States spend millions on inland habitat restoration for endangered salmon of the Pacific Northwest, and scientists readily study their dwindling returns to local rivers and streams. But exactly what happens when these fish are out at sea is still shrouded in mystery.
A major scientific expedition launching Tuesday might change that. The Canadian research vessel Shimada will leave Port Angeles and join other ships from Canada and Russia on a three-month mission, covering four zones of the Pacific Ocean.
U.S. Fisheries biologist Laurie Weitkamp, a chief scientist with the National Oceanic and Atmospheric Administration, is one of about 60 researchers taking part. She says most of a salmon’s life cycle is spent out in the ocean, but it’s the phase we know the least about.
“When salmon … leave coastal areas and head out into the high seas, they more or less enter a black box,” Weitkamp says.
“We don't really understand where they are, what they're doing, how much prey is available to them, competitors, et cetera.”
And she says, it’s the hardest phase to study, with the fish spread out over huge distances in often challenging weather, especially in winter.
But she says new techniques using DNA sampling can reveal exactly where a fish is from, using just a tiny fin clip.
“So for the first time ever, especially with all these ships out there covering this huge area, we'll be able to say exactly where stocks are distributed, how they're distributed across the North Pacific, which is really, really valuable,” she says.
Valuable because it can help answer questions that the changing climate is raising about availability of prey and other effects of warmer water on salmon and steelhead distribution.
“Even if you're not out there actively sampling, if you see something like a heat wave, you can say, ‘Yes, my stock is probably in the middle of that’ or ‘No, my stock isn't there,’ " Weitkamp says.
The research organization International Year of the Salmon put the expedition together, working under a treaty with the United States, Canada, Japan, South Korea and Russia.
Pacific region director Mark Saunders says this is probably the boldest, most expansive survey of salmon and the oceanography of the open ocean in the North Pacific. He estimates its cost at about $10 million.
He says the impacts of climate change on salmon are severe — and they’re showing up throughout the northern hemisphere.
“So the timing is really now, to begin to understand this and the complexity of the questions,” Saunders says. “It's not something that just one country can take on.”
Once it’s up and running, the mission will have regular updates on its progress, with photos and video from the field, at its website, yearofthesalmon.org.
A symposium in October will present initial analysis of the mission’s findings.
