Surveys find more pollock midwater, fewer near ocean bottom

Kayla Desroches/KMXT

The current pollock stock is looking strong according to NOAA’s winter midwater surveys, but that’s not consistent with summer bottom trawl surveys.

Representatives presented their most recent data at Kodiak’s commercial fisheries trade show, ComFish, Saturday.

Fisheries biologist Darin Jones said the winter surveys found plenty of the fish spawned in 2012.

“They’re one of the largest year classes that we’ve seen since the 80s when these surveys started, so that is a very good trend for the fishery.”

He said the 2012 year class is reproducing at a steady rate, and while they’re seeing more fish than average, they’re also seeing a smaller distribution of ages.

“There was a few that were spawned in 2016, so there’s a few 2-year-olds out there, but virtually no threes, fours or fives that we’ve seen in our surveys. So, there’s a lot of 6-year-olds, a lot of 1-year-olds, some 2-year-olds this year.”

Fisheries Biologist Kresimir Williams said it’s encouraging to see those young fish from 2017 because it’s not always a certainty that they’ll survive into the next year.

At the same time, summer surveys show fewer numbers of pollock at the bottom of the ocean, which gives managers pause.

“We had that sort of difference between the bottom trawl survey, which is this really long-time series, and it’s showing a decline in pollock, and our survey is showing an increase, and when those two surveys diverge, that doesn’t happen very often. Usually they track each other, they go up and down together, so when the modelers see them diverge like that, they get concerned. They’re like, well, something’s different, something’s changing.

Williams said they would need more data to figure out why the pollock are displacing to shallower depths.