Council scientists back new Gulf of Alaska pollock model as survey mismatch persists

The North Pacific Fishery Management Council's Scientific and Statistical Committee on Wednesday backed a Gulf of Alaska pollock assessment, Model 26A, as its new base model. The assessment's author also brought forward a companion version that links recruitment to ecosystem conditions. The committee asked for more evaluation of that version before December, when catch advice gets set, and a description in November of what it would take to use it for catch advice, though this cycle's advice will still use average recruitment.

The model has fit the summer bottom trawl survey poorly in every survey since 2017, committee members noted. Assessment author Cole Monnahan of NOAA Fisheries said the 2025 survey's very large estimate was driven largely by one to three tows near Unimak Pass. "I don't think there's a simple answer," he said.

Monnahan is testing whether shifts in how much of the stock sits within reach of the bottom trawl net explain the mismatch, a test that requires the summer acoustic survey; that survey was suspended in 2025 and is not planned for 2027. He called a competing explanation, that Bering Sea fish are entering the western Gulf, fairly weak.