ANCHORAGE — State researchers looking for answers to Alaska’s diminishing king salmon returns were urged Tuesday to take a look at the critical days after smolt leave fresh water and to closely examine how humans may affect salmon in marine waters.
“The two leading hypotheses for things that might cause declines of chinook salmon in the ocean are climate change and fishing,” said retired University of Washington fisheries biologist Kate Myers.
She was part of a panel that spoke at the state’s two-day Alaska Chinook Salmon Symposium, organized to identify gaps in a draft research plan that Gov. Sean Parnell ordered up after a summer of dismal king salmon returns.
Alaska commercial fisheries chief scientist Erik Volk said researchers have an idea of how to approach the problem but want to hear from federal and university experts. They also want to hear from fishermen who depend on the resource but were turned away from fishing to make sure there were enough spawning kings to lay eggs for the next generation of fish.
“What are those information needs and how are we going to fill them?” said Volk, who is overseeing research with his counterpart in sport fisheries, Bob Clark.
Salmon returns since a peak in 2006 have declined in most watersheds the state monitors. The U.S. Department of Commerce in September declared king salmon fisheries failures in Cook Inlet plus the Yukon and Kuskokwim rivers, making commercial fishermen eligible for disaster relief.
The reason for the poor returns is unknown but researchers suspect ocean factors.
Myers echoed other speakers in calling for studies of salmon during their critical first year in saltwater, when they must grow enough to survive an ocean winter.
“That is a huge information gap and I would encourage a focus of research on nearshore habitats,” she said.
Focusing studies on human effects, she said, might result in progress in learning about the open-ocean ecology of king salmon. She urged researchers to look at climate change and ocean acidification plus the effects of industrial fishing.
“Not really focusing on the bycatch mortality but focusing more on the ecological interactions,” she said.
Marine pollution, she said, “is one of those invisible things that nobody’s really wanted to look at.”
The interaction between wild king salmon and hatchery fish, including pink salmon, also has not been studied.
“This is a huge area and people have avoided thinking about it,” she said. Meanwhile, there are plans for dramatic increases in hatchery production both in the Gulf of Alaska and on the Russian side, she said.
The state hopes to have a king salmon research plan in place by early December, Volk said.
The framework is a focused look at a dozen king salmon drainages representative of the diverse life history, genetic attributes and ecology of the state’s king salmon populations.
The 12 rivers include the Yukon, Kuskokwim, Kenai, Susitna, Copper, Unuk, Stikine, Taku, Chilkat, Karluk, Chignik and the Nushugak.
“We’re probably going to pitch quite a bit of work,” he said.