2025 Winter Acoustic-Trawl Pre-spawning Pollock Surveys in the Gulf of Alaska

What is the research objective?

The objective is to estimate the abundance and distribution of pre-spawning walleye pollock in winter spawning regions of the Gulf of Alaska, using acoustics and targeted trawling on acoustic backscatter, to inform fish stock assessment models and catch allocation.

Where is the research being conducted?

This survey covers several walleye pollock main spawning grounds. Historically, most of these efforts have been focused on the Shelikof Strait area, which has been surveyed annually since 1981 except in 1982, 1999, and 2011. The Shumagin Islands area, Pavlof Bay, Morzhovoi Bay, Sanak Trough, Chirikof Shelf Break, Marmot Bay, Kenai Bays, and Prince WIlliam Sound have been surveyed intermittently over the past 2-3 decades.

Who is conducting the research?

Scientists from the Alaska Fisheries Science Center’s Midwater Assessment and Conservation Engineering Program will work aboard the NOAA Ship Oscar Dyson.

Why are the data important? How will data be used?

Data from the acoustic-trawl surveys provide estimates of pre-spawning pollock numbers and biomass by length and age, environmental observations, and observations on other species in the water column. These are key ingredients and environmental indicators for the Gulf of Alaska Stock Assessment and Fishery Evaluation report and the Gulf of Alaska Ecosystem Status Report provided by Gulf of Alaska Plan Teams to the North Pacific Fishery Management Council for science-based management of the pollock fishery.