And, they’re off! This season’s first batch of salmon fry will soon be entering the open ocean with lots of food and plenty of predators. Some will be back in a few years to spawn. Others will be back as soon as next year after they swim a giant counterclockwise circle of the North Pacific.
But fisheries biologists wonder about one salmon run that just left a Juneau stream earlier than ever before. And they’re curious about how a new, large mass of warm ocean water will affect those young salmon as they grow.
“It’s good to separate them because the little fish don’t like being in with the big fish.”
John Joyce just counted one more pink salmon passing through the weir at Auke Creek, located north of downtown Juneau. The tiny, inch-long fry is a straggler. Most of his 14,000 siblings are already hanging out in Auke Bay before heading out into the open ocean.
“There’s physical characteristics on the shape of their fins and the shape of their eyes, and their coloration. You have the ability to tell them apart. But it does take some time to get your eye educated because we do rely on that to separate out the species.”
Joyce, a fisheries research biologist with the National Oceanic and Atmospheric Administration, says – based on data collected over the last 35 years — Auke Creek’s out migration of pink fry is one of the lowest on record and two weeks ahead of schedule. Joyce suspects that recent mild winters prompted by climate change are behind the subtle, yet steady trend of earlier pink migrations.
But he’s not so sure about another relatively new phenomenon…
“But you’re not willing to say that The Blob was cause of it?” “No, no, nah… <mock fear> It’s The Blob! It’s The Blob!”
That’s the name coined by Washington state climatologist Nicholas Bond for a huge, evolving, moving mass of warm ocean water in the eastern North Pacific Ocean. He says they’re not quick sure how it will affect Alaska salmon.
“We do know that in 2014, because of that warm water, that the base of the food web production of phytoplankton that supports the whole food web was reduced because that warm water served to isolate the near surface waters from the more-nutrient rich water below. ”
Bond says The Blob is bad news for Lower 48 salmon since the warmer water attracts less nutritious prey species.
Over the last two winters, The Blob has moved and stretched out along the coast of Western U-S from California to the Gulf of Alaska. That’s right in the counterclockwise path of pink salmon coming home this year. How will they be affected? For the answer, Joyce refers to a prognosticating colleague at NOAA’s Ted Stevens Marine Research Institute.
“Joestradamus, Joestradamus.”
Research fisheries biologist Joe Orsi says they’re cautiously optimistic about a strong run of about 55 million fish this year. Those pinks will be the children of 2013’s big return. But they’ll be running through The Blob as they approach the Oregon shore and start heading north.
“The implications of climate change on fish species is important, for them all. Salmon will be first ones reporting back to us if there’s a problem out there. We’ll know this year if the warm blob of 2014 caused something to terrible to happen to the pink salmon because they’re just basically not going to return in high numbers this year.”
Pink salmon or humpies usually don’t get a lot of love. They’re physically smaller than the other four salmon species. But they’re still a major part of the Southeast Alaska commercial salmon industry, worth 124-million dollars during 2013’s blockbuster season. They’re also important ecologically, with the fry serving as food for their larger Chinook and Coho cousins. Bears, eagles, and marine mammals – including whales – will go for the adult humpies.
Orsi also wonders about those Auke Creek pink fry heading out early this spring. He uses the term…
“…Mismatch….”
…to describe how the out-of-sync fry may wander around and wait for their zooplankton breakfast to show up.
“If they can’t grow, they spend more time in the near shore, the littoral zone near the beach when they’re small. They’re more vulnerable to predators, both avian and fish predators. They need to grow to a certain size before they actually start moving off shore and migrate out into open waters.”
And how will The Blob affect those out migrating, still developing pinks? Orsi says salmon will grow faster in slightly warmer water, but they’ll also need more food. And the warmer water could attract other unusual species and potential predators like blue shark and thresher shark, and Humboldt squid.
Back at the Auke Creek weir, John Joyce says they won’t be getting any quick and easy answers about the effects of The Blob. They’ll also have to consider other ecosystem factors.
“It’s all very interesting how these populations can optimize their productivity over time, be successful, and continue to deal with changing environmental conditions. They have the ability to adapt and to change their behavior. At what point is it too much or too little?”
There may be a few clues with the first pink returns from the 2013 brood year. That’s coming up in August.
Matt Miller is a reporter at KTOO in Juneau.
