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Fishes of Idaho

How are your identification skills? Do you know which are native and which were introduced? To see photos and descriptions, and learn more about Idaho fish, check out our Fishes of Idaho online database.

There are around 20,000 species of fish in the world. About 58% of these are marine (saltwater) fish, 41% are freshwater fish, and 1% are both. We have around 100 species in Idaho, and the list keeps growing as more non-native fish are released into Idaho waters. There are only 39 species of fish native to Idaho. The rest were introduced--some by accident, but most on purpose.

Minnows (Cyprinids)

Longnose dace (Rhinichthys cataractae)


The longnose dace is widely distributed across northcentral North America from the Atlantic to the Pacific. In Idaho, it is common in every river system in the state. They prefer the riffle areas of streams, but can be found along the shoreline of lakes where the substrate is composed of small rubble. It is a benthic species, living among the stones on the bottoms of streams. Longnose dace spawn in late spring/early summer on gravel bottoms of shallow riffles. Eggs, about 400 to 3,300 per female, are adhesive and are scattered on the substrate. The food of this species is primarily aquatic insect larvae. They reach a size of 3 to 6 inches. The fry of this dace may serve as food for game fishes and it has been used as a bait fish in parts of its range.

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