1 million Chinook salmon are returned to river fed by troubled Oroville Reservoir

More than a month after damage at the Oroville Reservoir triggered a massive evacuation of threatened fish, wildlife officials announced Monday that they had returned almost 1 million spring-run Chinook salmon to the Feather River.

The salmon were evacuated from the Feather River Hatchery in Oroville beginning Feb. 9, when officials realized a damaged spillway was sending countless tons of suffocating sediment into the river and hatchery holding areas.

The hatchery, which is owned and operated by the California Department of Fish and Wildlife, is the largest in the state. The roughly 10 million young salmon it releases each year in the Feather River and San Pablo Bay, near San Francisco, make up more than half of the annual ocean and inland catch in California.

“Today’s fish release marks the success of federal and state agencies coordinating and managing valuable resources while ensuring public safety during a crisis situation,” said Howard Brown, the Sacramento River basin branch chief for the National Oceanic and Atmospheric Administration, in a statement.

Central Valley spring-run Chinook are a state and federally listed species and their populations have suffered greatly during the drought.

Monday’s release gives the fish enough time to “imprint,” or memorize, the river so that they can return to it for spawning, according to officials. It also gives them enough time to swim downstream before the Department of Water Resources drops the river water level again later this week.

Another 1 million spring-run Chinook salmon and 3 million fall-run Chinook salmon are being kept at an annex hatchery, wildlife officials said.

During last month’s evacuation effort, an estimated 6 million of the salmon were trucked to another state wildlife facility about 10 miles from the turbid river.

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Staff writer Louis Sahagun contributed to this report.

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