Abundance, composition, and emigration of Arctic grayling in the Goodpaster River, 1995-1997

Alternate Titles

• Federal aid in sport fish restoration (Alaska)

Description

Mark-recapture experiments were conducted in the Goodpaster River over a six day period soon after ice-out in early May of 1995 1997 to estimate abundance, composition, and post-spawning emigration of Arctic grayling, Thymallus arcticus. Study area encompassed the lower 70 miles in 1995 and the lower 33 miles in 1996 and 1997. Over the three years, 8,025 Arctic grayling were captured. Estimated abundance of Arctic grayling 230 mm FL in 1995 was 23,194 fish (SE = 3,257) in the 70 mile reach and 13,445 fish (SE = 1,445) in the 33 mile reach. Estimated abundance in 1996 was 25,364 fish (SE = 3,093) 150 mm FL and 12,893 fish 230 mm FL (SE = 1,839) in 1997. In all years, quality-sized and larger fish (270 mm FL) predominated as did the 1990 year class. Age 6 and older fish comprised the majority of yearly age compositions. Relative contribution rates based on tag recoveries of these fish the following July in the Delta Clearwater River ranged from 22% (SE 5%) to 34% (SE 6%) in three length groups over the three years of estimates.

Subjects

Links

• URL