Species Raised at Trinity River Hatchery

Chinook Salmon

Chinook salmon have seventeen distinctive runs in California. These runs vary in many ways, and are categorized into 6 Evolutionarily Significant Units. Some units have been listed as threatened species. Trinity River Hatchery spawn, raises and release to the Trinity River spring-run and fall-run Chinook salmon of Trinity River origin.

Steelhead Trout

Steelhead trout are an anadromous form of the rainbow trout that go to the ocean for one or more years and then return to spawn upstream, similar to a salmon. They differ from salmon in that a steelhead may spawn and return to the ocean, and then spawn again in another year.

Coho Salmon

Coho salmon, endangered in the state of California, are medium to large salmon with sizes up to 22 lbs. While providing for a popular fishery in other areas of the Pacific Northwest, recreational angling for coho salmon in California is prohibited. The most reliable identification of these fish comes from the black jaw with white/grey gums.

Seasonal Activities

The hatchery traps returning adult salmon and steelhead and holds them until the fish are ready to be spawned. Salmon and steelhead eggs are fertilized, and then incubated for approximately 50-60 days depending on water temperatures. When the young fish are ready to eat they are taken directly to hatchery troughs or to hatchery raceways. The juvenile fish are reared and then released into the Trinity River where they migrate to the ocean.

Chinook salmon - Spring run

Trinity River spring-run Chinook salmon enter the Lower Klamath River in late March and April and proceed up the Trinity River. They arrive in the upper river any time from the middle of May to the first part of July. Spring Chinook provide most of the salmon fishing opportunities for river anglers and are also important to the local economy. Although arriving early in the year, these fish do not spawn until about mid-September. The hatchery ladder is not opened until September after Labor Day, because the fish hold better in the large deep pool below Lewiston Dam than they do for extended periods in hatchery holding ponds.

Chinook salmon - Fall run

Trinity River fall-run Chinook salmon enter the Klamath estuary from mid to late August and will arrive at the hatchery in early October. This run is particularly important to the commercial ocean fishery as well as the Native American fishery.

Coho salmon

Trinity River coho salmon appear at the Trinity River Hatchery about mid-October and spawning extends through December. While providing for a popular fishery in other areas of the Pacific Northwest, recreational angling for coho salmon in California is prohibited.

Steelhead

Steelhead arrive at the hatchery from about the first of November through March. They are spawned and then returned to the river. Steelhead are an anadromous form of rainbow trout. These fish return from the ocean after a few years to spawn in rivers and creeks similar to a salmon. They differ from salmon in that a steelhead may spawn and return to the ocean more than once.

Spawning

The fish ladder is operated from the first week in September through the second week of March. Spawning operations occur every Monday and Thursday during salmon spawning season (first week in September through the second week of December) for salmon and on Tuesdays (last week in December through the second week in March) for Steelhead. Be sure to arrive early as spawning operations start around 7:30 a.m. and depending on the number of fish in the trap, spawning may end before noon.

Trinity River Hatchery main page

Fisheries Branch
1010 Riverside Parkway, West Sacramento, CA 95605 | Fisheries@wildlife.ca.gov