skill.  She could throw a double-bladed axe.  In fact, she won First Prize in the Axe-Throwing Competition at the Alaska State Fair!  Everyone was very nice to her at camp.

The Lakes group had an aspiring filmmaker for an RA in 2007. Coopting some of the other RA’s and graduate students as cast, he made several short films, including the James Bond spoof “Secret Reagent Man.” This film, sadly, will remain secret, as no copy seems to have survived.

In 2008, two RAs, Ben Abbott and Will Longo, got into a heated debate with two graduate students, Cody Johnson and Ken Fortino, about the best way to inflate a raft. After much “Smack Talk” a challenge was issued, and a competition of who could inflate a raft the fastest ensued. It became quite the event with most of the camp turning out to cheer on the competitors. The RAs Amy Strohm and Max Wilson also entered the fray, with Amy trying to inflate a raft with a syringe and Max with just his mouth.  Neither succeeded while Max nearly passed out.

Rich Flanders was a camp manager who fed the siksiks (arctic ground squirrels) and ravens.  The birds were annoyingly noisy early in the morning and the ground squirrels got very fat.  Rich was a pilot and at times had a single-engine plane that he kept at Toolik and flew now and then.

In the 1950s, Jerry Brown and John Hobbie were graduate students on the North Slope (Jerry was a soil scientist and John a limnologist).  One summer day, when John was sampling Lake Schrader, a hiker appeared along the shore near a small shack set up in the 1950s by DEW Line personnel (this was the Distant Early Warning network of radar stations along the Arctic Ocean).  Workers flew to Lake Schrader for recreational fishing.  The hiker had walked some 60 miles south from the Arctic Ocean and the town of Kaktovak and was well-armed for protection.  While John and the hiker talked, they suddenly saw what they thought was a grizzly bear along the shore about a mile away.   By aiming the rifle scope, they discovered it was the back and bottom of Jerry Brown who was busy digging a soil pit.  See is external).

Ed Rastetter:  His first trip up, Hobbie assured him that we never had lightning at Toolik (is this no longer true?  Is the weather changing?).

Bridge Washouts.

Gus Shaver and Anne Giblin were stranded on the wrong side of the Kuparuk River when the bridge washed out.  They had to spend the night at the Sag DOT camp.  They got back to camp the next day via an improvised ladder-bridge arrangement, but their truck did not get back to Toolik for 2 or 3 more days.  The early bridges were not well-designed, and designers may well have not realized that permafrost landscapes did not absorb much rainfall – a greater percentage of rainfall immediately ran into streams than occurred in non-permafrost landscapes.

Driving on the Dalton Highway

Gus Shaver was in a pickup truck that drove off the highway and rolled over (no injuries).  Another time he was the leader of a group of students staying at TFS and drove them over to Imnavait Creek.  On their return trip, just after they reached the high point on the highway and had the view of Toolik Lake, they saw a small car rolled over at the highway edge and a man’s body in the middle of the road.  They reported this back at camp and an Alaska State Trooper started to drive north to the accident scene.  The law in Alaska is that a victim cannot be moved until a Trooper arrives so there ensued a many-hour traffic stop on the Dalton Highway.  The man had not been wearing a seatbelt, but his wife was and survived without injury.

Laura Gough and students:  Had pulled over to the extreme edge of the road to park their truck.  When they returned from making their measurements and tried to leave, they were unable to get traction on the soft mud and gravel at the edge of the road.  A station wagon with Alaska plates stopped and used its attached power winch to pull them out.   Laura was surprised that a station wagon had such a thing.

Another Laura story was about getting the truck stuck in mud alongside the highway.  Several times.  Each time when they tried to flag-down a large truck it refused to stop.  They only had helpful stops when one of their assistants, an attractive woman, stood next to the road and waved at cars and small trucks.

10.  Terrestrial Ecology

Figures - Terrestrial Ecology


The beginnings of understanding the Arctic as an ecosystem really began in the early 1970’s with the funding of a large research project in Europe and North America, the International Biological Program (IBP).  A part of the U.S. project was aimed at the tundra biome; research was carried out for three summers at the very modern Naval Arctic Research Laboratory at Barrow, Alaska, and synthesized in three books, one on ponds, two on tundra.  These are described in Chapter 5 of this book: Toolik Field Station: Exploring an Arctic Wilderness.  These IBP books were the first reasonably complete descriptions of the tundra biome and of a small arctic pond’s biogeochemical cycles and trophic interactions.

The IBP results from the 1970’s showed that the important limiting factors in tundra biogeochemistry were slow inputs and turnover of elements other than C, particularly N and P (Shaver et al. 2014).   Since then, research largely carried out at the Toolik Field Station has indicated that arctic species are well adapted to the cold environment.  The primary limitation and regulation of long-term response to temperature over decades is the slow input and turnover of elements like N and P.  In addition, it has been discovered by observations that interactions among species in plant communities are important and that the composition of species of tundra ecosystems have had a major impact on biogeochemistry and vegetation.   All told, species effects and the slow change in element cycles make the tundra ecosystem much more resistant and resilient to climate warming than was expected.   Very careful and exacting observations of plant species and their growth over 30 years, however, has revealed relative increases in the abundance of shrubs and vascular plants vs. bryophytes (mainly mosses).

Present Climate at Toolik Lake.

The present climate at Toolik Lake (Fig. 10.1) is low-arctic with a mean July temperature of 10-12oC; the average annual temperature is ‑8oC.  Summer (June, July, August) average temperatures may climb above 10oC while the winter average is ‑20oC.  Persistent snow cover begins in late September and lasts until late May.  The maximum snow depth is around 30 cm, but drifts form behind every obstruction and in every hollow.  The sun is above the horizon continuously for more than two months during summer and below the horizon for two months in winter.  The 3-month total rainfall for June, July, August averages 188 mm, while total annual precipitation is 250-350 mm (Cherry et al. 2014).  Plant photosynthesis begins as soon as snow melts in late May, but by this time nearly half of the total solar radiation is past (Fig. 10.1).

The low annual temperature means that permafrost is present down to about 200 m depth.  The minimum temperature at depth in the Toolik Lake region is close to -4oC and is getting warmer (see Fig. 9.3) permafrost temperatures along the Dalton Highway are warming near Toolik at about 0.05oC per yr).  The depth of the annually thawed layer, called the active layer, varies from ~30 cm to 1-2 m depending on topographic position, soil moisture and surface water flow paths, thickness of the overlying organic and litter layers, and the structure and density of the vegetation canopy.  Soils are all formed over permafrost; they are cold, wet, and with high organic content.  Parent material is fine-grained loess (wind-blown sediment) and glacial deposits.  The age of the glacial deposits is given in the legend of Table 10.1.

Different Ages and Makeup of Vegetation on Soils Near Toolik

Soils near Toolik have developed on glacial till, the unsorted sediment directly deposited by a glacier. The oldest soils (Sagavanirktok) developed on glacial till >300,000 yr BP (before present), the next oldest (Itkillik I) on till from 60,000 yr BP, and the youngest (Itkillik II) on till from 10,000 yr BP.  Topography interacts with soil over time to produce four dominant terrestrial ecosystems:  moist acidic tundra, moist non-acidic tundra, heath, and wet sedge.  Most of the LTER site (60%) is covered with moist acidic tussock tundra (Fig. 10.2).  Here, a number of shrubs (willow, dwarf birch) and herbaceous flowering plants are always present but the tussock-forming sedge (Eriophorum vaginatum) dominates

There is an obvious difference between the present-day vegetations that are growing on the oldest soils and those on the youngest soils (Fig. 10.3).  The vegetation on the Sagavanirktok soil, the oldest, is continuous tussock tundra that completely covers every part of the smooth hills.   In contrast, the surface of the Itkillik II age soil, the youngest, is rocky with discontinuous vegetation.  Slopes are often steep and irregular.  Kettle lakes with irregular shorelines are common.  The makeup of the vegetation also differs in the three ages of soil (Table 10.1).   In the oldest landscape (Sagavanirktok), tussock sedge is clearly dominant.  In the youngest soil, the non-tussock sedge is dominant.   Also, by the time of the Itkillik-age soils, the dwarf-shrub and the non-tussock sedge becomes more abundant.   Finally, the low-to-tall shrublands are present only in the two Itkillik-age soils and in riparian zones or in “water tracks” with greater subsurface water flow (Chapin et al. 1988

There are also consistent changes in the vegetation along river terraces (Fig. 10.4).   For example, there is a change in elevation of 5-7 m from top to bottom of the river terraces along the Sagavanirktok River.   In this location, the tundra vegetation changes drastically with dry tussock tundra at the top, wet sedge tundra in wetter locations, and willows found near flowing water.

Plant Species Diversity Near Toolik

The diversity of plants in arctic tundra (L. Gough Vignette in Shaver et al. 2014) is limited mainly by the low temperatures and short growing season.  There are no trees and even annual plants are rare.  Most of the seed plants are long-lived perennials that reproduce vegetatively, not sexually (e.g., by bulbs, tubers, runners, etc.).  The grass-like species survive the winter underground by storing large resources in belowground stems and roots.  Dwarf shrubs maintain their woody biomass aboveground and need snow cover to protect them from wind and frost damage during the winter.  Broad-leaved herbs also occur and produce flowers.  These can reproduce sexually but recruitment from seed is rare.  Mosses are an important part of many tundra communities.  For example, Sphagnum mosses build up acidic conditions while producing peat and organic matter.  Lichens, made up of a fungus and a photosynthetic organism (an alga or a cyanobacterium), are also important and are often a valuable food for mammals, such as overwintering caribou.

Consumers and Decomposers

The most abundant herbivores are two small voles, the tundra vole and the singing vole, whose main foods are sedges and some herbaceous dicots (nonwoody flowering plants such as legumes, buttercups, and sunflowers).  Batzli and Hentonnen (1980) (quoted in Shaver et al. 2014) suggest that at Toolik the abundance of these animals may be inversely correlated with numbers of foxes and weasels, as was true for lemmings in coastal Alaska.  For the North Slope, an estimate of the number of voles and their main predator, the red fox, is 1 fox and 50,000 voles per 10 km2 (Huryn and Hobbie 2012).  Another mammal seen in the Toolik region is the arctic ground squirrel which locates its burrows in relatively dry soils that are deeply thawed.  The predators on the small mammals include jaegers and other birds of prey, foxes, and wolves.  Caribou are a food source for wolves and grizzly bears.  While caribou of the central arctic herd are found in small groups in the Toolik region, it is not a calving ground; they are not major foragers (Lenhart 2002) but herds do appear every 5-8 years at the end of summer.

The herbivores at Toolik Lake—mammals, birds, and insects—consume live and dead plants and also drastically affect plants through burrowing and trampling and through redistributing elements in their waste.  However, the overall consumption by herbivores is relatively small compared with that in temperate ecosystems as less than 5-10% of annual aboveground production is eaten.   The question remains, does the relatively small consumption affect the plant communities?  This was answered by a ten-year experiment (Johnson 2008) that kept several areas of the moist acidic tundra (MAT) and the dry heath tundra free from any herbivorous mammals.   In the experiment, small mammals had small but significant effects on community structure, primary productivity, and biomass.  For example, the sedge that forms tussocks in MAT did not recover well from vole damage to tussocks even under increased nutrients.  However, under the same conditions of nutrients and voles, tundra birches showed greater growth.  In dry heath tundra, herbivory greatly increased the fertilizer-induced dominance of the grass Heirochloe alpina.

Certainly, the whole terrestrial food web is affected by the year-to-year variability in snowmelt and the timing of vegetation changes.  For example, several earlier studies at Barrow showed that the interannual variability in weather and plant growth controls the abundance and timing of insects and spiders (Pitelka 1973).   At Toolik, preliminary data from J. Wingfield (personal communication in Shaver et al. 2014), show clear correlation between arthropod abundance and weather.  For example, a year with cold spring temperatures resulted in later emergence and fewer flying insects than a normal year.

The breeding success of arctic birds depends on the terrestrial food web and upon adequate time for breeding and raising young.  The arrival time of songbirds in the Arctic is set by photoperiod and, therefore, is similar every year.   Breeding success, however, varies from year to year and is quite dependent on the timing of the spring snowmelt.  Lapland longspurs at Toolik Lake, for example, have a successful early season breeding activity in years with early spring snowmelt; this activity relates to the frequency of the male call, songs, and flight frequency.

