Abundance and Run Timing of Adult Salmon in Henshaw Creek, Kanuti National Wildlife Refuge, Alaska, 2000-2003. Alaska Fisheries Data Series Number 2005-11

摘要

Chinook and summer chum salmon escapement counts assist managers in making decisions during in-season run activity, provide post season evaluation of various management practices, and assist in developing future run projections. From 2000 to 2003 a resistance board weir was used to record escapement information from Chinook and summer chum salmon on Henshaw Creek, within the Koyukuk River drainage, Alaska. The four-year average escapement for Chinook salmon was estimated at 670 fish with a range from 193 in 2000 to 1,091 in 2001. The average median date of passage occurred on July 16. The average Chinook salmon sex ratio was 38 percent females. The proportion of females generally increased as the season progressed in 2000 and 2001, but declined earlier in the run in 2002 and 2003. The 1.4 age class predominated only in 2001, while the 1.3 age class prevailed in the remaining years. The four-year average escapement for summer chum salmon was estimated at 26,458 fish with a range from 21,400 in 2003 to 34,777 in 2001. The average median date of passage occurred on July 19. The average summer chum salmon sex ratio was 57 percent females. The proportion of females increased in a consistent manner as each season progressed. The yearly dominant age class varied between age classes 0.3 and 0.4.