Chinook salmon have resumed their long truck trip from a federal hatchery near Red Bluff to San Pablo Bay, near Vallejo, an emergency measure to protect the fish during drought.
The U.S. Fish and Wildlife Service, which operates Coleman National Hatchery near Red Bluff, began the trucking operation March 24 to protect millions of juvenile fall-run Chinook salmon from low water levels and warm temperatures in the Sacramento River. It normally prefers to release the fish at the hatchery on Battle Creek, a tributary of the Sacramento River, so they can imprint on the location and more easily find their way back to spawn as adults in three years.
The agency trucked about 2.5 million salmon and released them into the Sacramento River at Rio Vista. Then on April 4, storm runoff improved river conditions, allowing the service over the succeeding days to release about 4.5 million salmon at the hatchery, according to usual practice.
Now, the runoff has abated and the trucking operation has resumed. . Fish and Wildlife expects to haul about 780,000 salmon in climate-controlled tanker trucks every day through Saturday. These fish will be released into San Pablo Bay, at Mare Island near Vallejo. They’ll spend a couple hours in floating net pens to acclimate to the higher salinity of the bay and to protect them from predators, then be released to migrate toward the ocean on their own.
Coleman hatchery is the largest salmon hatchery in California, producing about 12 million fall-run Chinook every year. These fish, as adults, form a major share of the state’s commercial and recreational salmon fishery, an industry worth about $1.5 billion annually.
The hatchery was built in 1942 to atone for the loss of natural salmon habitat caused by construction of Shasta Dam.
Call The Bee’s Matt Weiser at (916) 321-1264. Follow him on Twitter @matt_weiser.