Aquaculture for all

Alaska Fish Factor: New Research Blames Too Many Pinks for Slow Sockeye Growth

Salmonids Nutrition Sustainability +8 more

US - Alaskan salmon producers are not buying the presumption that growing numbers of pinks are eating too much food in the ocean, causing sockeye salmon to grow slower and smaller.

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That’s the claim of a new study by Seattle and British Columbia researchers, who say the race for food ultimately affects sockeye abundance and survival.

“Our data sets extend up to 55 years each. In terms of looking at productivity or survival of salmon, they’ve included 36 sockeye populations,” said Greg Ruggerone, a researcher at Natural Resources Consultants in Seattle and study co-author.

The project was aimed originally at finding causes for declining sockeye runs at British Columbia’s Fraser River in 2009, but has since broadened to include the whole North Pacific.

“Hatcheries in Alaska, Russia and Japan have continued to increase production of salmon, primarily chums and pinks. Up to five billion hatchery salmon are released into the Pacific Ocean each year,” Ruggerone said in a phone interview. “Concerns have been raised at fisheries conferences that the release of so many salmon is impacting the growth and survival of wild stocks, including salmon originating thousands of miles from those hatcheries.”

Ruggerone also has published similar food competition studies for Bristol Bay. So how does he account for big back to back red runs to the Bay?

“Because there are relatively few pinks in Western Alaska compared to Russia, the sockeyes most likely encountered favorable conditions in their early marine life that supported these large runs,” Ruggerone said. “But that doesn’t mean the pinks don’t have an adverse effect on them during the second or third year at sea. It’s just overshadowed by very favorable conditions earlier.”

The report recommends a Pacific Rim approach to managing salmon resources, and more immediately, capping hatchery production.

“Do you think we can control Russia?” quipped said Steve Reifenstuhl, longtime general manager at Northern Southeast Regional Aquaculture in Sitka. “If there was a cap, Russia and Japan would quickly move to fill any void,”

Reifenstuhl called the food competition claims “alarmist,” and cited several peer reviewed reports that refute Ruggerone’s claims.

“My reaction is that he is speculating that there is a correlation, and that it is causative,” Reifenstuhl said. “I would disagree that it’s causative.”

He pointed out that Alaska’s largest pink salmon runs occur at the Panhandle and over 95 percent are wild stocks.

“Certainly increased competition can decrease salmon body size, as we’ve often seen in big runs, but it doesn’t mean more will die,” he added. “Where 10 to 90 percent of the sockeyes do die is in near shore waters, before they even head out to sea.”

Kodiak hatchery operators agree.

“If the ocean’s carrying capacity has reached its limit, we wouldn’t be seeing returns like we had in 2013 for pink salmon, which also wasn’t a bad sockeye year,” said Tina Fairbanks, executive director for the Kodiak Regional Aquaculture Association, which operates two hatcheries. “Look, too, at the Bristol Bay forecast for 2015, it’s huge, and it’s the same for Southeast pinks. I don’t believe it is a valid argument.”

“I don’t see how we are a primary contributor on the grand scale,” said Trent Dodson, KRAA Production and Operations Manager.

He also pointed out that Ruggerone’s Alaska pink salmon hatchery numbers are way off. Whereas his report claims that 1.4 billion hatchery produced pink salmon are released into the ocean annually, primarily in Prince William Sound and at Kodiak, Dodson said Kodiak releases average 144 million juvenile pinks each year. State data show the Prince William Sound pink salmon release for 2014 was 672 million fish.

The report titled "Productivity and life history of sockeye salmon in relation to competition with pink and sockeye salmon in the North Pacific Ocean” was featured in the March Canadian Journal of Fisheries and Aquatic Sciences.

Capital celebration! The 6th annual Juneau Maritime Festival celebrates fishing and every other industry that moves upon the water, and makes its home in the state capital.

“Just the seafood industry alone – there are about 800 Juneau residents who make their living from ocean harvests. And we have the Coast Guard and NOAA, our marine transportation, cruise ships, just a myriad of other professions that are linked to the sea,” said Brian Holst, executive director of the Juneau Economic Development Council, host of the event.

Several thousand people always attend the Saturday event, Holst said, which starts with the arrival of two canoes from the One People Canoe Society and a traditional Native welcoming ceremony.

Events include a Coast Guard rescue in the channel, onboard vessel visits and a fillet contest. The date is May 8.

Bycatch begone -Alaskans have had it with high rates of halibut bycatch in the Bering Sea and a push is afoot to slash it by half. At issue is six million pounds of halibut allowed as bycatch in the multi-billion pound Bering Sea flatfish fisheries, a rate that hasn’t been changed for 20 years. At the same time, declining halibut stocks statewide have seen managers cut catches by commercial, sport and subsistence users by 70 percent.

The North Pacific Fishery Management Council is set to make a decision at its meeting in June and advocates are really putting on the heat. Last week in a strongly worded letter, 16 Alaskan groups and communities urged Alaska’s Congressional reps to push for the 50 percent bycatch cut, saying “conservation of the halibut stock is riding solely on the backs of the halibut fishermen.”

That follows a similar action in April by a dozen Alaska legislators who urged the NPFMC to make the 50 percent cut as soon as possible.

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