Arctic grayling were caught in the Kuparuk River using unbarbed hooks with hook and line gear. The fish were tagged with different types of tags, depending on the year of caputre. Originally, Floy tags were used, but recently, PIT tags have been used. If the fish were caught a second time during a single summer, the growth was determined based on the change in length and weight from the first capture to the second. The fish were kept in the same reach as original capture through the use of fish weirs blocking movement.

When grayling were caught, the station was recorded. In 1983, phosphorus addition through dripping began at the site designated as 0.0k. Stations downstream of 0.0k have positive numbers and upstream have negative numbers. The reach upstream of the phosphorus addition has remained the reference reach for the duration of this dataset. Downstream of the original phosphorus addition was the fertilized reach. In 1985, the phosphorus dripper moved to 0.59k, creating a recovery reach from 0.0k to 0.59k. In 1996, the dripper was moved downstream to 1.4k, creating a recovery reach between 0.6k and 1.39k. The historic recovery reach from 0k to 0.59k had not been fertilzed for 11 years, so it was then considered part of the reference reach after 1996. Reach information can be found in data for specific time periods.

Data is available for years 1896, and 1988 to 2003.
Arctic LTER Streams Protocol, updated 2010 by EBS

http://ecosystems.mbl.edu/ARC/streams/protocol2.html