The decomposer organisms, including bacteria, fungi, and others, are the most abundant consumer organisms in the soil.  These soil organisms are responsible for most of the heterotrophic respiration (RH) and for most of the recycling of N and P and other essential nutrients in plant litter into forms that can be reused by plants.  These soil organisms also contain in their bodies a great deal of labile forms of essential elements.   For example, in similar measurements at Toolik Lake of moist acidic tundra and wet sedge and at Abisko, Sweden, of heath tundra, Schmidt et al. (2002) found that the amount of labile N and P in microbes equaled or exceeded the amount in the vegetation.

The Importance of the Active Layer

In tundra ecosystems, soils rather than whole plants contain by far the largest pools of organic matter and essential elements such as C, N, and P.  Near Toolik Lake, soils typically have an organic (O) horizon (the peat layer) of varying thickness (Fig. 10.4) overlying a silty mineral soil.  The peat layer is made of partially decomposed plant material with very little mineral content, while the lower, mostly mineral soil also contains significant organic matter and mineral elements.  The thickness of the active layer (the annually thawed layer of soil, usually including the peat layer and the upper mineral soil) is a critical determinant of the volume of soil in which C and other elements cycle.  It is also true that in most tundra soils, there also may be large amounts of organic matter and element stocks below the active layer; these, however, reflect former conditions with a deeper annual soil thaw and are not cycling.

Both the thickness of the O horizon and the thickness of the active layer are highly variable and reflect the effects of topography, soil drainage, heat transfer within the peat, and effects of plant litter and plant canopy on heat flux into the soil.  Near Toolik Lake the parent material is generally glacial till, outwash, or morainal material of various ages.  The pH of the younger soils is close to neutral or slightly acid (>5.5), while the pH on older surfaces Is often 3.5-4.5 or acidic.   The rate of decomposition depends on soil moisture and temperature, so the presence of permafrost is a key factor.   Amazingly, microbial activity may continue even as soil temperatures descend below -5oC to -10oC in the late fall.

Inputs, Outputs, Turnover, and Budgets of Carbon and Nitrogen in Tundra

Fig. 10.5 shows the amounts of carbon (black) and nitrogen (grey) in the moist acidic tundra near Toolik Lake.  The amounts in various pools are given in boxes (g m-2) and arrows indicate important fluxes per year (g m-2 y-1).  The RH is respiration by microbes and RA respiration by photosynthetic plants.  The GPP (gross primary production) is photosynthesis.

The amount of carbon and its location in an ecosystem is shown in the labeled boxes in Fig. 10.5.  Most of the carbon, 8700 g m-2, is Soil Organic Matter (SOM).  It is added to each year from photosynthesis (GPP 300 g m-2) by way of vegetation which turns into litter and then enters SOM.   It has to be remembered that organic matter formation begins with GPP and the organic matter is broken down by invertebrates and microbes, releasing C as RH and RA.  Respiration by vegetation and by soil microbes releases roughly equal amounts of carbon back to the atmosphere.  It was surprising to find out that soil respiration occurring in the four months of September through December could account for 20% of the total respiration.  This takes place because in the soil, films of liquid water remain on particles down to as low as -10oC, allowing microbial physiology to continue.

It was obvious that there were many rapid changes occurring in the net ecosystem exchange (NEE), the balance of incoming GPP and outgoing RH plus RA.   Euskirchen et al. (2012) set out to measure the NEE using the newly developed “eddy covariance” method for continuous measurement of CO2. They set up “flux towers” at Imnavait Creek (near Toolik Lake), in three different tundra vegetation types: heath tundra, tussock tundra, and wet sedge tundra, and recorded from them continuously for three years.   In one example of their results, the midsummer NEE of tundra, integrated over a full day, showed a net C gain of 0.5-1.5 g C m-2 d-1.  Over the three summer months when GPP exceeds the sum of RH plus RA on most days, it was found that cumulative NEE at Imnavait Creek varied from 51 to 95 g C m-2 d-1. Therefore, during the growing season the tundra is a net sink for carbon. The timing of the important switch of the tundra from net source to net sink appears to be a function of the number of growing degree days early in the season, indicating that warmer springs may promote increased net CO2 uptake. However, this increased uptake in the spring may be lost through warmer temperatures in the late growing season that promote respiration. It may happen, however, that this respiration is impeded by heavy precipitation or cooler temperatures.

Thus, there are now sufficient data to answer the fundamental question: annually, is C being added to or lost from the tundra?  Euskirchen et al. (2012) concluded that “Net CO2 accumulation during the growing season was generally lost through respiration during the snow-covered months of September–May, turning the ecosystems into net sources of CO2 over the measurement period.”

While the flux towers give observations on the current losses of C from the tundra soils, there is still the question about the source of the large amounts of organic carbon in present soils (e.g., Fig. 10.5).  G.R. Shaver, in a personal communication, said “the reason we have so much organic matter in total is that it has been accumulating at least since the last glaciation.  There may be periods decades to centuries long where NEE is positive, negative, or near zero.  Under the current climate, there may be a net loss of C in at least the wet sedge ecosystems, as shown by Euskirchen et al.  near Toolik.”

The nitrogen story (Fig. 10.5) is not at all similar to that of carbon (Shaver et al. 2014).   First, the quantity of N that enters the tundra system from outside the ecosystem, that is, through measured N fixation and deposition from the atmosphere every year, is only 0.1–0.2 g N m2.   Second, the quantity of N needed to construct plant material every year is a relatively large 0.4 to 4.5 g N m2.  Third, the amount coming in is so small that the necessary N has to come from direct recycling of the N already in the ecosystem.  This recycling occurs when the soil organic N is mineralized to ammonium or nitrate, followed by plant uptake.  Fourth, there are important modifications of this uptake when fungal mycorrhizae take up inorganic N and transport it into plants (Hobbie and Hobbie 2006) or when plants directly take up organic N (Kielland 1994; Schimel and Chapin 1996).  In the soil near Toolik Lake, Hobbie and Hobbie (2006) found that around 50% of the uptake of N into all plants takes place through fungal mycorrhizae.  Using a slightly different method, Yano et al. (2010) estimated that 30-60% of the plant nitrogen came from fungi.  This uptake via mycorrhizae was true of many plants including dominant shrubs such as Betula nana.

The other side of the nitrogen story is about the main losses of N from tundra ecosystems (Shaver et al. 2014).   These losses are first by leaching from plants, litter, and organic particles as dissolved organic and inorganic N.  Next, the losses from the amounts of leached N leaving tundra watersheds in stream flow are 50-100 mg N m2 yr1 (Peterson et al. 1992).  These are very close to the 100 to 200 mg N inputs mentioned in Shaver et al. (2014) as fixation and deposition for a typical year.

Shaver et al. (2014) summarized the N and C cycles well: “the external inputs and outputs of N (fixation, deposition, denitrification, and leaching losses) are all small relative to the internal exchanges of N among organic matter pools (plant uptake, litter fall, mineralization).  In other words, the N cycle is relatively closed and depends strongly on internal recycling of N.”

“In contrast to the situation for N, the external inputs and outputs of C (GPP, RA, RH, leaching losses) are mostly large relative to internal exchanges of C (litterfall, plant uptake of organic molecules, consumption by microbes, leaching losses, and herbivores); in other words, the C cycle is relatively open in comparison with the N cycle.”

Environmental Controls of Productivity: Temperature, Light, and Fertilizer

The effects of changes in temperature, light, soil moisture, snow cover, and length of growing season have all been tested in both short- and long-term experiments near Toolik Lake (Shaver et al. 2014).  These studies showed that the productivity of these systems is mainly limited by the availability of N or N + P to plants.  These experiments took place in Itkillik I soil (Fig. 10.2) at the top of the hill lying immediately south and west of Toolik Lake; the experiments were carried out on rectangular plots with and without treatments of greenhouses (Fig. 10.6) that held added heat, greenhouses with added fertilizer, mesh-covered plots with 50% light, and plots with added fertilizer.

The results from experiments at Toolik Lake (Fig. 10.7) on effects of nutrients, light, and temperature on growth of tundra plants are consistent with experiments throughout the Arctic.  That is, the growth responds more to changes in nutrient availability than to changes of temperature or light.  When N and P response have been separately tested (Shaver and Chapin 1995), the response to N usually dominates.  In wetter sites, there appears to be greater importance of P limitation, which is probably related to the chemical immobility of P at the low pH and low soil oxygen status characteristic of these wetter sites (Shaver et al. 2014).

At Toolik Lake, there can be drastic changes over time.  In moist acidic tundra, grasses and sedges often dominate in fertilized plots in the first 1-6 years of treatments and may retain their dominance for the next 6-20 years as long as the dwarf birch Betula nana is absent (Bret-Harte et al. 2008).  However, when Betula nana is present, there can be a dramatic increase in the size and abundance of this rapidly growing shrub so that it takes over and eliminates most other plants (Shaver et al. 2001).   The pictures of the greenhouses already described in Fig. 10.6 show two heights of the greenhouses.  The one on the right does not contain fertilized plants and so is close to the original height of the greenhouses when they were first established, with walls that were perhaps 40 cm high.  The greenhouse on the left has been fertilized every year so plants kept growing and the greenhouses had to become larger as well.  The walls of the greenhouse on the left are close to 120 cm high and they eventually became 2 m high, mostly because of the growth of B. nana.

Fertilization Effects on C and N Aboveground and Belowground

In one of the experiments shown in Fig. 10.7 (called T81), ecologists also measured changes of C and N in plots that received a yearly fertilization with 10 g m-2 N + 5 g m-2 P from 1981 to 2000.   Thus, the plots received a total of 200 g m-2 N and 100 g P m-2 over a period of 20 years.  As illustrated in Fig. 10.8, the results are the size of the aboveground and belowground pools of C and N.   Aboveground pools included shoots, rhizomes and standing dead plants.  Belowground pools included surface litter, roots, and soil (organic and mineral).  The surprising results were that the total recovered was only a small proportion of the amounts added.

As stated in Mack et al. (2004) “the total amount of N in fertilized plots was, if anything, less than the amount in control plots.  If all of the added N had remained on the fertilized plots the total amount should have been at least 50% greater.  All of the losses of N were from (a) mineral soils and (b) portions of the organic mat below 10 cm.“  It is likely that much of the N was lost from N in older organic matter that was mineralized and then lost.  The net losses of N in fertilized plots were matched by a similar pattern of net C loss, also entirely from belowground pools, despite a doubling of productivity (seen in the doubling of C in aboveground pools).   This result Indicates that the C lost was old-soil organic C and not recently fixed C or surface litter C.   The large losses of deep, probably older soil organic matter after 20 years of fertilization support the idea that soil decomposition processes, along with primary production, are N-limited in this tundra (Schimel and Weintraub 2002).

Natural Climate Change Effects on Cotton Grass Flowering and Complete Vegetation

With the exceptions of fire or permafrost thaw, change at the ecosystem level takes time because many linked processes are at work and these do not all change at the same rate (Shaver et al. 2000).   Therefore, neither annual production nor biomass of the tundra at Toolik Lake are well correlated with weather variables such as temperature and solar radiation.   There is one natural process that has received a detailed study from 1980 to 2011, the strength of the annual flowering of Eriophorum vaginatum (cotton grass).  This flowering was studied both at Toolik Lake and also along a 300-km transect from the Yukon River to the northern coastal plain, namely the Dalton Highway (Shaver et al. 1986).   This flowering varies more than 100-fold from year-to-year, and it was unexpected to discover that the Toolik Lake results closely correlated with the Dalton Highway results (Shaver et al. 2014).  However, the flowering results were not correlated with the annual variation in weather.  This 2014 publication states “the most likely explanation for this observation is that flowering is a process that is controlled over several years of weather and plant response.  Only after 30 years of observation is it becoming clear that years of high flowering appeared after at least two warm summers with good growing conditions and favorable conditions for soil N mineralization and N uptake by plants (J. Laundre unpublished; LTER database).”   Thus, in order to have a strong flowering year it appears necessary to have favorable climate for several years, which then affect the soil processes and plant uptake processes.

