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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.

Sculpins (Cottids)

Slimy sculpin (Cottus cognatus Richardson)


The slimy sculpin is a wide-ranging species found in Siberia, and in North America from Alaska to WN, across Canada and in the eastern U.S. In Idaho, this species is found in the Kootenai and Pend Oreille drainages, and in the Little Salmon River. Generally this species is found in riffle areas among rocks of cold, clear streams, but it can be found along gravel beaches of lakes. This species spawns in the spring. Females lay eggs under rocks and are guarded by males, as in other sculpins. They feed on a variety of aquatic invertebrates. They may attain lengths of 4 inches or slightly more, but most adults are 2 to 3 inches in length. This species is small and is eaten by trouts, northern pike, and burbot.

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