As 6-month old salmon smolt head to the ocean, their home river is imprinted on them. They spend 2 years in the ocean and then return home to spawn. But, due to severe drought conditions in California, many of the smolt are hitching a ride on hatchery trucks to get them to the ocean; breaking the imprinting process.
Fortunately for Battle Creek, rains in April improved the river level enough for the hatchery in Shasta County to release 4.5 million smolt. But other rivers are not so lucky.
Read more from YahooNews: Salmon migrate by truck during California drought