There will also be small effects of a changing climate on the tundra vegetation as a whole.  But measurements of small changes over time require methods that can measure the presence and size of the canopy of individual plants, and then remeasure the same precise sites at yearly intervals.  The method developed by Walker er al. (1989) and described by Mercado-Diaz (2011) makes use of two large grids, one at Toolik Lake and one at Imnavait Creek.  Monitoring within these large areas was carried out at a total of 155 small permanently marked plots.  At measurement time, an aluminum frame with a paired grid of wires was placed above the vegetation and aligned with the permanent markers at each small plot.  The same points were re-sampled for many years by sighting downward and aligning the paired crosshairs.  This method makes sure that a view of the vegetation from above the grid is of exactly the same point.  Each successful view of vegetation above a sample point is called a hit.

The 20-year record (see W.A. Gould and J.A. Mercado-Diaz Vignette 5.5 in Shaver et al. (2014)) from these two large grids indicates a general increase in vascular plants (Fig. 10.9) of 18.6% whereas nonvascular plants decreased: the decrease for lichens was 9.3 %, for non-Sphagnum mosses was 20%, and for Sphagnum was 28%.  In contrast, the increase for graminoids (grass-like plants) was 25.5%, for herbaceous dicots (small non-grass flowering plants) 24%, and shrubs 13%.  Canopy height plus its horizontal extent increased over time.

Effects of Climate Changes on Permafrost, Wildfire, and Carbon Balance

Permafrost is now an important feature of arctic Alaska; however, the prediction is that between now and 2100 a considerable portion of the permafrost in the Arctic will thaw (Schuur et al. 2011).  When permafrost thaws and the contained ice melts, the land surface may subside and form thermokarst terrain.  Then an event such as a large rainfall may cause a slump or large movement of soil and tundra downhill (see Chapter 11, Stream Ecology).  One such slide, about 800 m long, was pictured in Bowden et al. 2014.

Another natural process that destroys arctic tundra is wildfire.  Small wildfires instigated by lightning do occur on the North Slope but in 2007 there occurred an extraordinarily large fire 23 km northwest of Toolik Lake.  This was a rare event for the North Slope and, in fact, a study of lake sediment cores from the edge of the 2007 fire (Hu 2010), showed recent fire evidence at the top of the cores but no evidence of any other fires for the past 5,000 years.  This 2007 fire (see Fig. 9.19, Fig. 9.20, and Fig. 9.20 for photos) lasted for three months and covered 1,039 square kilometers near the Anaktuvuk River (described in detail in Mack et al. 2011).   It was the largest fire on record for the worldwide tundra biome.   The fire moved approximately 2.1 teragrams (1012 g) of carbon to the atmosphere, an amount similar in magnitude to the average annual net C sink for the entire Arctic tundra biome.  It is very likely that a warming climate will lead to more wildfires, to more C lost from the tundra, and an amplification of climate warming.

Beyond the direct effect of combusting organic material to CO2, wildfire also has the potential to change ecosystem structure by changing the reflectance and energy balance of landscapes underlain by permafrost.  The major effect is through the removal of the soil organic layer that insulates permafrost from warm summer temperatures.  This disruption leads to permafrost thaw and destabilization of the ground surface.

11.  Stream Ecology

Figures - Stream Ecology

Tundra Streams

The streams near Toolik Field Station, where most of the stream research has been carried out, are tundra streams.  These are the most abundant type of stream on the North Slope, making up 82% of the total stream length (Bowden et al. 2014).   The tundra streams near Toolik originate in the foothills lying north of the Brooks Range (Fig. 9.1); they then enter the Kuparuk River (Fig. 11.1) which flows north through the foothills, across the coastal plain, and into the ocean (Fig. 1.3).   Figure 11.2 shows the location of Toolik Lake and the nearby rivers flowing north just east of the Dalton Highway.   The overall location of the foothills is shown in Fig. 9.1.

The source of water in tundra streams is snowmelt and precipitation.   A typical catchment is made of a relatively thin layer of peat, 25-30 cm deep, underlain by impermeable permafrost hundreds of meters thick.   In some places, tundra streams drain a region with permafrost that is particularly rich with ice.  In these regions the channel often has a beaded form; this means that a series of pools have formed, each around 10 m in width (beads) that are connected by relatively short connector reaches.  These pools, often 1-2 m deep, form from melting of ice wedges or ice accumulations in the permafrost.  The series of pools often form along the borders of permafrost polygons.  In the region near Toolik Lake, much of the drainage basins away from the river proper are rocky soil with little or no peat.

Rate of Stream Discharge and Stream Chemistry

In a small headwater catchment of a tundra stream, the water may reach a flow of 8-10 m3/s after a summer rainstorm but diminishes within a few days as there is little water storage in the watershed. This “flashy” pattern of fast rise and flow can be seen in the overall discharge of the Kuparuk (Fig. 11.3).   These tundra streams flow in the summer from sometime in May until sometime in September with a normal flow of 1-5 m3/sec.  They are frozen solid from October until early May.   Peak flows early in the year can deliver up to 25% of the total yearly flow.  However, the largest measured flow events, at nearly 100 m3/sec, occurred in July 1999 and August 2002.  In contrast, drought prevailed in parts of summer 1990, 2005, 2007, 2009, and 2011 during which times there was no surface water flowing in some reaches of the upper Kuparuk River (Bowden et al. 2014).  However, even at the time of overall drought there are some river sections with a minimum flow of 0.2 m2/sec always present.  One such section lies just upstream of the Dalton Highway crossing where its flow is maintained by underground water flowpaths.

Dissolved nutrients in the tundra streams are very low in concentration and are held low by the growth of stream algae.  These compounds include total dissolved phosphorous, nitrate, and organic forms of carbon, phosphorous, and nitrogen (Bowden et al. 2014).  The major source of dissolved organic carbon is seepage from tundra and runoff from the surface.  The dominant source of particulate organic carbon, in contrast, is from erosion of peat in the eroding shore of streams.  A second source is leaves and twigs from stream-side willow and birch plants.  A third source is the somewhat rare aquatic mosses as well as biofilms growing within the stream.   Breakdown rates of terrestrial leaves that are resistant to decay are driven by the initial colonization of leaf tissues by aquatic fungi.  After colonization by fungi, the detritus is then consumed by macroinvertebrates, especially insect larvae.

Stream Food Web: Algae, Insect Larvae

The algal communities of the stream are all attached and growing on cobbles or larger rocks.  These cobbles have a size of 6 to 26 cm, larger than a pebble and smaller than a grapefruit (Fig. 11.4)The abundant moss growing on the rocks in the right-hand picture occurred years after the fertilization experiment started (Bowden et al. 2014).   Cobbles in the unfertilized Kuparuk River are shown in this figure (left hand side) and were covered with a biofilm of tiny algal cells dominated by hundreds of species of diatoms; an important feeder on diatoms is the larvae of the black flies (Prosimulium) that construct nets to capture detached diatoms from the flowing water (Fig. 11.5).  Diatoms are a major source of food for other immature insects too.  In one case, that of the midge larva the chironomid Orthocladius, the insect larva builds a 3 cm-long silken tube and feeds exclusively on diatoms that grow on this tube.   The caddisfly larva Brachycentrus is both a grazer and a filter feeder.  It builds a portable case from stones and plant fragments.  Baetis, a mayfly larva, grazes algae and decomposing organic matter.  There are also immature insects that are predators on other stream insectsSimilar insects and processes are found throughout Alaska.

Stream Food Web: Life History of Grayling

In the 200 km of the upper Kuparuk River (Fig. 11.2), arctic grayling (Fig. 11.6) are the only fish species.  They spawn in streams where there are spawning beds made from material as fine as sand or as coarse as gravel.  As adults, grayling may range widely as they move many tens of kilometers each year between spawning, rearing, and sheltering habitats.  At the late summer and early fall freeze-up, the adults in the Kuparuk River near the Dalton Highway return upstream 14 km to Green Cabin Lake (Fig. 11.6) where there is a relatively large population of lake trout.  This fall return of the grayling provides the food the lake trout need to survive overwinter.   When the lake thaws in late May, the remaining grayling re-enter the river, spawn, and move to summer territories that they defend against other grayling.  Tagging over many years and restricting grayling movement with weirs of plastic mesh stretching across streams (Fig. 11.7, Fig. 11.8) has revealed that individual grayling return to the same feeding and spawning areas year after year (Buzby and Deegan 2004).

Another characteristic of the grayling summer life history is that the small grayling, the 1 to 5 years old fish less than 29 cm in length, choose to live exclusively in small streams such as Hershey Creek, a tributary of the Kuparuk.  Adult fish, 6 to 18 years old and 30 to 43 cm in length, use larger rivers such as the Kuparuk River (Fig. 11.8).  In their summer habitats, the small and large fish must consume enough food to grow, migrate to the overwintering lake, survive the long winter, and spawn the following spring.  Their primary food is drifting aquatic insects, mayflies, stoneflies, and caddisflies.  Early in the summer fish rely on midges (Chironomidae).   Less than 20% of their total food comes from terrestrial insects that fall into streams.

The long-term detailed study of the streams and rivers near Toolik Lake (Deegan et al. 1999) revealed an environment that varied greatly from year to year, with some very cold years and some years of severe drought.   How have grayling adapted to the variable arctic environment with these extremes of temperature and water flow?  First, they have evolved a life history that includes a long-life span, annual reproduction, and relatively few offspring per spawning event, thus increasing the chances that some offspring will encounter favorable conditions (Bowden et al. 2014).  Second, the rate of growth of the fish varies with the water velocity and water temperature, and the young of the year (Y-O-Y) and the adults have opposite growth responses.  Adult fish grow fastest and produce the most eggs in moderate to high flow years with cool water, whereas the Y-O-Y grow fastest and survive best in low flow years with warm water.

Phosphorus Experiments: Algae and Moss

Which nutrients limit algae in streams near Toolik?  In the chemical makeup of algae world-wide, the ratio of grams of N to grams of P averages 8 to 1.  In the water of the tundra streams near Toolik Lake, the ratios of total dissolved N to total dissolved P (that is, TDN:TDP weight ratios) have an average of 45 to 1 (Bowden et al. 2014).  This means, based on the needs of stream algae, that these streams are likely phosphorus limited with a surplus of nitrogen relative to dissolved phosphorus.  This conclusion came from prior knowledge of algal chemistry combined with the data on concentration of nutrients in the stream.   To test this idea, a summer-long field measurement (Peterson et al. 1983) was made of algal growth on glass slides suspended in transparent tubes in the river.  River water flowed through the tubes that received additional amounts of continuously added nutrients.

Conclusion 1.  Phosphorous concentrations in the stream are low and limit algal growth.  Additions of phosphate alone or phosphate plus inorganic nitrogen increased chlorophyll and photosynthesis; nitrogen alone gave no stimulation.

What is the effect of added dissolved phosphate on the stream algae?  The next, and major, experiment consisted of a slow drip of phosphoric acid into the flowing water and measurements at weekly intervals of P concentration for 5 km downstream.  This addition raised the average concentration at the addition location by 9 ug/liter at a nominal water flow rate of 2 m3/s.

Conclusion 2.   Algal biomass and production increased by 1.5 to 2-fold in the fertilized section that extended about 4 km down the river.  The measurements (Slavik et al. 2004) were made of algae, mostly tiny diatoms growing on rocks, near Toolik.   The data interpretation was made difficult by changes in stream discharge which caused a 2-fold change in algal mass from year-to-year.  When the flow was very high, scour occurred, and algal biomass was only half as great as at low flow.

In the experiment, the algal chlorophyll responded rapidly even at the start of the addition of P to the stream.   One further question also tested was how long would the chlorophyll continue to survive in the algae after the cessation of the added nutrient?  This was tested when the addition point was suddenly moved downstream.  This movement of the addition point was carried out several times and the return of the algal biomass to the reference levels always occurred within a year.

Are other aquatic plants affected by added dissolved phosphorous?  Mosses are normally rarely found in tundra or mountain streams. One small green, flowerless plant, a moss or Bryophyte, is usually found in only a few naturally enriched parts of these streams.  These rare areas have enriched spring or seep water entering into the stream (Peterson et al. 1986).

Conclusion 3.  After phosphorus addition for many years, mosses came to dominate the riffles of the tundra stream.   The experiment began in 1983 but stream ecologists were completely surprised in 1990 when they realized that a species of moss was becoming important in riffles (Slavik et al. 2004).  Six years later, the biomass and nutrient uptake by the riffle mosses was so great that these organisms had become dominant over 60% of the riffle area (Fig. 11.4).  This moss invasion had a tremendous impact on the physics, biogeochemistry, and biota.  When the moss amount increased, so too did very high amounts of algal growth on the moss fronds.  The biomass of the insects living on the moss fronds, mostly mayflies and chironomids (midge larvae), also increased greatly.

