Odd visitors found off Oregon Coast
Over the past five months, Bill Thompson has found a dozen warm-water species of copepods — tiny, energy-rich organisms at the base of the marine food chain — during his biweekly surveys off the Oregon Coast.
The senior scientist for the National Marine Fisheries Service at Newport said finding the out-of-place species is like looking out your window and seeing parrots and macaws instead of robins and finches.
“These are tropical species that never get this far north — never,” he said.
The presence of the tropical copepods, which are smaller, thinner and less abundant than the types of copepods Thompson has been collecting and counting for more than 20 years, is not a good thing. It is one of many indicators the ocean has entered a warm phase, with much less of the cold-water upwellings that have driven healthy returns of salmon and steelhead over the past few years.
Normal sea churning lifts cold, nutrient-rich water from its depths to the surface, where it feeds copepods, which in turn feed the types of fish that salmon and steelhead eat to grow big and fat before they return to fresh water to spawn.
Now an unusual blob of warm water that formed off the Gulf of Alaska and another in the eastern Pacific have merged and inundated the West Coast of the United States and the coast of British Columbia. The warm water has less upwelling and fewer copepods.
“What it means is there is not much out there to eat, and that can’t be good for anybody — salmon included,” Thompson said. “The whole food chain, I would guess, is going to be impacted. The base in the food chain is very low in numbers and very low in mass.”
The National Oceanic Atmospheric Administration released a report Tuesday outlining the changing climate patterns in the coastal Pacific Ocean known as the California Current. The changes are likely responsible for a rash of malnourished sea lion pups that have washed up on California beaches over the past few weeks. Scientists have also found dying and emaciated sea birds, called Cassin’s auklets, that could be linked to changes in sea surface temperatures and currents.
It’s not unusual to see changes in currents and temperatures. Scientists have long documented climate phenomenons such as the El Nino weather pattern that can lead to warmer and wetter winters in the Pacific Northwest and a longer-term pattern called the Pacific Decadal Oscillation.
Each are marked by warmer sea surface temperatures, less upwelling and poor foraging conditions for fish and marine mammals. But scientists are scratching their heads over the conditions they are seeing this spring.
For example, Chris Harvey, a fisheries biologist with the Northwest Fisheries Science Center in Seattle, said the warm blob off Alaska that is sending currents of warm water down the coasts of Washington and Oregon is unprecedented.
“As far as climate scientists know, it could be a weird aberration or it could very well be something that could stick around for a while,” he said.
Or as Northwest Fisheries Science Center Director John Stien put it, “We’re seeing some major environmental shifts taking place that could affect the ecosystem for years to come.”
Nate Mantua, another NOAA scientist, said the conditions are so unusual that he believes they won’t be long-lasting. But if they do persist into next year, it could lead to another strange winter with low snow accumulation in much of the Pacific Northwest and continued drought in California.
“If those conditions in the tropics stay the same, maybe that is going to favor another crazy winter,” he said.
The “crazy winter,” combined with the warmer, less-productive ocean, is lining up a one-two punch for salmon and steelhead. The winter produced meager snowpacks that will melt faster and lead to warmer temperatures and lower flows in the streams where salmon spawn and their offspring spend the first parts of their lives.
Smolts that migrate to the ocean this spring won’t have the benefit of the high spring flows they depend on to flush them seaward. Once they reach the ocean, they won’t find much to eat.
“That doesn’t bode well for early marine growth and early marine survival for Northwest salmon and also California salmon that go to the sea this year,” Mantua said.
Scientists are on alert and monitoring conditions and trying to discern how long they might persist. Among all the doom and gloom, Thompson said there could be sliver of hope.
Over the past few weeks, there have been strong north winds off the coasts of Oregon and Washington, another unusual pattern. If they persist, they could push the warm water off shore and lead to more upwelling.
“But they have to keep blowing,” he said. “We don’t know if they will do that.”
Eric Barker may be contacted at email@example.com or 208-848-2273.