As Salmon And Cod Decline Off Alaska, Opalescent Squid Arrive In Waters Once Too Cold For Them
im Schramek, a retired GIS analyst and hydrologist with the U.S. Forest Service, has been fishing recreationally outside the small Alaskan town of Petersburg for 40 years, but in the last few, things have taken a turn for the worst. Though scientists haven’t yet nailed down the cause, populations of valuable species like king salmon and Pacific grey cod, Schramek says, have fallen to as little as one-tenth of even their 2015 levels. With those populations at historic lows, the Alaska Department of Fish and Game now bans their catch during parts of their historical fishing season.
he bright spot, however, is a small, color-changing squid.
Opalescents, also known as market squid (Doryteuthis opalescens), are showing up in these waters, which were previously considered too cold for them, according to Michael Navarro, an assistant professor of marine fisheries at the University of Alaska Southeast in Juneau. And Schramek and his fellow fishermen are taking note. “I’ve been alongside a [fishing boat] tender the last couple summers when I didn’t have any squid jigging stuff, and they had their boat really lit up,” Schramek says, referring to the luminescent lures used to attract squid. “Lots of lights in the water — just up and down the water column.” While the squid are nowhere near as valuable as king salmon, they’re comparable to the per-pound price of Pacific cod — meaning squid could become a lifeline for fishermen during a time when Earth’s oceans face warming temperatures.
While fish that have traditionally been found in the waters off of Petersburg might struggle to shift northward — particularly salmon, which must breed in rivers that don’t divert easily — “in principle the others can just move with the climate,” says Daniel Pauly, a fisheries expert at the University of British Columbia. In a 2014 article published in the journal Progress in Oceanography — and in many subsequent papers — Pauly and his colleague William Cheung note that a rise of just a fraction of a degree centigrade in ocean temperatures is enough to shift marine habitats north by dozens of miles. The general consensus among climate scientists is that ocean temperatures will rise another degree or more by 2050, exacerbating the habitat changes.
EDIT
https://undark.org/article/market-squid-alaska-climate-change/