Phosphorus Experiments: Insect Food Web and Response of Grayling

In order to determine the food web relationships, Peterson et al. (1993) measured the fertilization-caused enhancement of the naturally occurring stable isotope 13C in insects and grayling to determine connections between organisms in the stream food web (Fig. 11.9).  The figure shows values from a control section that lies upstream of the point of fertilization and the values from the fertilized section lying downstream from that point.   The shifts in the delta 13C values of consumers are due to change in algal delta 13C values caused by P addition.  The delta 13C values of carbon inputs from the watershed are not changed by the P addition.

The web begins with the value of -29 delta13C in the epilithon, that is, in the matrix of detrital carbon and diatoms on the rocks.   When this epilithon becomes detached, the particles are captured by insect larvae that use nets to filter (e.g., the black fly larvae Prosimulium (Fig. 11.5)).  The chironomid larva Orthocladius relies upon feeding on diatoms living on the 3.6 cm long silk tube in which the larva lives.  Each tube is attached at one end to a riffle rock.  Baetis also grazes upon the epilithon but its food is in the film covering the rocks.  The low delta13C value for Baetis in the control reach indicates that it selects the algal component of the epilithic biofilm.  Brachycentrus (a caddisfly) is both a grazer and a filter feeder.  It is notable that the delta13C value of Orthocladius is very strongly enhanced by fertilization, suggesting that the diatoms feeding the Orthocladius have been strongly stimulated in their carbon uptake.    Another interesting result is that the Y-0-Y grayling changed their isotope value more than the 7–10-year-old adults.  This is to be expected because of the longer time needed for equilibration of the 13C concentration in the new food with the large muscle mass of the adults than with that of the very small young fish.

The weights of individual Y-O-Y grayling and adult grayling in the control and fertilized reaches were measured in summer 1986 at two sites (fish weirs) upstream and two sites downstream of the phosphorus dripper in the Kuparuk River.   The sampling period was 3-5 weeks after the fertilization began (Fig. 11.10).   In this figure, numbers along the abscissa are the kilometers above and below the dripper sites.

The great increases in the insect biomass in the fertilized stream resulted in a large increase, some 40%, in the weight of the individual Y-O-Y grayling sampled in the fertilized reaches compared to those in the control (Fig. 11.10)Similarly, adult grayling growth in summer 1986 was twice as great in the fertilized reach as in the control reach (20.6% mass gain in fertilized vs. 8.9% in the control).   These increases are important for the overwinter survival of Y-O-Y grayling and adults as well as for the successful reproduction of adults the next spring.

Climate Warming: Response of Grayling

There is evidence from the Toolik region, described earlier in Chapter 9 and later in this chapter, that there is a slight warming being measured every year at a depth of 20 m in the permafrost.  At this time, however, the temperature changes in the air are too variable and have not yet been collected for long enough to draw similar conclusions about the long-term air temperatures.  But the measured changes do agree in general with the 110-year record being recorded at Barrow and other data published by ACIA (2004); Cherry et al. (2014) conclude that at the Toolik site it is very likely that there is both climatic warming and an increase in precipitation occurring.

Grayling are a migratory species and are therefore susceptible to environmental changes that affect either their summer or winter habitats. One major ongoing change is warming of water during midsummer feeding in streams.  At this time, the Y-O-Y do better when the temperature is warmer while the adult fish could become stressed during a very warm midsummer period.  A second major change is an increasing frequency and seriousness of droughts in the Kuparuk River drainage, as seen in long-term measurements of the discharge volume at the mouth of the Kuparuk near Prudhoe Bay. These measurements show that the runoff total quality has not changed but there has been an increase in the total length of annual runoff time, i.e., the same amount of water is spread over more time (Cherry et al. 2014). From the grayling’s point of view, there has been a decrease in habitable areas and a probable barrier to summer migration, particularly the annual late-season upstream movement to overwintering habitat in Green Cabin Lake that occurs during August. Thus, the higher variability in discharge conditions including drought may stress the fish populations.  Grayling in streams near Toolik survive under highly stressful and variable conditions at present, but only because one or several years of bad conditions that reduce reproductive success do not eliminate populations of this long-lived species.

A third major change is increased runoff from melting permafrost. This runoff contains high concentrations of phosphorus, ammonium, and particles of soil; all this material can enter streams and will affect hatching of fish eggs, as well as young graying growth and development to adults.  Bowden et al. (2014, p. 229) summarize ecological projections on fish and says “Based on our observations in the Kuparuk River and nearby streams, the rapid climate changes that are projected to occur in the Arctic pose a serious threat to the survival of arctic grayling in the area.  It takes an interconnected and varied landscape including clear, cold rivers, streams, and lakes to sustain a grayling population.”

Climate Warming: Effects on Soil and Streams

The long-term changes in the Toolik climate are described in Chapter 9.  Luckily, there is a long-term temperature measurement ongoing in an 80 m deep borehole at nearby Galbraith Lake; the best depth for measuring a long-term annual temperature is at 20 m where summer and winter differences converge (See Fig. 9.3).  At this depth, the temperature is now about -5oC but there has been a warming of 1oC over the past 20 yr.  At this rate, permafrost (permanently frozen ground) will be widely disappearing over the next century.

Permafrost refers to land that remains frozen over the annual cycle, regardless of the presence of water. Nevertheless, permafrost layers can, and often do, contain ice in various forms.  It can be found as massive ice chunks, in microscopic pores in the soil, and as lenses of segregated ice of various sizes (Fig. 11.11).   When such different types of ice melt, the land surface often subsides and dips and even drainage channels in hilly country can form.   The irregular land surfaces that result from this process are called “Thermokarst Terrain”.  Once this type of terrain forms, events such as a large rainfall or a very warm summer may cause massive soil slumps along stream valleys or on lake shores.   One example of a massive soil slump on a lake shore is pictured in Fig. 3.29; this slump occurred on the shore of Lake Schrader at the end of the very warm summer of 1958.   Another example of a hillslope failure in Thermokarst Terrain happened as a gully thermokarst formed in the summer of 2003 on the headwaters of the Toolik River near Toolik Lake.  During the summer of 2004 (Fig. 11.12), the gully widened and deepened to a depth of several meters and became 150 m long.

Thermokarst Formation Delivers Major Sediment Impact to Streams

Has the rate of thermokarst formation increased in recent decades as the climate of the Arctic warms?  Thermokarst features are often too small to be seen on satellite images but can be seen on aerial photos.  Bowden et al. (2014) compared 1970 photos from the Toolik area with modern aerial photos and found a significant increase in the number of thermokarst hillslope failures.  Moreover, a 2006 low-level aerial survey (Bowden et al. 2008) showed at least 34 active thermokarst features in a 25 km x 25 km area between Toolik Lake and areas east of Happy Valley to the north.

The amount of soil that is moved when there is a thermokarst event is surprising large.  One measure (Bowden et al. 2014) was of a 100 m long gully several meters deep that suddenly formed in a small stream flowing on the surface of the tundra.  Some 2000 m3 of soil was displaced in 2-3 years or 4000 tons of sediment.  “Over a period of 2-3 years, this single thermokarst feature in a small (0.9 km2) sub-watershed on the Toolik River delivered 18 times more sediment than would normally be delivered by the entire 143 km2 upper Kuparuk River over the same time period”.

Bowden et al. (2014) indicated that thermokarst hillslope failures in the foothills of the Brooks Range substantially alter the loadings of sediments and nutrients into headwater stream ecosystems.  These loadings can persist over many years, and even small thermokarst features can affect long reaches of headwater streams.  Thus, even a low density of thermokarst features might have widespread impacts on arctic headwater stream ecosystems.  As permafrost continues to warm and begins to thaw under the influences of continued warming in the Arctic, thermokarst terrain will likely become more extensive, and hillslope failures in foothills of the Brooks Range will become more numerous.  The expectation is that between now and 2100 a considerable portion of the permafrost in the Arctic will thaw (Schuur et al. 2011) and the area of thermokarst terrain will likely increase substantially.

Permafrost Degradation Changes Surface Hydrology

Within the area with ice-rich permafrost and poor drainage conditions, permafrost degradation will lead to significant ground surface subsidence and ponding (“wet thermokarst”). The ground will become over-saturated, which could cause trees to die (Osterkamp et al. 2000; Jorgenson et al., 2001). Permafrost degradation on well-drained portions of slopes and highlands will proceed in a form of “dry thermokarst”. This process will further improve the drainage conditions and lead to a decrease in the ground water content (Hinzman et al. 2005). Changes in the active layer thickness and permafrost continuity will affect ground water and river runoffs.”

12.  Lake LTER Chapter

Figure - Lake Chapter

Lakes and ponds north of the Brooks Range

These were formed by glaciers that advanced out of the Brooks Range over the foothills and later retreated back to the mountain valleys leaving boulders and glacial till, which is defined as unsorted glacial sediment; aggregations of till alongside or at the ends of glaciers have formed end and lateral moraines.  After the glaciers retreated, large pieces of ice remained behind in the till; lake basins were formed when these pieces melted.  Large lakes also formed behind end moraines that blocked valleys.  Near Toolik Lake (18 m deep), lakes lie on surfaces resulting from glaciations of approximately 12-25 ka (thousands of years), 60-100 ka, and 250-300 ka in age (Luecke et al. 2014).  In the time since the glaciations, the land surfaces have changed and affected the number and size of streams and lakes.  Thus, in the 12-25 ka glaciation surfaces, greater than 3% of surface is covered by lakes and lake-areas are relatively larger.  On the 60-100 ka age surfaces, erosion and solifluction have led to stream channel disappearance, lessened lake depths, and a reduced number of lakes. Less than 0.2 % of the surface of the 250-300 ka surface is covered by lakes and these are relatively smaller than on surfaces formed more recently.  There are, however, well-defined stream channels connecting the lakes (Fig. 12.1).

Toolik Lake contains quite high amounts of dissolved organic matter, so sunlight penetration is hindered.  The euphotic zone, the depth of 1% penetration of light (where light allows phytoplankton net growth), is 6-7 m.  There is 24 hr light several months in summer; there is 24 hr darkness for several months in winter.  Thermal stratification occurs in lakes >5 m soon after ice-out and remains whole summer just like temperate lakes.  Deep waters are 4-5oC and upper waters warm to 14-18oC.

Permafrost effects

Each summer, a layer of unfrozen soil forms above the permafrost; this layer is approximately 40 cm thick but ranges from 28-50 cm (Kling et al. 2014).   Because the permafrost prevents deep drainage, the soils retain the precipitation in the upper layer and are usually moist despite the low rate of precipitation.  When precipitation occurs, the water is not stored but moves relatively rapidly through the catchments in water tracks, streams, and downstream ponds and lakes.  There is, therefore, a relatively rapid turnover of water content in lakes.

A thaw bulb always forms beneath lakes because of the heat movement from lake into the surrounding soil.  If this thaw bulb enlarges enough, then the frozen ground that often makes a dam may thaw and the lake will drain.  There has been a recent drainage of thousands of arctic lakes, especially in regions without permafrost.

Jade Lake is Mostly Dry but Some Summers it Overflows

The whole process of lake formation and disappearance is illustrated by the formation and draining of Jade Lake, a 15 m deep lake in the Toolik Lake watershed.  One of the streams that enters Toolik Lake from the south was blocked by the last glaciation; the resulting end moraine now dams this stream and creates Jade Lake that lies to the southwest of Toolik Lake.  There is, however, a leak in this dam, a small unfrozen tunnel of glacial till or bed of gravel without permafrost at the bottom of the dam, a dam which otherwise is filled with permafrost.  Each summer water flows down the stream and down the thawed soil in the valley.  Some small ponds form in the bottom of the dry lake every summer and drain through the dam in weeks.  The large Jade Lake only appears when there is relatively high rainfall in the late summer (Fig. 12.2).   This lake then drains during the late summer and over the next four months of winter.  This flowing water from Jade Lake stays below ground and enters Toolik Lake at the depth of several meters below the surface.  In 2018 there was 14.8 m of water in the lake on 1 September; the water level recorder in the lake recorded a slow fall in the level and complete drainage by 4 March 2019 (Fig. 12.2).

