State and federal wildlife officials announced a plan to move hatchery-raised salmon by truck in the event the state’s ongoing drought makes the Sacramento River and its tributaries inhospitable for the fish, reports the Sacramento Bee.
They fear the rivers could become too shallow and warm to sustain salmon trying to migrate to sea on their own.
Shrunken habitat could deplete food supply for the young fish, and make them easier prey for predators. It also would make the water warmer, which can be lethal to salmon.
“The conditions may be so poor as to produce unacceptable levels of mortality for the out-migrating juveniles,” said Bob Clarke, fisheries programme supervisor at the US Fish and Wildlife Service.
Clarke’s agency operates Coleman National Fish Hatchery on Battle Creek, a tributary of the Sacramento River near Red Bluff. It is the largest salmon hatchery in the state, producing about 12 million fall-run Chinook salmon. The hatchery was built to atone for habitat losses caused by construction of Shasta Dam.
Coleman hatchery salmon are usually released into Battle Creek in April and May. Fishery experts prefer to release young fish into rivers so they imprint on the location as “home” and are better able to migrate back from the ocean for spawning three to four years later.
