California's draught has dried up its rivers to the point where millions of baby Chinook salmon have to be transported by truck to complete their migration to the Pacific Ocean, the Associated Press reported.

This is not the first time the state has trucked six-month old salmon, or smolts, to protect them from California's dams and giant pumps. But wildlife authorities are adding to the load since the current drought, the driest in 100 years, has made it too dangerous for the young salmon to make the 300-mile swim to the San Francisco Bay.

"The drought conditions have caused lower flows in the rivers, warmer water temperatures, and the fish that would normally be swimming down the rivers would be very susceptible to predation and thermal stress," fishery biologist Kari Burr, from the Fishery Foundation of California, told the AP.

One salmon hatchery, the Coleman National Fish Hatchery, normally releases about 12 million smolts into Battle Creek, which flows into the Sacramento River. But so far this year the company has transported 7.5 million of the smolts by truck to the San Francisco Bay.

Federal and state wildlife agencies in general are trucking 27 million smolts, 50 percent more than usual, the AP reported.

Once released, the tide sweeps the smolts away into the ocean, allowing them to grow up and contribute to the state's seafood industry.

But fish experts say not letting the smolts migrate by river prevents them from being able to find their way home to reproduce in there years.

"Because the imprinting cycle is broken, it's unlikely that many fish will make it back to Coleman. In other words, they stray," Scott Hamelberg, manager of the Coleman National Fish Hatchery, told the AP. "They won't find that scent to where home is."