As noted, this is the only lake in the world where this intermittent occurrence of a lake has been reported.  Here there are 30 years of observations and only three or four times did a good-sized lake appear.  It is certainly true that stream water does drain down through the watershed every summer and there is water movement even when no water appears above-ground in the streambed or on the bottom of the dry lake.  Evidently, within the dam there is enough water movement containing enough heat to keep the leak open for many thousands of years.  Further evidence of great age is the lake sediment on the bottom of the dry lake and the lack of shrubs and woody vegetation on the bottom and sides of the lake basin.  It is not understood just why this happened at only one place.  And what are the rare conditions that have kept the drainage open only in this particular end moraine?

Ice sheet duration

In Toolik Lake, the date of complete ice melt ranges from June 8 to July 1.  Freeze-up of large lakes like Toolik occurs from September 22 to October 10 while smaller lakes freeze 1-2 weeks earlier.  The thickness of the winter ice on Toolik Lake is 1.5-1.8 m; the thickness depends on the insulating snow cover, so more snow cover will limit heat transfer from lake water to the cold winter atmosphere, thereby decreasing ice thickness.

Physical and Chemical Properties

The temperature and circulation of Toolik Lake in summer are very similar to those of temperate lakes (Fig. 12.3).  The upper 4 m continually mixes and the hypolimnion (deeper layers) remain close to 4oC.  Because the algal primary production is low and occurs only in the upper 5 m, the hypolimnion (deeper layers) accumulates only a little organic matter and retains oxygen at close to saturation levels.

In the Toolik region, lake chemistry varies greatly even in lakes quite close to each other (Luecke et al. 2014).  The differences are due to glacial history.  Lakes surrounded completely by the most recently glaciated landscape have relatively high conductivities while lakes found on the oldest surfaces are dilute with the lowest conductivities and lowest major ion concentrations because of the slow long-term weathering of the dominate minerals, limestone and dolomite.  Toolik Lake is influenced by landscapes of mixed age and its chemistry reflects mix of difference age geological surfaces.  In lakes with mixed age surfaces in their watersheds, the pH is around neutrality 6.7-8.1.

The nutrient concentrations in all lakes in this region are very low and are dominated by organic forms.  The dissolved organic carbon (DOC) in most lakes is from 200 to 1000 µM while the dissolved inorganic N (DIN) and P (DIP) concentrations in surface waters are below 0.2 and 0.1 µM, respectively, and frequently are too low to measure.  The organic nutrient forms of DON are 5-20 µM and of DOP is seldom above 0.2 µM; nitrogen release from sediments is very low.  Nitrogen fixation, the conversion of atmospheric nitrogen into a combined form (such as ammonia) through chemical and especially biological processes, is low in Toolik Lake but provides 75% of N input to some other lakes (e.g., Fog2).  Photosynthesis in Toolik Lake is driven mainly by pelagic (open water) recycling of nutrients.  An important role in this pelagic recycling is played by zooplankton.

Toolik and nearby lakes often contain high concentrations of carbon dioxide and methane dissolved in their water column; for this reason, they are a source of these greenhouse gases to the atmosphere (Kling et al. 1991).  There are three sources: First, gases in soil water directly entering the lakes or entering via streams resulting from plant and microbial respiration.  Second, microbial respiration in lake sediments.  Third, the respiration of DOC and particulate organic carbon entering from land.

Lake Food Webs of the Planktonic and Benthic Species

The lakes in the low Arctic have somewhat less predator diversity than is found in temperate lakes but a lot more predator diversity than in lakes in the high Arctic.  In one Greenland lake and a large Canadian lake (Hazen) there is only one fish species, arctic char (Hobbie 1984). The cause of the lack of diversity can be the low amount of productivity in high Arctic lakes.

Phytoplankton species diversity ln Toolik and nearby medium and large-sized lakes is high with over 140 taxa identified from Toolik Lake (O’Brien et al. 1997).  The most abundant are the very small blue-green algae but most of the biomass is in flagellates in the divisions Cryptophyta, Chlorophyta, and Chrysophyta.  Larger but rarer are large-celled diatoms (Bacillariophyta) and large dinoflagellates (Pyrrophyta).

The overall structure of the food web (Fig. 12.4), modified from O’Brien et al. 1997 with permission?) in these lakes is similar to those of temperate lakes, except that the number of fish species is greatly reduced in the low Arctic (Hershey et al. 1999). In some small and shallow lakes that completely freeze there are no fish; when this happens, the highest trophic levels can be occupied by invertebrate predators.  Several other key aspects of the food webs of lakes vary with lake size (O’Brien et al. 1997).  Chlorophyll concentration in surface waters is greater in the smaller lakes, as is the biomass of zooplankton. The abundance of crustacean zooplankton is similar among different size lakes, but that is because these small, fishless lakes are frequently dominated by large-bodied Daphnia middendorffiana 3 to 5 mm in length (Fig. 12.5).

Algal and Bacterial Production

The planktonic bacteria of Toolik Lake reveal interesting seasonal patterns tied to inputs from the land plants (Leucke et al. 2014, Crump et al. 2003).   There is little change in the species of bacteria and their low productivity during the long period during the fall and winter months beneath the ice.  As soon as the inlet streams began to swell with the snow meltwater, the bacteria production in the lake reached its annual peak of production.   This suggests a rapid growth of bacteria adapted for growth on labile organic material extracted from the plant litter by water from the melting snow and flushed into the lake.  This peak activity occurred beneath the ice and in water close to the freezing point.  When the spring runoff from land slowed and the ice finally left the lake, the bacterioplankton community shifted again to the summer community with input from lake primary producers.  In late summer, bacterial productivity rates fell, and the winter bacterial species and low productivity rates took over.  We have also noted that during storm events later in the summer the DOC in the lake also increased but at this time of year there was no corresponding increase in bacterial activity.  These changes in bacterial species and their productivity over the entire year was described for the first time in this arctic system but certainly happen in all lakes with an ice cover.

Algal primary production (PP) in arctic lakes, and in Toolik and surrounding lakes, is very low because of there is only a short open water season and only low rates of nutrient supply.  As noted earlier, 50% of the annual PP in Lake Schrader, a deep lake in the Brooks Range, usually occurred beneath the ice cover (Hobbie 1964).  In one exceptional year, the ice cover lasted until 26 July and 83% of the PP occurred beneath the ice cover.  In Toolik Lake, PP rates are highest immediately after ice-out and then become lower due to nutrient limitation during the summer (Fig. 12.3).  Stream inputs of nutrients due to summer storms do provide more nutrients but these are also exported by streamflow to other lakes.  Another source of nutrients is by upward mixing of nutrients from deeper waters (MacIntyre et al. 2006).  Tests of PP with added nutrients show that both N and P are necessary.  In shallow lakes, those less than 8 m deep, most of the primary production does occur at the surface of the benthic sediments.


Nanoflagellates, ciliated protozoans, rotifers, and copepod nauplii make up most of the zooplankton community in the lakes near Toolik.  Heterotrophic nanoflagellates can consume a substantial portion of bacterial productivity (Hobbie and Laybourn-Parry 2008).

Compared with temperate lakes, there are relatively few species of crustacean zooplankton existing in this region.  Only seven common species are present in over 100 lakes that have been sampled; abundance and distribution is affected by lake size, depth, and the presence of fish. Two large bodied zooplankters, Daphnia middendorffianna and Heterocope septentrionalis, are more abundant in small lakes than in medium and large ones (Fig. 12.5) and appear to be eliminated by fish predation in the medium and large lakes.  O’Brien et al. (2004) reported that abundance of D. middendorffiana was twice as high in fish-less lakes than in lakes with fish.

It is obvious that fish predation controls the abundance of zooplankton in arctic lakes and that predation is much reduced when zooplankton are nearly transparent.  Yet zooplankton are sometimes colored with a wide variety of pigmentation. For example, several copepod species range from bright red to blue to relatively clear (Fig. 12.5).  There are two factors at work here.  One is the necessity for photo-protection against sunlight, especially around the summer solstice.  The second is fish predation.   Luecke and O’Brien (1983) found that highly pigmented, large-bodied zooplankton dominate fishless ponds whereas lakes with fish are occupied by relatively transparent or small-bodied zooplankton that avoid the top few meters of surface water.  For example, crustacean zooplankton biomass was five-fold higher in shallow lakes without fish than in deeper lakes with arctic char, arctic grayling, lake trout, or sculpin.


Six species of fish are found in the lakes and streams near Toolik, and these species are all native, a rare occurrence in North America where introduced fish are everywhere.  Lake trout (Salvelinus namaycush), burbot (Lota lota), and arctic char (Salvelinus arcticus) occupy the highest trophic levels and feed extensively on benthic invertebrates; some individuals also may become piscivorous. Arctic grayling (Thymallus arcticus) and round whitefish (Prosopium cylindraceum) feed on benthic invertebrates and occasionally zooplankton, and slimy sculpin (Cottus cognatus) is a bottom-dweller who also feeds on benthic invertebrates.  Lake trout and arctic char are found only in deep lakes that are part of well-established drainage systems (Hershey et al. 2006) and earlier mention in section on Lake Peters.  Lake trout function as a top predator in these lakes, feeding on a mix of invertebrate and vertebrate prey.  When lake trout are present, they not only have large impacts on the abundance and distribution of their prey but also have significant effects on lower trophic level organisms.  For example, lake trout reduced the numbers of slimy sculpin and restricted remaining sculpin to near-shore habitats.  As a result, benthic invertebrates preyed on by sculpin increased their number (Hanson et al. 1992).

Limnocorral Experiment

In 1983 to 1985 a limnocorral experiment was established in one of the deep bays of Toolik Lake (O’Brien et al. 1992) (Fig. 12.6).  Each 62 m3 corral was made from a plastic tube 5 m in diameter and 5-6 m in depth attached to a heavy wooden floatation collar and open to the sediments.  Four corrals were held together in a large square and anchored in the center of the bay (Fig. 12.7).  This experiment, and many that followed, looked at ecological effects of increased quantity of nutrients on rates of primary production and reproduction, survival, and growth of biota, from bacteria to fish.  Certainly, climate change or human introductions will bring loss or addition of species.  One result of fertilization of N plus P was the expected large increase in the phytoplankton biomass and PP but the Chrysophyte’s and Chlorophyte’s biomass increased far more than other types of algae.  Bacteria too increased followed quickly by their predators the heterotrophic nanoflagellates.   However, the treatment of adding fish did not work out well because 62 m3 was too small a quantity of water to provide enough food for even a single fish.  An ingenious solution was to keep a fish in a wire mesh basket and put the basket inside the corral for only a few hours a day.  In this way, the fish predation was greatly reduced while the fish in its basket survived in the waters of the lake.

Steel Pier Removal

In 1975, the Toolik scientists decided that one of these tremendously heavy and immovable steel I-Beams of the camp pier (Fig. 12.6) would be an ideal place to keep track of the water level in Toolik Lake every week.  Bad idea.  In one of the following years there was a flood of stream runoff in the spring that raised the water level while the steel frame was still frozen into the ice, hence lifting the steel frame.  When the frame settled back down into the bottom muds after the ice-melt, it was at a slightly different elevation and no good for the long-term record of the lake water level.  Another reason it was a “bad idea” was that the steel frames were removed when the construction camp was demolished in the late 1970’s.

Whole Lake Experiments

The experiment in Lake N2 some 500 m NW of Toolik Lake, compared processes for 12 summers in the control and fertilized halves of an 8 m deep lake.  The lake was divided in half with a polyethylene curtain extending to the bottom; this large curtain was difficult to install and remove after so many years (Fig. 12.8).  Primary production in the fertilized half-lake quickly increased to 3-5 times the untreated half (Fig. 12.9).  This high PP dropped dramatically when fertilization stopped after 1990 and the reduced rate continued for the next 6 years.  The measurements of the fluxes of nutrient leaving the sediment were much more interesting in that DIN began to flux out after 2 years of fertilization while DIP did not begin to flux out until after 4 years of fertilization.  This delayed flux of DIP was likely due to the low oxygen concentration (fell below 1 mg L-1) in the deep waters, which began to release DIP in the 5th year of fertilization as iron minerals were reduced (Fig. 12.10).

