Drought prevents salmon from returning to hatchery

A chinook salmon waits to be let into the holding pond from the Tulalip Bay fish ladder.

Chinook salmon wait to be let into the holding pond from the Tulalip Bay fish ladder.

Tribal fishing in Tulalip Bay closed in July because a thermal barrier kept many salmon from entering the bay, and low flows prevented others from swimming upriver.

Tulalip Tribes closed fishing in the bay July 22, and the state restricted the sport chinook fishery in the “bubble” at the mouth of the bay to catch-and-release as of July 31.

Normally, chinook salmon return via the Skykomish River to the state’s Wallace River Hatchery, where they are spawned for the Tulalip Tribes’ and state’s joint hatchery program. But this year, along with other rivers in the region, the Skykomish is setting records for the lowest flows ever recorded.

“Wallace River Hatchery doesn’t have enough fish,” said Mike Crewson, Tulalip salmon enhancement scientist. “Escapement is really low. The fish cannot make it up there in the shallow water. They’re all holding down in the lower pools of the Skykomish and Snohomish mainstems. They don’t want to come into Tulalip Bay even, because it’s too warm.”

Temperatures around 70 degrees can be lethal for salmon. In rivers, pathogens such as Ichthyophthirius multifiliis (ich) and columnaris (gill rot) thrive in warm water. The diseases spread more quickly when the rivers are crowded by low flows, and can lead to increased pre-spawn mortality.

“Returning adult fish will find pockets of cool water to hold in if river temperatures are not favorable,” said Bruce Stewart, NWIFC fish health program manager. “They will hold in these pockets as long as they can. However, if they have to hold for any length of time in temperatures as high as 70-75 degrees they will have to deal with fish pathogens that like that temperature range. Egg production in a compromised fish probably will be lower.”

To collect broodstock, the tribe opened up its fish ladder in Tulalip Bay the week of July 20. After a weekend of slightly lower temperatures and a small amount of rain, about 40 chinook made it through the bay to the fish ladder on July 27, and another 50 on July 28. But only about a third of those fish will result in viable female spawners that provide the eggs needed.

“We have less than a hundred fish and we need a few thousand for the joint program,” Crewson said.

The co-managers have an arrangement where the state gets the first 1 million eggs to release into the Wallace River, and Tulalip gets the next 800,000 to release from its hatchery. They split the remaining eggs.

While fry released from the Tulalip Tribes’ Bernie “Kai-Kai” Gobin Hatchery provide fishing opportunities for both tribal and sport fishermen in Tulalip Bay, the Wallace River releases are essential to keep the run going, Crewson said.

“Even though it doesn’t benefit us immediately, it benefits us in the long term,” he said.

The adult fish collected in the ladder are being held in the return ponds instead of being transported to the hatchery, in part to reduce the stress to the fish, but also because there’s no water available to hold them at the hatchery.

Most years, the hatchery has enough surface water to fill its ponds, but this year, water has to be recycled to accommodate two ponds of yearling coho.

“And we’re running the well all summer long,” Crewson said. “Between all of that and the surface water, it’s only enough for one pond.”

For more information, contact: Mike Crewson, Tulalip Tribes, 360-716-4626 or ; Kari Neumeyer, NWIFC, 360-424-8226 or .

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