Idaho AFS Logo

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.


Bull trout (Salvelinus confluentus)


Bull trout are Idaho's only native species of char-a sub-group of the trout and salmon family that is distinguished by light-colored spots and fall spawning. Bull trout are secretive fish that require extensive cover in the form of pools, streamside vegetation and log jams. In addition, they require very cold water. Because of their particular habitat requirements, bull trout are extremely sensitive to habitat degradation. Non-native species, such as lake trout and brook trout BULL TROUTa.jpg (14874 bytes)also threaten bull trout through predation, competition, and hybridization. Overharvest and poaching have contributed to the decline of bull trout populations in Idaho as well. Because of the depressed and declining status of bull trout, they are listed as a threatened species under the Federal Endangered Species Act.

Click thumbnails to enlarge