Snakes in Idaho

Idaho has only about 10+ species of snakes, and just 2 of them are venomous. Both are rattlesnakes. There are no copperheads or cottonmouths in Idaho or anywhere in the far West, so a venomous snake in Idaho always means a rattlesnake. That leaves 14 harmless species, and across much of the state you may go a long time without seeing any snake at all.

Idaho has a relatively short snake list because so much of it is high and cold. The Rocky Mountains, the high forests, and the elevated panhandle limit how many species can make a living here, since snakes need warmth and cannot survive long winters above certain elevations. The snakes concentrate in the warmer, lower country: the sagebrush steppe and high desert of the Snake River Plain in the south, the dry canyons of the Snake and Salmon rivers, and rocky south-facing slopes. The cool, wet northern forests hold very few species.

Idaho records 2 venomous kinds, both rattlesnakes. The Western Rattlesnake (in its Great Basin and northern Pacific forms) is the common one, found through the sagebrush flats, river canyons, and rocky slopes of the southern and central parts of the state. The Prairie Rattlesnake reaches in along the eastern edge near the plains. Both stay tied to warm, low, dry ground, so the high mountains and the moist panhandle are essentially rattlesnake-free.

Most snakes Idahoans meet are harmless. Gophersnakes are common and well known for their rattlesnake act, flattening the head, hissing, and buzzing the tail to bluff, despite having no venom or rattle. Garter snakes are the snakes most people actually see, hunting near streams, ponds, and gardens, and several kinds live across the state. Racers move fast over open ground, and the gentle rubber boa, a slow blunt-tailed burrower, turns up in cooler forests and meadows. Honest safety: nearly every serious snakebite in Idaho is a rattlesnake bite, and most happen when someone handles or corners a snake or reaches into rock and brush without looking. Deaths are very rare with antivenom and care. Give rattlesnakes room, watch your hands and feet on sunny rocky slopes, and never handle a wild snake. If a bite happens, call Poison Control at 1-800-222-1222 or 911.