Warm water Blob may be sending salmon forecasts awry

Fisheries researchers say the appearance of a warm water anomaly in the northeast Pacific Ocean likely added a new wrinkle into recent predictions of Alaska salmon runs that are used by commercial fishing industry for the upcoming season’s planning. Because of the variability of West Coast salmon populations, a simple cause and effect may be impossible to pin down.

A seiner fishing for salmon off the coast of Raspberry Island in July 2009. (Public domain photo courtesy of NancyHeise)
A seiner fishing for salmon off the coast of Raspberry Island in July 2009. (Public domain photo courtesy of NancyHeise)

Biologists admit they’re still not sure exactly how the warm water Blob is affecting salmon up and down the West Coast.

“The thing that we need to think about is that warm water in Alaska is really different than warm water in California,” said Brian Beckman, a research fishery biologist at National Oceanic and Atmospheric Administration’s Northwest Fisheries Science Center in Seattle.

“Warm water in California can be so warm that it is actually injuring the fish, whereas warm water in Alaska just means that it is abnormally different and maybe the ecosystem is different. But it’s still a comfortable place for fish to be,” Beckman said.

Beckman was one of the organizers of March’s Salmon Ocean Ecology Meeting in Juneau, which featured biologists and researchers from California to Alaska.

Because of differences in the life cycles and migration patterns of the five Pacific Ocean salmon species, Beckman said it’s impossible to immediately determine how The Blob is affecting salmon abundance, run timing, growth, forage habits and complicated predator-prey relationships.

“It’s really hard to talk about salmon runs all across the coast in any one single focus because they all kind of do different things,” said Beckman. “The Blob does not have one specific effect across all salmon stocks.”

Why would any of that information be important? The $414 million answer to that question comes from the Alaska Department of Fish and Game. That’s the dock price paid for all salmon harvested last year. In addition, the McDowell Group of Juneau says Alaska’s salmon fisheries generate $845 million in income for 18,400 direct jobs.

Joe Orsi, fisheries research biologist at NOAA’s Ted Stevens Marine Research Institute at Auke Bay, explained why they research salmon biology, and do modeling or run simulations to predict Alaska salmon abundance, run timing and even size of the fish.

“Basically, you confront the stakeholders and say this is what we think is going to happen, and you interact with the industry people,” Orsi said. “This is when the decisions are made.”

They include decisions by state fisheries managers who plan the timing and length of the openings, the processors which dispatch tenders and hire outside help to work in the plants and the fisherman who must budget his or her expenses and figure out how many deckhands to hire.

Pink salmon, plus an occasional silver and red, congregate in a pool above the Auke Creek weir before spawning. The males will put on displays and fight with other males as part of the competition for mating females which have already started a nest. (Photo by Matt Miller, KTOO - Juneau)
Pink salmon, plus an occasional silver and red, congregate in a pool above the Auke Creek weir before spawning. The males will put on displays and fight with other males as part of the competition for mating females which have already started a nest. (Photo by Matt Miller, KTOO – Juneau)

Orsi said they’re not sure if it was The Blob’s presence in the northeast Pacific that upended their modeling for last year’s salmon runs. Overall, last year’s pink harvest in Southeast Alaska fell well short of predictions with runs in the southern part of the Panhandle doing poorly.

Another big question is whether El Niño or equatorial warming has encouraged other species to wander north.

“Of course, we have unknown ecological impacts of the subtropical fish species that were occurring in the Gulf of Alaska: tuna, sunfish, thresher sharks,” Orsi said. “We don’t know if there’s going to be increased competition or predation as a result of those.”

In order to get a better handle on what is happening, researchers have created a coast wide database that is intended to show how The Blob is affecting various salmon runs. Bryan Burke, research fishery biologist at the Northwest Fisheries Science Center in Seattle, helped design it.

“This could be a good way to summarize when and where did The Blob impact salmon,” Burke said. “The fact is that we don’t know yet because a lot of the salmon that were in The Blob have not returned yet.”

Some of those fish that have not returned yet are mature Copper River reds. Those fish are usually harvested during the very first commercial fishery of the year. It could kick off as soon as mid-May.