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Bristol Bay Smolt Program
About
BBSRI enumerated sockeye salmon smolts in Bristol Bay from 2008-2019. The goal of the smolt program was to provide annual age-specific estimates of the number of juvenile salmon going to sea in three Bay rivers (Kvichak, Ugashik and Egegik).
These data can be used for pre-season forecasts of adult salmon returns, developing spawning (escapement) goal targets, and characterizing changes over time in freshwater and marine productivity.
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We collaborated with the Alaska Department of Fish and Game (ADF&G), sharing field sites, logistics, and resources. The BBSRI smolt program built upon ADF&G’s ~3 decades of sonar-based smolt research developed in the early 1970s and discontinued in the early 2000s.
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Sonar Technology
From 2006-08, BBSRI and Scientific Fisheries Systems developed a sonar system made up arrays of up to 8 upward-looking sonar pods connected to shore by power and ethernet cables. Sonar pods contained a low-power, custom sounder and a single-beam transducer. We deployed two redundant arrays on each river to make two independent estimates of the hourly, daily, and annual smolt abundance.