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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.

Pikes (Esocids)

Northern pike (Esox lucius)


Northern pike are aggressive, highly piscivorous (fish eating) predators native to north central and northeastern North America. Northern pike were illegally introduced into Idaho in the early 1970's. Originally planted in the "chain lakes" of the Coeur d'Alene River drainage, they rapidly spread throughout the system. The newly created fishery was instantly popular with many anglers, primarily because of the size of the fish. Northern pike growth during the initial population expansion was among the fastest ever recorded, with fish over 20 pounds being common. The current state record, caught in 1992, is 38 pounds, 9 ounces. Northern pike have since been illegally transplanted to several other lakes in the Idaho panhandle. Although popular with some anglers, northern pike have tremendous potential to devastate native fish populations, particularly cutthroat trout.

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