Shrinking Sonoma County streams put young coho salmon in peril

About 30,000 juvenile coho salmon may be doomed by the drought as Sonoma County streams shrink and become disconnected from the Russian River, trapping the young fish in pools that will dry up or degrade over the long, hot summer, experts say.
The parched conditions have appeared earlier this year than any other in the state’s current dry spell, and they could prove the deadliest in recent record to the imperiled coho, the focus of 14-year-old restoration effort costing millions of dollars.
“It’s grim. It’s going to be a rough year for the coho,” said Mariska Obedzinski, a fish biologist who coordinates the UC Cooperative Extension’s coho monitoring program. “They can’t get where they need to go.”
At the same time, another 50,000 coho juveniles, known as smolts, are due for release from the Don Clausen Fish Hatchery below Warm Springs Dam on Lake Sonoma and scientists are considering which streams will give the endangered fish the best chance of achieving their biological goal of reaching the Pacific Ocean this spring.
Two coho spawning streams — Porter and Pena creeks — are already cut off from the river. If no more rain falls, other tributaries, including Green Valley, Dutch Bill and Mill creeks, will likely go dry in spots, Obedzinski said.
The California Department of Fish and Wildlife is already planning rescue operations to save the smolts and younger fish in disconnected streams.
Read more via Shrinking Sonoma County streams put young coho salmon | The Press Democrat.

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