The Snake River fine-spotted cutthroat trout is a form of the Yellowstone cutthroat trout

Yellowstone cutthroat trout

The Yellowstone cutthroat trout is a subspecies of the cutthroat trout and is a freshwater fish in the salmon family of the order Salmoniformes. Native only to a few U.S...

 (Oncorhynchus clarki bouvieri) subspecies. Sub-species designation has been proposed with a trinomial classification of Oncorhynchus clarki behnkei, but the sub-species is not formally recognized. This cutthroat trout

Cutthroat trout

The cutthroat trout 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...

 takes its common name from its original habitat, the Snake River

Snake River

The Snake is a major river of the greater Pacific Northwest in the United States. At long, it is the largest tributary of the Columbia River, the largest North American river that empties into the Pacific Ocean...

 of southern Idaho

Idaho

Idaho is a state in the Rocky Mountain area of the United States. The state's largest city and capital is Boise. Residents are called "Idahoans". Idaho was admitted to the Union on July 3, 1890, as the 43rd state....

 and western Wyoming

Wyoming

Wyoming is a state in the mountain region of the Western United States. The western two thirds of the state is covered mostly with the mountain ranges and rangelands in the foothills of the Eastern Rocky Mountains, while the eastern third of the state is high elevation prairie known as the High...

, and from its unusual pattern of hundreds of small spots that cover most of its body.

Hybrids

While fine-spotted x rainbow trout

Rainbow trout

The rainbow trout is a species of salmonid native to tributaries of the Pacific Ocean in Asia and North America. The steelhead is a sea run rainbow trout usually returning to freshwater to spawn after 2 to 3 years at sea. In other words, rainbow trout and steelhead trout are the same species....

 crosses are observed in the South Fork of the Snake River in Idaho, they are infrequently encountered and appear to be hatchery

Hatchery

A hatchery is a facility where eggs are hatched under artificial conditions, especially those of fish or poultry. It may be used for ex-situ conservation purposes, i.e. to breed rare or endangered species under controlled conditions; alternatively, it may be for economic reasons A hatchery is a...

 hybrids. Conversely, Yellowstone x rainbow crosses are common; the "cutbow

Cutbow

A Cutbow is a fertile hybrid between a rainbow trout and a cutthroat trout . While cutbow hybrids may occur naturally, most native populations of rainbows and cutthroats were separated by geography or habitat...

s" of Yellowstone Park in the Lamar River

Lamar River

The Lamar River is a tributary of the Yellowstone River, approximately 40 miles long, in northwestern Wyoming in the United States. The river is located entirely within Yellowstone National Park.-History:...

 drainage are natural hybrids.

Diet

In addition to their natural aversion to cross-breeding with other trout, fine-spotted cutthroats are unusual in their pursuit of a vertebrate diet, mainly other fish, but occasionally including small mammals. They are the only river cutthroat with a vertebrate diet, and as a result their territorial waters are almost devoid of whitefish

Coregonus

Coregonus is a diverse genus of fish in the salmon family . The type species is the common whitefish . The Coregonus species are known as whitefishes...

. While the fine-spotted cutthroats can be very selective feeders during a major hatch of aquatic invertebrates, they are not as focussed as rainbow or brown trout

Brown trout

The brown trout and the sea trout are fish of the same species....

, and can be diverted with small terrestrial imitations. In addition, when there is no obvious hatch, anglers can be very successful with large streamer flies that imitate small fish.