Saving Seafood

As drought puts growing strains on fish, hatcheries serve as lifelines for California salmon

April 11, 2022 — When Shasta Dam was built on the Sacramento River in the 1940s, the government also established Coleman National Fish Hatchery about 30 miles away on the tributary Battle Creek, aiming to make up for the loss of upstream habitat by raising fish for release.

The hatchery’s staff runs an elaborate spawning operation that this year is raising 12 million fall-run Chinook salmon, supporting California’s commercial and recreational fisheries. The hatchery also raises other types of salmon and steelhead.

The adult salmon swim up the Sacramento River and into Battle Creek, then up a fish ladder to the hatchery’s holding ponds. Mechanical screens in the water are used to move the fish to the spawning building.

The fish are placed into a bath with carbon-dioxide in the water, which enables the staff to handle them. Workers lift the salmon from the water in nets, check to see that they’re ready for spawning, and separate females from males.

They club the fish and send them sliding down a metal chute. One worker hangs each female salmon from a hook, inserts a needle in its abdomen and sends air flowing to push out the eggs, which land in a colander. Another worker grabs each male fish and twists the tail, squeezing out milt that will fertilize the eggs.

Read the full story at the Los Angeles Times

California salmon are at risk of extinction. A plan to save them stirs hope and controversy

April 8, 2022 — Shasta Dam stands more than 600 feet tall, the height of a 55-story building, with a colossal spillway that towers over the Sacramento River in a curved face of concrete.

Since its completion in 1945, the dam has created California’s largest reservoir, which provides water for farms and cities across the state. But it has also blocked Chinook salmon from returning upstream to the cold, spring-fed streams near Mt. Shasta where they once spawned.

Cut off from that chilly egg-laying habitat, endangered winter-run Chinook have struggled to survive. They’ve had help from an elaborate spawning operation at a government-run fish hatchery, which is intended to function like a life-support system for the salmon.

But that support system is no longer enough. As global warming fuels worsening drought conditions and extreme heat, experts say winter-run Chinook are being pushed to the brink of extinction.

Last year, the water flowing from Shasta Dam got so warm that it was lethal for winter-run salmon eggs. Most of the eggs and young fish died. State biologists estimated that only 2.56% of the eggs hatched and survived to swim downriver, one of the lowest estimates of “egg-to-fry” survival yet.

Read the full story at the Los Angeles Times

These Chinook almost went extinct during California’s drought. Can this $100 million plan save them?

March 9, 2018 — During the worst of California’s five-year drought, thousands of eggs and newly spawned salmon baked to death along a short stretch of the Sacramento River below Shasta Dam.

The winter-run Chinook, already hanging by a thread, nearly went extinct.

Hoping to avoid a repeat of that dire scenario, fisheries officials announced Thursday the launch of a plan — nearly 20 years and $100 million in the making — they say would expand the spawning range of the fish to include a cold-water stream called Battle Creek. The idea is that the stream could keep the fragile winter-run alive as California’s rivers get hotter because of a warming climate.

The stakes are high and go well beyond the fate of the fish. Concerns about this run of salmon have a major impact on how water is distributed to farms and cities across California.

During the drought, for example, farmers experienced cuts to their water supply as dam managers held water in Shasta, the state’s largest reservoir, in a frantic effort to ward off extinction of the Chinook.

Read the full story at the Sacramento Bee