200,000 Salmon Getting Released into San Francisco Bay
The California Department of Fish and Wildlife (CDFW) is nearing the completion of its efforts to transport 19.7 million hatchery-raised fall-run and 960,000 spring-run juvenile Chinook salmon (known as smolts) to the San Pablo Bay, San Francisco Bay and seaside net pens this spring and summer.
CDFW raises the fish at Feather River, Nimbus, Mokelumne and Merced salmon hatcheries and monitors river conditions carefully to estimate the smolts’ chances of successful migration. During times of drought, low flows and elevated water temperatures can be a lethal mixture for the young salmon.
Why release downstream this year? In 2022, conditions are expected to be particularly poor, prompting CDFW to move more than 95 percent of the smolts down river, thus bypassing 50 to 100 miles of hazardous river conditions.
According to Bay City News, this the first-ever release of this kind in Richmond.
The releases began in March and are scheduled to conclude by June 23. One of the last releases will happen over the weekend at Brickyard Cove in Richmond on Sunday, June 19 at 8:45 p.m.
The Golden State Salmon Association and the City of Richmond will assist with the release of approximately 200,000 smolts at this site.
Please note that its unclear if the public can witness the release.
How They Monitor Salmon Survival Rates
To increase survival rates, multiple release sites and release methods are used. In some locations, the fish are released directly into the water by specialized fish-hauling tanker trucks. At others, the smolts are released into net pens, which are then towed out to deeper waters before being released. Releases can happen during daylight hours or at night. CDFW fisheries biologists and salmon hatchery managers tailor these methods according to tide conditions, temperatures and the presences of potential predators at each site.
Prior to each release, approximately 25 percent of the smolts have their adipose fin removed and are fitted with a coded wire tag the size of a small pencil lead in its nose. When the fish are caught later, CDFW staff can use the tag information to determine when, where and from which hatchery the fish came. CDFW fish counters check both commercial and sport catch to secure tags and retrieve this information, which helps determine the success rate of each batch of fish released.