A second whole-lake fertilization experiment was conducted on Lake N1, that lies close to Toolik Lake, from 1990 to 1994.  There was no curtain and comparisons of rates and organisms were made before, during, and after fertilization.  Nitrogen and phosphorus were added to this lake during summer months at a rate of approximately four times natural loading (Lienesch et al. 2005).    Both PP rates and chlorophyll a concentration increased six-fold.  Another rapid change was of the density of snails that increased from less than 1 to more than 3 m.2 in the years of fertilization.  The growth rate of lake trout responded positively to this increase in snail abundance (Fig. 12.11).  An important exception to the rapid recovery back to pre-fertilization conditions was that deep-water oxygen concentration remained quite low through the summer of 1998 and had not completely recovered by 2010 (Lienesch et al. 2005).  It is likely that the sedimented phytoplankton that accumulated during the years of fertilization continued to provide a labile substrate for bacterial respiration long after the fertilization was ended.  The results of this experiment show that it is important to continue measurements for extra years or decades in order to understand a variety of processes that may operate on different time scales.

Nearby lakes with similar food webs have allowed experiments where lake trout density was changed (Merrick et al. 1992).  When adult lake trout were completely removed there was a rapid recruitment of both juvenile lake trout and arctic grayling.  These relatively abundant young fish provided food for burbot, a large fish formerly present but quite rare, whose population then increased.  Another experimental result of lake fertilization depended upon whether large fish were present.  When large fish were present, large-bodied zooplankton such as Daphnia were consumed and not able to respond to the increased phytoplankton.  Without large-bodied zooplankton, microzooplankton increased greatly in abundance.  These compensatory changes demonstrate that these arctic food webs are complex and usually quite stable.  These results in the Arctic are similar to those from experiments in temperate lakes (e.g., experiments by Carpenter et al. 1996 and Pace et al. 1998).

Response to Climate Change.

In Toolik Lake, with data beginning in 1975, the average mid-summer temperature has increased but the increase is not statistically significant; mean annual air temperatures are similar and also show a non-significant increase.  The results are not unexpected given that most warming in the Arctic has been in the winter (ACIA 2004).  Most of the other physical, chemical, and biological measures made in Toolik Lake have also shown no obvious changes in this time-period.  For example, nutrient and chlorophyll concentrations show no statistically significant change during this period.  There were, however, large year-to-year differences as seen in the 25-year record for July in the concentration of chlorophyll a (Fig. 12.13).

There has been, however, a significant and long-term trend of increase in alkalinity in Toolik and other lakes.  Alkalinity is the chemical capacity of the water to neutralize acid.  It is also called a buffering capacity.  Therefore, something is changing the chemistry of the incoming water (Fig. Lake 12).  Through study of isotopes of strontium isotope in the inlet stream to Toolik Lake, Keller et al. (2007) deduced that the most likely source of the alkalinity is weathering of previously frozen glacial till.  Slow warming would thaw till that had been frozen for thousands of years and over a series of summers this layer would become wet for longer and longer periods.  When this happens, the mineral apatite (calcium phosphate) will dissolve to some extent and deliver alkaline chemicals plus phosphate to streams.  In fact, the only stream with high phosphate concentrations drains a small area of tundra where several meters of gravel have been mined for road construction in the mid-1970’s.  It is very likely that the removal of the gravel led to thawing of the underlying glacial till and a dramatic increase in alkalinity and phosphate in the stream.  This process is likely happening in tundra streams in many places at a very low rate caused by a very slow thawing of the active layer at the top of the permafrost; the only stream where it is at a high rate is where gravel was mined and underlying glacial till abruptly thawed.  It is also likely that in other streams terrestrial and aquatic plants remove all of the phosphate, so it never builds up in the streams or lakes.   We conclude that the buildup of alkalinity in the lake waters is not a problem but that it is a signal that a slow process is occurring that could well increase phosphate release to lakes as the permafrost thaws.

Predictions of Future Ecosystem Processes in Arctic Alaskan Lakes

Climate models predict an arctic warming of 4oC to —6oC over the next century; most of the change will be during the winter (Cherry et al. 2014) and will be coupled with a 10% increase in precipitation.  Predictions for northern Alaska, however, are for 1.5 to 3-fold increases in precipitation.  The future Toolik region will be warmer and wetter.   But at Toolik there have been no real changes in the summer lake temperatures and lake productivity since the 1970’s, although in nearby regions Hinzman et al. (2005) have noted increases in air and soil temperatures.

The increase in lake summer temperatures is likely to cause changes in dominate plankton species.  Yurista (1999) found that present-day Daphnia middendorffiana have high food ingestion rates at cold temperatures and low assimilation rates at warmer temperatures.  They will not survive in the warmer lakes of the future and would likely be replaced by temperate zone Daphnia species.  A similar finding came from a bioenergetics study of the effects of climate on fish by McDonald et al. (1996) who concluded that increased lake temperatures would greatly reduce lake trout success in low-Arctic lakes.  They prefer water of 10 °C with oxygen concentrations above 6 mg L-1 and are stressed at temperatures above 15°C.  If surface water temperatures rose by 2oC, the suitable summer habit would decrease by 30 % (Hobbie et al. 1999).  Increased nutrient loading and decreased oxygen in the deep water would also reduce lake trout habitat.  The detailed data on fish populations near Toolik Lake reveal that the fitness of arctic char, arctic grayling, and lake trout, defined as the length-weight relationship, declined in summers when surface water temperatures exceeded 15oC for extended periods (Leucke et al. 2014).

As a part of future climate change, it is likely that precipitation patterns and amounts will change.  These are difficult to predict but certainly more precipitation will fall as rain rather than snow.  More incoming stream water containing increased solutes and along with warmer temperatures will result in an increase in algal production.  This production increase will occur even when there are only small increases of nitrogen and phosphorus.  The warmer temperatures will likely allow zooplankton to respond to the increase in algal production and become more abundant but only when the upper levels of lakes become warmer than 15oC (C. Luecke, unpublished data).

It is also true that lake organisms that thrive in these low Arctic ecosystems with low productivity and low water temperatures may not survive well when algal production and water temperature increase (ACIA 2004).  Certainly, a rapid increase in air and water temperatures, conditions that are very likely over the next 20 years, will make it difficult for any adaptations to occur by organisms now present; this may allow subarctic organisms to invade (Hellmann et al. 2008).

13.  Arctic Springs: A Rare Ecosystem

Frigures – Arctic Springs


Spring-fed streams with perennial flow and relatively constant water temperatures of 3-7oC or more are widespread on the eastern North Slope of Alaska (Fig. 13-1, Kane et al. 2013), where most headwater streams freeze completely during winter.  There are actually two springs shown in the figure that are true hot springs, Red Hill (33oC) and Okpilak (49oC).  The rest of the North Slope springs are either warm or cold. Warm springs (named mountain springs, hereafter), such as Ivishak Spring at its source in Fig. 13-2, have winter water temperatures ranging from ~4o to 13oC—remember that air temperatures range below -30oC during winter which makes water temperatures of 10oC or even 4oC seem warm by comparison (a winter view of Ivishak Spring is shown in Fig. 13-3).  Mountain springs are found where the Lisburne Limestone contacts layers of sandstone along the lower slopes of the Brooks Range.  The groundwaters discharged by these springs flow from aquifers beneath the permafrost layer that are subject to significant geothermal warming.  In contrast with the warmer mountain springs, cool springs (tundra springs hereafter) have winter water temperatures of 1oC or less and are in the foothills.  The sources of groundwaters that feed tundra springs are upstream lakes and aquifers within the deep gravel beds of large rivers.  Although many tundra springs flow year-round, some will freeze when their groundwater sources become depleted during winter.  Overall, spring streams contribute only ~1% to the total headwater stream length on Alaska’s North Slope (Craig 1989), but they also provide 100% of flowing stream habitat during winter.

Biodiversity and Productivity Hot Spots; Fish to Trees

The year-round flowing water provides unique refuges for some few aquatic animals. Figure 13-4 shows several examples, including insects such as stoneflies and caddisflies (adult and an aggregation of pupal cases of caddisfly Ecclisomyia conspersa), the Dolly Varden char (Salvelinus malma), a semi-aquatic bird (dipper, Cinclus americanus), and the river otter (Lontra canadensis).  The shorelines of spring streams also may provide unique habitats for plants (Fig. 13-5), such as bladder ferns (Cystopteris sp.), balsam poplar (Populus balsamifera, Breen 2014), common mountain juniper (Juniperus communis), and sparrow’s egg orchid (Cypripedium passerinum).  Some of these over-wintering animals spread out across the whole region during the summer and enhance the biodiversity of the entire region.

The appearance of the upper reaches of a typical mountain spring stream is a remarkable contrast to tundra because of the green tree growth (Fig. 13-6).  Willow growth is luxuriant near some springs as are stands of hundreds of balsam popular trees, some up to 12 m high (Childers et al. 1977).  This close association of the balsam poplar stands with spring streams is likely due to deep, relatively warm, perennially thawed zones of the riparian soils which facilitates the development of root systems capable of supporting trees (Bockheim et al. 2003).   Radiocarbon dating of a wood fragment sampled from the soils beneath one poplar stand indicated that it originated from a tree that died 670 years ago, providing evidence that some stands have persisted for centuries.

Arctic spring-streams are also hot spots of freshwater productivity. Daily levels of primary production measured during summer for a spring stream on the North Slope of Alaska, for example, were comparable with some of the most productive stream ecosystems known, although annual levels were more modest due to light limitation for much of the year. This high primary production supports invertebrate biomass and productivity similar to stream ecosystems at much lower latitudes.

The Spring Stream-Aufeis Complex

In winter, water flowing from a spring cools and eventually freezes; it may then build up ice on top of already existing river ice or at a narrow place in its channel where ice increases until the channel is blocked.  The combination of thickening surface ice and permafrost below restrict stream discharge which causes overflow.  This overflow ice is called aufeis (from the German “on ice”) and builds on top of stream channels, ice-covered rivers, or may even extend previously off-stream tundra (Fig. 13-7, Fig. 13-8, Fig. 13-9).  Aufeis on tundra may last for most of the summer; this can cause near-absence of vascular plants.  By late winter, aufeis may be a massive 3-7 m thick and cover areas up to 20 km2 (Alaska) or 80 km2 (Siberia).  In some places, the bottom surface of the aufeis is always wet due to the thick insulating layer of ice.

During the summer, the aufeis may provide meltwater flow to downstream habitats that otherwise would dry up.  This subsidy to summer flow will also keep water temperatures cool and may allow movements of fish (Sandstrom et al. 2009) along stream corridors, affecting ecosystem processes.  This role of aufeis in maintaining flows during summer may be especially significant to Dolly Varden char, which on the North Slope are uniquely associated with both spring streams and aufeis.  Migrating Dolly Varden rely on late-summer meltwater from aufeis to gain access to upstream habitats for overwintering.   Some female Dolly Varden even overwinter in channels beneath aufeis, rather than in warmer upstream spring streams, to maintain low metabolic rates and thus conserve energy supply.

During winter, the wet bases of aufeis allow adjacent groundwater to remain unfrozen. This affects biodiversity, ecosystem productivity, and nutrient cycling.  For example, that the biodiversity of stoneflies (Plecoptera) increases near perennial springs and aufeis.

Finally, after summer thawing, aufeis leaves areas in tundra landscapes that are called aufeis barrens (Fig. 13-9), because of the near absence of vascular vegetation due to ice cover during much of the growing season.  Aufeis barrens are distinctive features that provide reliable indicators of aufeis locations during winter

What is the Source of Mountain Spring Water of the North Slope?

Hydrological modeling and water chemistry such as solute concentrations and isotopes of hydrogen and oxygen indicate that the water for many North Slope mountain springs originates at high elevations on the south slope of the eastern Brooks Range (Fig. 13-8).  Here the permafrost layer is discontinuous, and the abundant limestone and dolomite bedrock provides networks of cracks, fissures and faults allowing the downward penetration of precipitation to groundwater reservoirs. This groundwater then flows to the north at 30-85 m/year beneath the ~250 m thick permafrost layer of the Brooks Range and eventually passes up through the surrounding permafrost through areas of unfrozen ground called taliks, to form springs along the bases of mountain and hillslopes of the North Slope. The complete journey may take as long as 1000 – 1500 years (Kane et al. 2013).  Deep networks of faults in the Lisburne Limestone formation of the Brooks Range appear essential for maintaining the groundwater-fed systems of the eastern North Slope, many of which are strongly associated with such bedrock features.  Because the groundwater reservoir is contained within networks of faults that extend deep into the mountains, it is warmed by low-level geothermal heat and is also maintained at relatively constant temperatures year-round.  Given the variety of histories of the water, it is not surprising that the average annual temperatures for the mountain springs range from 0.5o to 33oC but that each spring has nearly a constant temperature over the entire year.

