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Study: Warmer ocean waters to drive Pacific Northwest fish northward

Local fishing fleets may need to switch to warmer water species like squid, sardines and albacore in the coming decades, according to a recently published study.

Anticipated changes in climate that result in warmer ocean waters will push West Coast fish and other marine life north about 19 miles a decade through 2050, according to a study done by several scientists, including Richard Brodeur, a NOAA Fisheries senior scientist who works at the Northwest Fisheries Science Center’s Newport, Ore., research station. The study was published last fall in the journal Progress in Oceanography.

This northward movement is expected to happen to species like salmon, which have narrower temperature preferences than warmer-water species.

“As the climate warms, the species will follow the conditions they’re adapted to,” said Brodeur in a news release about the study. “We’re going to see more interactions between species and there will be winners and losers that we cannot foresee.”

Local fishermen already are noticing the changes. Pete Granger, a reefnet fishermen at the Lummi Island Wild Co-op, said they’ve noticed sardines and squid moving up north through the California and Oregon waters in recent years. Eventually that could lead to changes in what the local fleets fish for, a move Granger said the fleet is capable of handling.

“The Bellingham fleet is very adaptable,” Granger said, noting fishers were able to adjust when a large number of sardines came into the region around 15 years ago.

Perhaps even more dramatic will be the impact of existing northern marine life as more species shift north. The study expects warm-water species such as thresher sharks and chub mackerel to be more common off the coast of British Columbia and the Gulf of Alaska in the coming years. As a result, current northern predators such as sea lions and seabirds also may need to adjust.

“If their prey moves farther north, they either have to travel farther and expend more energy to get to them, or find something else to eat,” Brodeur said. “It may not happen right away, but we are likely to see that kind of a trend.”

The 2015 fishing season could have its own challenges. Granger is particularly concerned about the low snow pack for this time of year; it’s about half of normal. If it remains low, rivers could be very low in the fall, affecting fish runs.

For the Bellingham commercial fishing fleet, this year is expected to feature a strong pink salmon run. What could thwart local fishing efforts, however, is the blob of warmer water that was parked off the coast of Vancouver Island last spring and summer. That area of water was about 3 degrees Celsius warmer than normal and pushed most of the sockeye salmon Fraser River run around the northern part of Vancouver Island through the Johnstone Strait into Canadian waters. That allowed Canadians to pull in 94 percent of the overall catch, while many local fishers gave up because so few fish entered U.S. waters.

Currently the waters along Washington’s coast are quite warm, said Nick Bond, a research scientist for the University of Washington. One difference from last winter is that the warm anomalies are more prominent near the coast versus offshore.

This area also has had more warm storms coming in from the south this winter, producing less churning and cooling of the upper ocean levels than usual. Bond said a strong consensus of the climate models suggest that the local waters will remain considerably warmer than normal this year.

“(This is) not good news for many elements of the marine ecosystem, particularly the young salmon going to sea this upcoming spring,” Bond said.

Granger said pink salmon typically follow the same route in the Fraser River run, with about half of the run going around the north part of the Vancouver Island while the other half goes around the south end through the Strait of Juan de Fuca. He said it would be a big blow to the local fleet if most of the run goes north for the second straight year, though it’s unclear if pinks would react to warmer waters the same way the sockeye did.

“Our expectation is that it will be a good season,” Granger said.

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