Genetics study confirms fish in OPH bound for Bristol Bay

Mar 10, 2016

A recent study said that no matter how far from shore an Area M fisherman fishes, the majority of his sockeye catch in the Outer Port Heiden section is likely to be headed to Bristol Bay.

Credit Courtesy Alaska Department of Fish and Game

A recent study concluded that – as expected - most of the sockeye swimming through the North Alaska Peninsula’s Outer Port Heiden section are on their way back to Bristol Bay. But that conclusion didn’t lead to the changes Bristol Bay stakeholders were hoping for at the state Board of Fisheries’ Alaska Peninsula meeting last month.

Bristol Bay Economic Development Corporation funded the study. CEO Norm Van Vactor said it confirmed the results of a prior study, called the Western Alaska Salmon Stock Identification Program.

“It was a very complete and a very robust study, and it demonstrated very, very clearly and reinforced WASSIP that at the end of the day, on average, close to 90 percent of the fish in that area were Bristol bay Bound, and also demonstrated very clearly that as you move farther north from Ilnik through Outer port Heiden and up, that that percentage increased even further,” he said.

The University of Washington’s Alaska Salmon Program conducted the study. Research Scientist Chris Boatwright said the study was similar to WASSIP, and used the same stock of origin markers as that prior study did.

“We are catching sockeye that are migrating through the Outer Port Heiden management section and the Ilnik management section and then we are using genetic stock identification to identify those sockeye back to stock of origin,” Boatwright said. “In this case, most of those stocks of origin were either Bristol Bay stocks or they were North Peninsula stocks.”

According to the study, Bristol Bay stocks contributed 93 percent of the estimates from the Outer Port Heiden section in 2014, and 83 percent in 2015. For the Ilnik section, Bristol Bay stocks were 56 percent in 2015.

The state-waters salmon fishery extends to three miles offshore in the Outer Port Heiden section. Boatwright says the project stemmed from a 2013 Board of Fisheries regulation that closed the outer mile and a half, in an attempt to focus the harvest on North Peninsula salmon.

“But there was no real data to assess whether or not that partial area closure was really effective at conservation of any one stock component,” Boatwright said.

So the UW team put together a study that looked at the genetic stock composition in the area open to fishing in Outer Port Heiden, and stock composition in the area closed to fishing in that section, and compared the two, to look at whether the closure had the intended effect.

“And what we found was that there were no stock composition differences between the area open to commercial fishing and the area closed to commercial fishing,” Boatwright said. “So in other words, regardless of whether you are fishing in the closed area or whether you’re fishing in the open area, you are really fishing upon the same stocks. So the closure was not effective at doing what it was intended to do.”

To figure it out, the researchers had a boat use the same commercial fishing gear that is used by North Peninsula fishermen, and used it to catch what they believed was a representative sample of the fish available to catch in both management sections. Samples were sorted and genotyped, matching them to the same reporting groups that were used in the WASSIP study.

After parsing the data, Boatwright said the study found that there wasn’t a difference between the sockeye in the open and closed parts of the section. Area M fishermen are likely to catch mostly Bristol Bay-bound sockeye, no matter how close to shore they’re fishing in the Outer Port Heiden section.

But those results didn’t have the effect that BBEDC was hoping for. At the Alaska Peninsula meeting last month, the Alaska Board of Fisheries opened the whole Outer Port Heiden section, a request that came from Concerned Area M Fishermen, instead of closing it entirely, like Bristol Bay stakeholders were hoping for.