History of Arctic Spring-Stream Research 1907 – 1990

As discussed in Chapter 2, Ernest de K. Leffingwell pioneered research on permafrost in northern Alaska in the early 1900s.  He visited Shublik Spring, which flows into the Canning River, and noted that the water temperature was 10oC in June. This temperature, about 8°C above similar streams for that time of year, was an early clue to the geothermal origin of the spring’s water.  At the same time, the Canadian Arctic Expedition’s Frits Johansen visited Sadlerochit Spring and collected snails, fingernail clams, mayflies, stoneflies, caddisflies, and amphipods (Johansen 1919, 1921).  Present-day flow rates are 680 L/s for Shublik Spring and ~1000 L/s for Sadlerochit Spring.  Both are relatively close to the Beaufort Sea coast (~32-37 km inland) and were well known to the Iñupiat at the time of first scientific description (Leffingwell 1919).

Exploration was renewed in earnest in the 1970s and 1980s, driven primarily by the developing oil resources in the Prudhoe Bay region. One proposal in 1972 was to develop a gas pipeline from Prudhoe Bay to the Mackenzie River Delta.  These developments stimulated surveys of available water resources and studies of potential environmental consequences to regional fisheries resources of the planned transportation infrastructure.  As a consequence, reports were published during the 1970s and 1980s by the United States Geological Survey (USGS), United States Office of Naval Research (Kalff and Hobbie (1973) on Shublik Spring), and the Canadian Arctic Gas Study (Toronto) that provided detailed descriptions of the physical hydrology and animal communities of numerous spring-stream and aufeis ecosystems.  For example, Childers et al. (1973, 1977) conducted the first comprehensive survey of the physical, chemical, and hydrological characteristics of spring-stream habitats of the North Slope and other expeditions located 18 spring-stream ecosystems.  Hall & Roswell (1981) provided the first quantitative assessment and south slope locations of the potential sources of recharge to the North Slope springs.  In addition to these studies, Craig & McCart (1975) collected extensive physical, chemical hydrological and biological data from 55 streams from Prudhoe Bay to the Mackenzie River Delta.  The 55 streams they studied were separated into three categories: mountain streams, tundra streams, and spring streams (mountain springs).   Key ecological attributes differed across these categories. For example, the density of macroinvertebrates within spring streams (~1000-100,000 individuals/m2) was greater than densities in tundra streams (~100-3000 individuals/m2), which in turn exceeded those shown for mountain streams (~30-100 individuals/m2).

Spring-Stream Ecosystem Field Work: 1990 to 2004

The Arctic LTER Program used the Craig and McCart (1975) classification of arctic streams in a comparative ecosystem study of headwater streams, particularly spring-streams. Four mountain springs (i.e., springs with discharge originating from deep groundwater reservoirs associated with the Lisburne Limestone formation of the Brooks Range) and examples of other stream types (i.e., three glacier streams, four mountain streams, and four tundra streams) were selected for study.  Mountain spring-streams had significantly higher stream bed stability (mean total bed particle movement ranged from 0-4% over the summer), compared with tundra streams (4-49%), glacier streams (23-52%), and mountain streams (66.0 – 97%).  The high bed stability for mountain spring-streams is attributed to their relatively constant rates of discharge.

Mountain spring-streams also did not freeze during winter, whereas mountain, glacier and tundra streams froze completely, with the exception of a single mountain stream (Ivishak mountain stream) that was closely associated with a mountain spring (Ivishak Hillslope mountain spring). The mean daily January temperatures of the four mountain springs studied, in fact, ranged from 0.6 to 5.5oC and mean monthly temperatures generally fluctuated by only ~3oC.  These unique physical characteristics (i.e., stream bed stability, relatively constant temperature and flow, no freezing) set the spring streams apart from other stream types.  The biology among streams also differed dramatically, as bryophyte biomass, algal biomass, and macroinvertebrate abundance and biomass were significantly higher in mountain spring-streams than other types of streams (glacier, mountain, and tundra streams).  In fact, mean bryophyte biomass (48.5 g m-2) and mean macroinvertebrate abundance (67,781 individuals m-2) and biomass (4,837 mg dry mass m-2) exceeded those of non-spring ecosystems by one to three orders of magnitude (Huryn et al. 2005, Parker & Huryn 2011).

In addition to biomass and abundance differences, spring streams also had larger and more complex food webs than other stream types, averaging ~50 trophically interconnected taxa while other stream types contained ~32 trophically interconnected taxa. They also had higher levels of connectance and linkage density and longer mean food-chain lengths (i.e., 2.4 steps vs. 1.5 for glacier streams and 1.8 for mountain and tundra streams) that were positively related to indicators of ecosystem productivity (consumer biomass). In fact, the Ivishak Hillslope mountain spring had a food-chain length of five steps from primary producer (diatoms) to the top predators of Dolly Varden, American dipper, and river otter (Parker & Huryn 2013).

These early studies documented that mountain spring-stream ecosystems are unique habitats of the North Slope and are characterized by unusually consistent and stable habitats with warm water and year-round flow. These biotic responses, however, were not necessarily relevant to the major winter period with no sunlight and air temperatures continually below 0oC.

Spring-Stream Ecosystems: 2004-2010

To understand the true ecological complexity of the mountain spring-streams, it was crucial to have ecological data from the winter.  While the water temperature does not change, the major difference is the light availability and the changes that will occur in energetic relationships between producers and consumers.  The major question was how scientists could access springs at remote locations on the North Slope.  In the summer, helicopter transport was available at Toolik Field Station where for a decade the summer research had included helicopter support to sample remote sites such as at the large Anaktuvuk Fire Scar and rivers and lakes away from the Dalton Highway.  There had been no winter helicopter travel.  Luckily, two developments made it possible.  First, an experienced helicopter pilot working out of the Toolik Field Station, Edward S. Serrano (formerly of North Pole, Alaska, Fig. 13-10), in the early 2000s assured us that year-round helicopter travel to remote spring stream locations in the Arctic National Wildlife Refuge (ANWR) would be possible, regardless of winter temperatures and snowpack. Second, the NSF Office of Polar Programs became interested in the potential for winter field research by the ARC-LTER, which previously had been focused on the summer season, and would provide support for year-round logistics.  We secured funding for a three-year study of the effects of the annual polar light-regime on the bioenergetics of a single mountain spring-stream ecosystem, Ivishak Hillslope Spring (Ivishak Spring, hereafter (Figs. 13-1 & 13-3), in ANWR (69.024˚, -147.721˚), about 88 km ENE of the field station.

The first requirement was year-round support at Toolik Field Station, usually closed during the winter. This was resolved by modifying the cooperative agreement between NSF and the Toolik Field Station, and the station became active year-round during 2006-2008. The second requirement was winter transport by helicopter. This was provided by a helicopter that flew from Fairbanks to the Toolik Field Station for our 3–4-day monthly trip to Ivishak Spring from September through May, months when regular helicopter support was not available at the field station. The third requirement was winter shelter at the field site.

This shelter was provided in the form of an apple hut, formally known as the Igloo Satellite Cabin (Icewell One, Tasmania, Australia).  This is a dome-shaped, insulated, fiberglass cabin with an inside diameter of ~3 m and an internal peak height of ~ 2 m (Fig. 13-11). They are widely used as emergency shelters in Antarctica and are bright red.  Some scientists at the Toolik Field Station referred to the unit we used as the tomato rather than an apple. Once assembled, an apple hut can be transported by slinging it below a helicopter, which is how our unit was transported from the Toolik Field Station to Ivishak Spring, and then returned after its initial deployment in 2006.  Our unit was equipped with two sleeping platforms, a folding table, and storage space.  Heat was provided by a small wood-burning stove that was also used to heat water for meals.  We used compressed-sawdust logs as fuel. Due to ANWR permit restrictions, the apple hut was not allowed at the field site from June through August due to the potential that its presence would interfere with the wilderness values expected by potential visitors raftering on the Ivishak River, a National Wild and Scenic River. Consequently, our apple hut was transported by helicopter from the Toolik Field Station to Ivishak Spring each September and removed from the field site in May (Fig. 13-11).  During the summer, we were transported to the spring by helicopter and camped in tents.

Year-Round Field Studies at Ivishak Spring: 2006-2008

The Dolly Varden char in the North Slope springs has populations of non-migratory dwarf fish in Galbraith Spring (near Galbraith Lake), Shublik Spring, and Sadlerochit Spring.  However, the population in Ivishak Spring is composed primarily of juvenile fish that will eventually migrate to the coastal Beaufort Sea where they will become full-sized adults (~ 70 cm in length).  These Ivishak Spring Dolly Varden have a mean body length of 9.2 cm (based on 1,454, individuals sampled) with a range of 5.5 to 19.0 cm.  Most individuals are < 15 cm, however.   A few so-called sneaker males, however, do become sexually mature at relatively small sizes (e.g., 15.0-19.0 cm) and will leave the spring only during attempts to clandestinely fertilize the eggs of spawning sea-run adults that establish redds (i.e., nests) in the main river channel nearby.  In our study of Ivishak Spring, we recorded the length and weight of all the Dolly Varden.

For 30 months, we measured daily O2 cycles, nutrient uptake, algae and bryophyte abundance and composition, invertebrate abundance, Dolly Varden abundance and biomass, air and water temperatures, water input and chemistry, and light levels.  The results of our year-round study (Fig. 13-12) showed that annual patterns of ecosystem primary production (algae and bryophytes in this case) did indeed fluctuate dramatically due to the seasonal cycle of light, but were also extraordinarily high during summer, given the arctic context. We also found that the stable, relatively warm water temperatures during winter limited ecosystem respiration.  That is, the greatly reduced primary production in winter did not provide enough organic carbon to support the metabolism of all the microbes, plants, and animals (Huryn et al. 2014, Huryn & Benstead 2019).

Further detailed analyses showed that the lowest rates of algal, bryophyte, and animal production occurred at lowest light levels rather than at lowest temperatures, supporting the hypothesis of organic carbon limitation rather than a physiological response to temperature per se (Huryn & Benstead 2019, Fig. 13-12).  This winter-warm ecosystem essentially ran out of steam during winter due to light limitation of photosynthesis! This contrasts with most other ecosystems, where seasonal cycles of organic carbon production and demand are coupled (i.e., lower primary production and organic carbon demand in winter, higher primary production and organic carbon demand in summer).  In essence, we demonstrated two important characteristics of arctic spring streams. Firstly, Ivishak Spring is undoubtedly a hotspot of regional productivity; secondly, the uncoupled light and temperature regime of Ivishak Spring drove a unique annual pattern of energetics for this ecosystem.  The organisms are essentially forced to fast during mid- to late-winter.

Data from Ivishak Spring: A Hotspot of Productivity but Winter Survival Test

Peak rates of daily primary production measured at Ivishak Spring (> 4.0 g carbon m-2 d-1) compare favorably with the highest rates reported for relatively undisturbed, open-canopy headwater streams at lower latitudes (~3.2 to 7.4 g carbon m-2 d-1; Huryn et al. 2014). Similarly, annual production by invertebrate primary consumers (i.e., invertebrates that are not predators, 10.1–17.4 g dry-mass m-2 yr-1) is surprisingly high given the location of Ivishak Spring above the Arctic Circle (Huryn & Benstead 2019). These levels are higher than the median estimate reported worldwide in a recent meta-analysis (Patrick et al. 2019), despite annual mean water temperatures ranging from only 4.2˚C to 7.6˚C. The annual production of Dolly Varden in Ivishak Spring is also quite high at ~100–118 kg wet mass ha-1 yr-1 (Fig. 13-13), within the range of highly productive trout streams (~100–300 kg wet mass ha-1 yr-1; Waters 1988).  Although Craig & McCart (1975) pointed out the importance of arctic spring-stream ecosystems as winter refuges, we conclusively demonstrated the ecosystem properties that result in their anomalously high productivity.

