The Eastern Bering Sea Upper Continental Slope Groundfish Survey: a New Time Series

The Alaska Fisheries Science Center (AFSC) has begun a renewed bottom trawl groundfish survey along the upper continental slope (200-1200 m depth) of the eastern Bering Sea (EBS). In the year 2000 a new time series was initiated which utilized the current AFSC trawling mensuration technologies, oceanographic tools and sampling standardizations as well as the latest taxonomic species recognition and identification guides. The new biennial series has been conducted in 2000, 2002, 2004, 2008 and 2010. The main focus is obtaining distribution, abundance, size composition and age structures of commercially and ecologically important groundfish and invertebrates species. Since 2000 taxonomists at the AFSC have recognized 9 fish species new to science; 30 fish species that are newly found in the EBS, and an additional 24 species of dubious status newly confirmed as part of the EBS slope fauna. The new time series survey has supported greater than 60 ancillary scientific projects from researchers within the Alaska Fisheries Science Center and outside agencies and universities. Time series analysis of catch data suggests a faunal change since the late 1970s with a shift from a more diverse fish ecosystem to one that is dominated by grenadiers, Deep-water surveys are an important tool to monitor fish populations in an otherwise rarely sampled ecosystem.