California salmon lose way after ride downstream in drought

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A desperate decision to truck California’s native baby salmon toward the Pacific Ocean during the state’s drought may have resulted in generations of lost young salmon now hard-pressed to find their way back to their reproductive grounds.

With fewer native fall-run Chinook salmon able to make their way back home to the leading salmon hatchery in the state, that hatchery could have only about half as many young salmon as usual to release next spring, the Sacramento Bee reported Tuesday.

A salmon swimming in a holding tank on a boat in the Sacramento River in Rio Vista. /Reuters Photo

For those involved in safeguarding California’s struggling native salmon, it had always been understood that resorting to tanker trucks to carry tiny salmon to the ocean during the drought was a trade-off, John McManus, executive director of the fishing industry’s Golden State Salmon Association, told the Bee. Getting a lift on their migration saved countless salmon, but disoriented them.

“Everybody kind of acknowledged and understood at the time the consequences,” McManus said.

Native salmon historically anchored food chains and habitats on both land and in the water in California. Salmon still boost the state’s economy by 1.4 billion US dollars annually, the salmon industry says.

Dams that cut native salmon off from their former upstream spawning grounds, and general human demands on water, have helped cut salmon numbers drastically in the state, making state and federal hatcheries crucial for the fish.

Thousands of juvenile salmon are sent into a holding tank in the Sacramento River in Rio Vista. /Reuters Photo

California’s drought, declared over just last spring, included some of the driest spells ever recorded in the state. In 2014 and 2015, hatchery managers resorted to sucking baby salmon into tanker trucks for their 280-mile migration toward the ocean, biologists say. Chinook salmon spend two or three years in the ocean before heading back upstream to reproduce.

Since the 2014 class of salmon didn’t learn the route by swimming it on their own power, many have gone astray as they head back upstream now.

Biologists say only a small fraction of those made it back to what would be their usual point of return, at the Coleman hatchery. Salmon managers are tracking now how many of the strayed salmon wound up in other watersheds.

Source(s): AP