Skip Navigation

Species Search:
FieldGuidesthreatened and/or endangered search resultsthreatened and/or endangered

previous  | next

Cutthroat Trout Oncorhynchus clarki


enlarge +

Cutthroat Trout
credit: Kriscotta

All Images

1 article:

Get Our Newsletters


Advanced Search

Family: Salmonidae, Trouts view all from this family

Description The cutthroat trout (Oncorhynchus clarkii) is a species of freshwater fish in the salmon family of order Salmoniformes. It is one of the many fish species colloquially known as trout. All subspecies of cutthroat trout are sought after gamefish, especially among anglers who enjoy fly fishing.

Several native subspecies of cutthroat are currently listed as threatened, generally due to loss of habitat and introduction of non-native species.

Cutthroat trout are native to western North America. The cutthroat species has evolved through geographic isolation into many subspecies, each native to a different major drainage basin. Native cutthroat species are found along the Pacific Northwest coast, in the Cascade Range, the Great Basin, and throughout the Rocky Mountains. Some coastal populations are anadromous, living primarily in the Pacific Ocean as adults and returning to fresh water from fall through early spring to feed on insects and spawn. Most populations, however, stay in freshwater throughout their lives and are known as non-migratory, stream-resident or riverine populations. Anadromous fish may reach weights of 20 pounds (9 kg), but those fish which remain permanently in freshwater may only reach a weight of 2 pounds (1 kg). At least three subspecies are confined to isolated basins in the Great Basin and can tolerate saline or alkaline water.

Dimensions Up to 30" (76 cm); 41 lbs (18.6 kg).

Endangered Status Three subspecies of the Cutthroat Trout are on the U.S. Endangered Species List. The Lahontan Cutthroat Trout is classified as threatened in California, Nevada, Oregon, and Utah. The Paiute Cutthroat Trout is classified as threatened in California. The Greenback Cutthroat Trout is classified as threatened in Colorado. The decline of these subspecies can be attributed to changes in habitat, usually caused by water-management practices but also by livestock grazing and the mining and timber industries; overfishing; and the introduction of non-native fishes which prey upon, compete with, and hybridize with the natives. A newly introduced illness called whirling disease may also develop into a major threat.

Habitat Estuaries, tidal flats & salt marshes, Lakes & ponds, Ocean or bay shallows, Rivers & streams.

Range Rocky Mountains, Southwest, California, Northwest, Western Canada, Alaska.