Stock Assessment of Buskin River Coho Salmon, 2011-2013
Author: Tyler Polum
Publisher:
Published: 2017
Total Pages: 45
ISBN-13:
DOWNLOAD EBOOKThe Alaska Department of Fish and Game (ADF&G) Division of Sport Fish (SF) has assessed the annual runs of coho salmon (Oncorhynchus kisutch) to the Buskin River on Kodiak Island since 1985 via a weir on the Buskin River; the weir was moved to its current location in 1989. This report presents weir counts, harvest, and age-composition data collected between 2011 and 2013 as well as a spawner?recruit analysis. In 2011, the Buskin River weir count was 6,026 coho salmon; the estimated sport harvest was 3,640; the reported subsistence harvest was 287; and the commercial harvest was 197 coho salmon. Age-2.1 fish composed 72% of the total run and the male to female ratio was 1.1:1. Estimated escapement was 5,298 coho salmon. In 2012, the weir count was 5,291 coho salmon; the estimated sport harvest was 1,926; the reported subsistence harvest was 984; and the commercial harvest was 10. Age-2.1 fish composed 92% of the total run and the male to female ratio was 5.8:1. Estimated escapement was 4,906 coho salmon. In 2013, the estimated weir count was 5,959 coho salmon; the estimated sport harvest was 5,294; the reported subsistence harvest was 611; and the commercial harvest was 40. Age-2.1 fish composed 82% of the escapement and the male to female ratio was 0.93:1. Estimated escapement was 4,900 coho salmon. A full probability spawner?recruit analysis of all relevant data gave an estimated spawning escapement at maximum sustainable yield (MSY) of approximately 7,300 coho salmon (90% credibility interval of 5,140?12,000). Assuming a 10-year average sport harvest, the inriver run estimated for MSY is about 8,150 coho salmon and the estimated exploitation rate at MSY is 40%.