Fish Species of the American River (California): A Diverse Fishery

The American River, a major tributary of the Sacramento River in California's Sierra Nevada foothills, supports a remarkably diverse fish community. Its waters host native anadromous species, resident natives, and introduced game fish.

Anadromous Species (Ocean-Migrating)

These fish hatch in freshwater, mature in the Pacific Ocean, and return to the American River to spawn.

• Chinook Salmon (Oncorhynchus tshawytscha) – Fall and spring runs; keystone species.
• Steelhead Trout (Oncorhynchus mykiss) – Sea-run rainbow trout; threatened (Central Valley DPS).
• American Shad (Alosa sapidissima) – Introduced from East Coast; popular sport fish.
• Striped Bass (Morone saxatilis) – Introduced; predatory, follows shad runs.
• Other Pacific Salmon (less common): Coho, Pink, Sockeye, Chum – occasional strays.

Native Resident Freshwater Species

These fish complete their entire life cycle in the river.

• Rainbow Trout (Oncorhynchus mykiss) – Native resident form (non-anadromous).
• Sacramento Sucker (Catostomus occidentalis) – Bottom-feeder, abundant.
• Sacramento Pikeminnow (Ptychocheilus grandis) – Large native minnow, apex predator in lower river.
• Hardhead (Mylopharodon conocephalus) – Native cyprinid, prefers deep pools.
• California Roach (Hesperoleucus symmetricus) – Small, tolerant minnow.
• Riffle Sculpin (Cottus gulosus) & Piute Sculpin (Cottus beldingii) – Bottom-dwellers in riffles.
• Hitch (Lavinia exilicauda) – Native minnow, slow-water habitats.

Introduced Game Fish (Established Populations)

• Brown Trout (Salmo trutta) – European native; popular in upper river.
• Largemouth Bass (Micropterus salmoides) – Warm-water predator in reservoirs/lower river.
• Smallmouth Bass (Micropterus dolomieu) – Cooler water; strong fighter.
• Spotted Bass (Micropterus punctulatus) – Native to eastern US; established here.

Conservation Notes

• Chinook salmon and steelhead are listed under the Endangered Species Act (ESA).
• Folsom and Nimbus Dams block historic spawning habitat; hatcheries mitigate losses.
• Water temperature management, flow releases, and habitat restoration are ongoing priorities.
• Angling regulations (seasons, gear, limits) protect vulnerable runs—check CDFW current rules.

The American River's fish assemblage reflects both its ecological heritage and a century of human modification.