20 Million Young Chinook Salmon Released Into the Wild!

Just in time for fishing season, hatcheries operated by the Central Valley California Department of Fish and Wildlife (CDFW) have completed the final release of Chinook salmon. These smolts are raised in state-run hatcheries and released yearly into the Sacramento and San Joaquin rivers, the Delta and San Pablo bay. In two years or so, they return as adults to Central Valley tributaries to spawn.

The hatchery-reared fish make up the bulk of commercial Chinook caught off the California coast, and are the vast majority of the sport fishing catches in the Pacific and Central Valley river system.

“This year was especially challenging with the restrictions involved due to COVID-19,” said Colin Purdy. “But rearing, tagging and releasing these young salmon was vital and essential to the future of our Chinook salmon stocks in the Central Valley. The whole process started last fall when eggs were taken at the hatcheries.”

According to the CDFW, an estimated 271,697 Chinook salmon were harvested off the California coast by commercial fishermen, while approximately 88,464 were caught by recreational anglers and inland river fishermen reeled in more than 28,000 during the 2019 fishing season. There are four Central Valley hatcheries operated by CDFW as well as the Coleman National Fish Hatchery operated by the U.S. Fish and Wildlife Service that produced the bulk of the 2019 harvest. California’s commercial and recreational salmon fishery is estimated to generate more than $500 million in annual income.

Hatcheries by the numbers:

  • Feather River Hatchery produced 6.4 million fall-run Chinook salmon and 1.75 million spring-run Chinook salmon. 
  • Nimbus Fish Hatchery produced 4.4 million fall-run Chinook salmon 
  • Merced River Hatchery produced 1.1 million fall-run Chinook salmon
  • Mokelumne River Hatchery produced 4.3 million fall-run Chinook salmon for their mitigation program, and an additional 3 million (also fall-run) for the Commercial Salmon Trollers Enhancement and Restoration Program.

Before release, a portion of the young salmon are tagged to allow scientists to track their eventual contribution to sport and commercial fisheries and their return rates.

All salmon are released into the wild between February and June via tanker trucks modified to carry the smolts. Most are released along their home rivers, while some are placed in net pens in San Pablo Bay or along the coast. During the five month release program, there are roughly 50 releases delivering hundreds of thousands of smolts throughout the central valley.

“The coordination and logistics of spawning, rearing, tagging, transporting and releasing millions of smolts is a challenging job under normal circumstances,” Purdy said. “More than 100 employees – from fish pathologists to hatchery managers, staff and truck drivers – have to be scheduled throughout the cycle, well in advance of final release of fish. In light of this year’s rapidly evolving conditions and challenges, the completion of our 2020 releases is an especially sweet success.”

The Chinook salmon is the largest of the Pacific salmon species, averaging 3’ long and weighing in at about 30 lbs. They’re blue-green with silver sides. The salmon’s tail, back, and upper third sport black spots. During mating season, both male and female Chinook develope a reddish tint on their fins and tail.

With an annual budget of more than $540 million, the California Department of Fish and Wildlife is a state agency  whose mission is to “manage California’s diverse fish, wildlife, and plant resources, and the habitats upon which they depend, for their ecological values and for their use and enjoyment by the public. You can find out more about the CDFW HERE.