Lake Clark Sockeye Salmon Escapement and Population Monitoring, 2008 - 2011 PDF Download

Author: Daniel B. Young
Publisher:
ISBN:
Category : Escapement (Fisheries)
Languages : en
Pages : 33

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Book Description
The Lake Clark sockeye salmon run, a key component of the Kvichak River run, supports important Federal subsistence fisheries. This report describes findings from a salmon counting tower project conducted on the Newhalen River from 2008 -- 2011. Specific objectives were to 1) estimate sockeye salmon escapement to Lake Clark and 2) determine age, sex, and length of the Lake Clark escapement. Estimates of escapement were made at river kilometer 36 on the Newhalen River using the same tower site and protocols used in previous studies. In 2009, turbid water conditions compromised counts after July 22 and escapement after this date was estimated using historical count data. Sockeye salmon age and size were determined from otoliths collected from the Newhalen River subsistence fishery and from post-spawning fish at Lake Clark spawning habitats. During 2008 -- 2011, total Lake Clark escapement averaged 316,496 salmon and ranged from a low of 210,372 salmon in 2009 to a high of 472,962 salmon in 2008. The 2008 -- 2011 mean escapement to Lake Clark was 22% lower than the 2000 -- 2007 mean of 403,991 and 72% lower than the mean escapement of 1,135,464 during 1980 -- 1984. During the study period, the Lake Clark escapement comprised, on average, 11% of the total Kvichak River escapement, about 5% less than observed in the 1980s and 8% less than observed during the period from 2000 -- 2007. The estimated mid-point of the run was similar to previous years in 2008 and 2011 but was likely earlier than average in 2009 and 10 days later than average in 2010. The age composition of sampled fish from Lake Clark was predominately age 1.3 (48- 65%), followed by age 1.2 (22-34%), age 2.2 (1-21%), and age 2.3 (0-9%).