Despite the high annual productivity, the winter conditions drastically test survival.  The evidence for this bioenergetic cost (Huryn and Bensted 2019) is as follows: 1) consumer growth rates fell during winter due to lack of food while temperatures did not change, 2) primary production, ecosystem respiration, and daily growth rates of consumers happened at lowest light levels while temperatures did not change, 3) during winter, the Dolly Varden had minimal consumption of prey and the invertebrates had minimal consumption of primary producers, 4) during winter, the Dolly Varden had loss of mass due to forced fasting, and 5) supply vs. demand budgets indicated there was not enough winter prey to maintain a Dolly Varden’s condition.

How Arctic Spring Ecosystems Contribute to Understanding Climate Change

The unusual combination of extreme seasonal fluctuations in light, and relatively constant, moderate temperatures raises questions about whether insights gained from studying Arctic spring-stream ecosystems can be generalized to other ecosystem types.  Certainly, these arctic springs are driven by a mixture of drivers, for example, the different ways of the coupling of light and temperature, that cannot be altered experimentally at large spatial scales.  Comparative analyses among spring-stream ecosystems with variable thermal regimes may also shed light on likely responses of ecosystem organic-carbon dynamics to climate change, especially in the Arctic where temperatures are rising disproportionately due to polar amplification of greenhouse warming (Hinzman et al. 2005, Chapin et al. 2006a, 2006b, Martin et al. 2009).  Northern Alaska has warmed several degrees in the past four decades, resulting in altered river flow regimes (Peterson et al. 2002, O’Neil et al. 2016) and increases in discharge variability (ACIA 2005).  Although the availability of flowing streams during the arctic winter could conceivably expand due to climate warming, it is also likely that the extent of flowing stream habitat during summer will decrease due to summer drought. Under scenarios that include warming and increased summer drying (ACIA 2005; Chapin et al. 2006a, 2006b), multiple emerging roles for year-round flowing spring streams can be envisioned, including their potential as sources of colonizers in the event year-round streams become more widespread due to winter warming (Huryn et al. 2005), or as summer refuges in the event of widespread summer drying.  Finally, predicting climate-driven changes to freshwater ecosystems in the context of the new Arctic is an emerging area for research, yet there are difficulties in assessing such changes without appropriate benchmarks.  Because of the slow passage of the groundwater under the Brooks Range (up to 1000-1500 years), we suggest that arctic springs may provide a stable long-term context that can be used to assess changes in other ecosystems more directly influenced by climate change.  In summary, the uncoupling of light and temperature cycles in arctic spring-stream ecosystems makes them compelling model systems for general research on primary exogenous drivers of ecosystem dynamics and for studying climate change in the Arctic.

Exploring Spring Streams, Aufeis, and Ecosystems: 2016-2018

During summer, 2001, adult stoneflies were collected from a spring stream – aufeis complex on the Ribdon River (this river comes in from the northeast and joins the Sagavanirktok River along the road from Toolik to the coast).   These stoneflies were Paraperla frontalis, a species that specializes in deep groundwater habitats that exchange water with larger, braided river channels; additional populations of this species and other groundwater stonefly species were collected from aufeis fields on the eastern North Slope (Kendrick & Huryn 2014).  Their presence was a surprise because it was believed that they could not live on the North Slope because of the continuous permafrost.  The researchers therefore predicted that aufeis must provide insulation allowing their underlying spring-fed aquifers to remain unfrozen.  This insulation creates a year-round oasis for numerous invertebrates living in the groundwater.

The next research took place at an aufeis that exists year-round on the Kuparuk River and is even visible from space (this aufeis is the white dot that lies inside the blue star in Fig. 13-1) (King et al. 2020, Terry et al. 2020).  The area and volume of this aufeis is greatest during late winter (i.e., April) when it may cover 8+ km2 and reach thicknesses up to ~7 m (Yoshikawa et al. 2007, Terry et al. 2020).  By September, following the summer thaw, only residual ice is present, but the volume depends on summer weather and the amount of ice accumulated the previous winter.  Like other large aufeis aggregations on the North Slope, the Kuparuk aufeis is formed from the discharge of a discrete spring. The aquifer feeding this tundra spring (winter temperature < 1 °C) is probably recharged from a below-ground reach of the Kuparuk River upstream of the aufeis field (King et al. 2020). The intra-permafrost reservoir for the spring is likely a buried paleochannel (e.g., Poole et al. 2002) that intersects with the floodplain surface to provide the spring’s source. This paleochannel is presumably a remnant of a drainage system associated with a Pleistocene glacier that terminated upstream of the present-day aufeis field (Hamilton 1978, Yoshikawa et al. 2007).

To meet the first goal of the study, to assess the hydrophysical conditions beneath the aufeis during late winter, we used both ground-penetrating radar (GPR) and surface nuclear magnetic resonance (NMR) to quantify groundwater resources beneath the aufeis during maximum ice sheet development in April (Terry et al. 2020) (Fig. 14). During field work in April 2017, an ice layer up to 6 m thick (i.e., the aufeis sheet) overlying 3 to 5 meters of frozen sediments (primarily cobbles) was detected.  But, most important, a large region of unfrozen, water-saturated sediments below the frozen surface layers was also detected. In the southern area of the aufeis (again, in the vicinity of a large tundra spring) these features extended ≥ 20 m beneath the sediment surface to form a ~13-m thick layer of unfrozen, saturated sediments, indicating that a perennially unfrozen ground-water habitat did indeed occur beneath much of the aufeis field (Terry et al. 2020). Furthermore, discrete zones of groundwater upwelling and associated ice blistering (raised humps in the aufeis surface) indicated thermal coupling during winter between the aufeis surface and the unfrozen, water-saturated sediments below (Fig. 14). These findings indicate that the Kuparuk aufeis-spring system maintains a significant and dynamic volume of perennially saturated sediments beneath several meters of frozen sediments during winter which presumably supports groundwater fauna (Terry et al. 2020).

Invertebrate Groundwater Community Beneath Aufeis

The second goal of the research was to look for an active year-round faunal community in the groundwater beneath the aufeis.  To set up the collection system (Huryn et al. 2021), 50 plastic tubes of 3.5 cm diameter, called wells, were driven into the sediment of the ~40 hectare aufeis field in mid-August 2016, using a gas-powered impact driver originally developed to set fence posts. Holes were drilled in the bottom 20 cm of each well to allow movement of water and invertebrates into the well.   The resulting depth of the wells averaged 68.5 cm (range = 37 – 92 cm).  Sampling for invertebrates consisted of pumping a known volume of water (~10.9 L) into a graduated bucket using a hand-operated pump and then filtering the sample through a 250-µm sieve.  Aquatic invertebrates inhabiting surface habitats were also sampled.   These efforts showed that the Kuparuk aufeis field does indeed provide subsurface habitat for numerous freshwater invertebrates that differed from the surface invertebrates. The subsurface diversity is likely enabled by the relatively high porosity of the subsurface sediments combined with a high level of connectivity between pore spaces. This was the first demonstration of a groundwater invertebrate fauna in a region of continuous permafrost (Huryn et al. 2021).  In the Kuparuk collections, the number of invertebrate taxa from wells (49 ± 5) and surface habitats (43 ± 7 taxa) were similar, which was surprising given the lower richness in subsurface habitats in large, riverine gravel-aquifer systems elsewhere.  In fact, our analyses indicated that wells had consistently more species (e.g., ~15 taxa) for a given cumulative community-level abundance than surface samples. This may be explained by greater variability of subsurface habitats (e.g., upwelling and downwelling zones), that likely contributed to higher species turnover among habitat patches compared with surface sediments.

Visiting Galbraith Spring: The Only Spring Along the Northern Dalton Highway

Galbraith Spring is the only spring stream – aufeis complex in the vicinity of the Toolik Field Station accessible by road; it lies near the Galbraith Lake Campground at the end of the 4.3-mile-long airstrip access road beginning near Mile Marker 275 of the Dalton Highway. An aufeis (68.451768º, -149.460027 º) will be visible southeast of the campground through mid-summer depending on meteorological condition. This aufeis results from the fusion of two bodies of overflow-ice. The northern portion is produced by the upwelling of water from the deep gravel layer beneath the channel of a mountain stream that enters the Atigun River floodplain from the west. This stream carries meltwater from the large cirque glacier that is visible southeast of the access road near the airstrip. The southern portion is produced by Galbraith Spring, a tundra spring that flows along the base of the low bluffs directly south of the campground. Although its water temperature may cool to almost 0oC and cap ice covers most of its length during winter, this spring stream flows year-round. During summer, this stream can be easily waded during the morning and early afternoon, but discharge may increase noticeably later in the afternoon as rising temperatures accelerate thawing of the glacier. Keep this in mind when exploring the spring. The spring stream itself is identified by the abundant aquatic mosses that cover its bottom. It provides habitat for a land-locked population of Dolly Varden char, immature burbot, abundant populations of the stonefly Arcynopteryx dichroa and the caddisfly Apatania zonella, all spring-stream specialists in arctic Alaska.  By following the spring-stream downstream, one reaches a wide gravel plain into which the water of the spring percolates and upon which the aufeis is formed during winter.  While exploring the aufeis be sure to note areas where stones and gravel are coated with powdery white deposits of calcium carbonate that is released as water evaporates from the ice layer.  These deposits were dissolved from limestone upstream and then transported to the aufeis by ground water.  Also note the reddish sediment deposited near the margins of the mountain stream.  This is glacial flour carried by the stream from the cirque glacier upstream. A second aufeis (68.471505, -149.657249) is accessible from this general location. It is in a mountain valley directly west of the northern end of the airstrip and is approached using the road to a gravel quarry.  This aufeis is constrained by cliffs and may exceed 3 m in thickness.  The volume of the groundwater reservoir that forms this aufeis appears to be vary from year-to-year as the ice layer does not form every winter.

Ecosystem Role of an arctic spring: Now and in the next century

Most of attention given to aufeis has focused on their physical hydrology (Yoshikawa et al. 2007); so far little is known about the ecology of aufeis fields.  It has been suggested that aufeis function as oases during summer by providing meltwater to downstream habitats that otherwise depend on precipitation and thawing of the active layer (Sokolov 1991), that they provide seasonal habitat for fishes and mammals (Sandstrom 1995, Gill and Kershaw 1979), and that they provide a form of disturbance that maintains characteristic plant communities (Alekseyev 2015).  Before these recent studies, little was known about the enormous subsurface habitat of unfrozen sediments maintained by aufeis or about the extensive ecosystems existing in these unfrozen regions.

Arctic spring streams and aufeis are closely connected and when considering the ecosystem role of an arctic spring, the always present aufeis habitat downstream should also be studied.  In recent years there has been a lot of progress in understanding the ecosystems created; this understanding is included in this chapter.  However, the ecological character of spring streams and the aufeis will probably be affected by climate change in the Arctic where temperatures are rising rapidly (Chapin et al. 2006a, Overland et al. 2015).  Although major aufeis will surely continue to form during winter, even given anticipated winter warming (Cherry et al. 2014), the persistence of ice during the summer thaw will likely decline (Pavelsky & Zarnetske 2017), which will affect the seasonality of flow of receiving aquifers, streams, and rivers.

Perhaps more significant to both spring and aufeis ecosystems are the effects of climate change on patterns of precipitation that recharge the aquifers that supply water for spring and aufeis habitats.  The source of water recharging these aquifers on the North Slope of Alaska is not well understood (Hall & Roswell 1981, Kane et al. 2013), but it is likely that spring stream—aufeis ecosystems will vary in their hydrological responses to changing patterns of precipitation ranging from transient (local aquifer is depleted and aufeis fails to form) to stable (aquifer is maintained) (Cartwright et al. 2020), depending on alterations in recharge patterns. One major question is the lag time before these ecosystems respond, the turnover time for the relatively deep Brooks Range aquifers supplying water to them may be as long as 1000 – 1500 years (Kane et al. 2013) (Fig. 8). This argument suggests that a hydrologic response to climate changes occurring within the next 100 years is unlikely; this is unlike the relatively rapid responses of some European springs to warming trends (Jyväsjärvi et al. 2015).  Nevertheless, under scenarios that include warming and increased summer drying for the Arctic (ACIA 2005, Chapin et al. 2006a, 2006b), multiple emerging roles for spring stream ecosystems and the groundwater communities maintained by aufeis can be envisioned.  These roles include their potential as sources of colonizers if both surfaces with year-round flowing water habitats and groundwater habitats become more widespread due to winter warming. The potential for hydrologically stable spring stream–aufeis complexes to function as refuges in the event of widespread summer drying is another possibility.


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