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Drought leaves fish high and dry

Low river flows hurt chinook spawning

By Isabella Breda, The Seattle Times
Published: November 1, 2022, 6:03am

CHEHALIS — As biologist Nick Vanbuskirk drew a knife along the yellowing belly of the carcass of a chinook salmon, hundreds of ripe, translucent orange eggs spilled out into the ankle-high waters of the Newaukum River.

After surviving a stint in the Pacific Ocean, this salmon was met with over 70 miles of warm, shallow river. Along the way, she evaded hungry predators and made it most of the way back to her spawning grounds. But she died before she finished the job. The fish was only partially spawned out.

“It’s related to low water,” Vanbuskirk said. “The fish is just being attacked by so much stuff as far as disease, so any additional stress lets all that just kind of take over.”

After Western Washington saw the driest June to October on record, several storms were slated to soak the region beginning Oct. 21. It’s a welcome sight for many, including fish stuck downstream. But it comes at the risk of scouring eggs already laid in vulnerable places throughout the Northwest.

Extreme low river flows are just another blow to a species that’s already in crisis.

On a good day, this freshwater highway threading through Lewis County might be flowing at 300 cubic feet per second, Vanbuskirk said. On Oct. 20, it was about one-tenth of that.

As the first rain of the season began to fall the morning of Oct. 21, over two dozen river gauges documented levels below the 10th percentile of the flows ever recorded on the day. A streamflow between the 25th and 75th percentiles is considered normal.

Nearly all Western Washington rivers were near or at record low flows for weeks, following the dry spell. It prompted state, tribal and federal officials to close some fisheries, and it might have changed how fish spawn.

‘Feast or famine’

The morning of Oct. 20 just outside Stan Hedwall Park in Chehalis, a half-dozen purplish-maroon male chinook chased each other around the spawning grounds where females hovered. Their dorsal fins poked out into the hazy smoke-filled air as they raced through the shallows.

After successfully fending off the others, one dominant male swam beside a female — marked by her whitish tail. She turned on her side and began using her body and tail to move around the rocks, making way for her eggs.

State department of Fish and Wildlife biologists and technicians travel the river on one-person pontoons, stopping to count, tag and take notes on these egg nests, known as redds.

A whiteboard inside a tan tarp tent at Fish and Wildlife’s post in Rochester keeps a tally of these redds.

The week is typically considered part of the peak chinook spawning time in the Newaukum River. But that week’s column on the board is mostly a big line of zeros, punctuated by a couple of 2s. That means crews only have seen a few fish find their way into the south or north forks of the river to spawn. Instead their redds have been concentrated in the lower main stem.

Overall, chinook redd counts are down. That week, 45 were tallied in the Newaukum. That’s compared with last year’s 56, and redd counts topping 100 in 2019 and 2020.

The past four years, rains have helped dozens of these fish push their way into the upper tributaries to spawn, according to the state’s counts. Their redds were distributed across the river.

That distribution is important for survival.

“If you have spawning ground available throughout your watershed, you have more eggs in more baskets,” said Craig Smith, harvest program manager for the Nisqually tribe.

When there’s low water, chinook are relegated to spawn in the thalweg, or the lowest part of the river, said Pete Verhey, state fisheries biologist for the Snohomish and Stillaguamish basins. They’re deprived of fine gravels, and their redds are at risk of being destroyed by high water.

Maybe some of the fish are just “crossing their fins” and waiting until the rain helps move them upstream, Verhey said. Other biologists worry the rain came too late.

Across the state, coastal and inland biologists have reported fish “holding,” or waiting for rain to make their dash to higher spawning grounds.

Earlier this month, thousands of chinook were seen waiting to get upstream in the Quillayute River. Others have spawned in concentrated areas downstream.

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The first wave of rain also has the potential to “scour,” or wash out some of those unstable redds.

“It’s feast or famine,” Vanbuskirk said.

Biologists won’t know until spring out-migration counts how these eggs fared through the drought and downpour. Right now, all they see is it’s shifting how and where some salmon are spawning.

Trends threaten fish

Washington coastal rivers continue to experience negative fluctuations in flow. Peak flows have increased, and low flows have gotten lower since 1976, according to a 2020 report by the Northwest Indian Fisheries Commission.

Both trends could threaten fish.

Those low flows might be a product of increased demands on groundwater resources coupled with increasingly dry summers in Western Washington.

Bernard AfterBuffalo Jr. has watched coastal tributaries gradually warm and disappear since he started working for the Hoh Tribe in 2007.

“We’ve had numerous years with bad water quality for fish,” he said. “We’ve seen a couple of streams dry out that haven’t done so historically.”

It was gradual, AfterBuffalo said, until a “blob” of warm water parked itself off the West Coast. The blob — driven by a long-lasting high pressure ridge — appeared in 2013. It’s part of a larger pattern that led to low snowpack, drought and depleted marine nutrient levels.

Since then, every summer has been drier and drier.

AfterBuffalo and other fisheries workers recently began a desperate effort to save stranded fish — using buckets to move them out of pools and back into connected stream habitat. It’s what he calls “Operation Free Willy.”

Like AfterBuffalo, many fisheries leaders have “started getting used to this,” Smith said.

For about a decade, the Stillaguamish basin has seen these low flows putting pressure on spawning salmon, said Jason Griffith, environmental manager for the Stillaguamish Tribe.

In response, the Stillaguamish and other regional tribes have been working to restore critical rearing habitat to try to give the young fish a better shot at survival.

But there’s plenty affecting fish that’s out of their control.

Smith, the Nisqually fisheries leader, grew up in Washington. He said he doesn’t remember back-to-back years of wildfire smoke, extreme heat events and drought.

“The tribes have been fighting to protect their treaty rights for forever,” he said. “And this is just another blow when the environment is changing because of things beyond their control. Their environment is their treaty right. Clean water and fish are part of their treaty rights. And this is just sad and frustrating.”

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