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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)

Peamouth chub (Mylocheilus)


The peamouth chub is a western minnow native to the Columbia River system and coastal drainages of OR, WN, ID, MT, and British Columbia. It also is found in Alberta. In Idaho, this species is native to the Snake River and tributaries below Shoshone Falls, and the Coeur d'Alene, Pend Oreille, and Kootenai River systems. It prefers lakes and slow-moving portions of streams and will concentrate where aquatic vegetation is present. Peamouth spawn in shallow water of streams and along lake shores over a gravel or rubble bottom. In late spring, eggs are broadcast on the bottom where they adhere to the substrate. From 5,000 to over 30,000 eggs are produced per female, depending on age and size. This species attains a size of 9 to 12 inches in length. They feed on a variety of small, aquatic invertebrates. Peamouth can be taken on hook and line, but are not sought after by most fishermen. Their young serve as forage for predaceous fishes.

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