Mountain whitefish
Big Lost River
Updated
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Fish › Whitefish & grayling
Prosopium williamsoni
A native coldwater scrapper that shines on nymphs when trout fishing slows down.
Size range
9–28 in
Size range
Typical adult length in the waters we cover.
Water temperature
Coldwater
Water temperature
Preferred thermal regime for this species.
Active season
Year round
Active season
When anglers most often encounter this species.
Origin
Native
Origin
Stocking and native history where this species is found.
Habitat
Rivers & Large Rivers, Lakes & Reservoirs
Habitat
Primary water types where this species is found.
Mountain whitefish are native to Idaho and share many of the same rivers and lakes as trout. Often overlooked, they feed near the bottom and can provide steady action in clear, cold water.
Also known as: Whitefish
Mountain whitefish
Big Lost River
Mountain whitefish
Big Wood River
Mountain whitefish
Henrys Fork of the Snake River
Mountain whitefish
Henrys Fork of the Snake River, Box Canyon to Riverside
Mountain whitefish
Henrys Fork of the Snake River, Headwaters to Box Canyon
Mountain whitefish
Henrys Fork of the Snake River, Riverside to Mouth / terminus
Mountain whitefish likely in connected system
Kelly Creek
Likely in connected system
Mountain whitefish
Lochsa River
Mountain whitefish
Middle Fork Salmon River
Mountain whitefish
North Fork Coeur d'Alene River
Mountain whitefish
Saint Joe River
Mountain whitefish
Salmon River
Mountain whitefish
Salmon River, Bayhorse Recreation Site to Tappan
Mountain whitefish
Salmon River, Cache Bar to Carey Creek
Mountain whitefish
Salmon River, Campbell Flat to Pine Bar
Mountain whitefish
Salmon River, Carey Creek to Riggins
Mountain whitefish
Salmon River, Colston Creek to Shoup Bridge Campground
Mountain whitefish
Salmon River, Corn Creek Campground to Spring Bar
Mountain whitefish
Salmon River, Deadwater Spring to Corn Creek Campground
Mountain whitefish
Salmon River, Hammer Creek to Mouth / terminus
Mountain whitefish
Salmon River, Headwaters to Sawtooth Kids Pond
Mountain whitefish
Salmon River, Lucile Recreation Site to Campbell Flat
Mountain whitefish
Salmon River, Maynard Hole to Hammer Creek
Mountain whitefish
Salmon River, Riggins to Maynard Hole
Mountain whitefish
Salmon River, Sawtooth Kids Pond to Sunbeam
Mountain whitefish
Salmon River, Shoup Bridge Campground to Tower Rock Recreation Site
Mountain whitefish
Salmon River, South Butte to Bayhorse Recreation Site
Mountain whitefish
Salmon River, Spring Bar to Lucile Recreation Site
Mountain whitefish
Salmon River, Sunbeam to South Butte
Mountain whitefish
Salmon River, Tappan to Colston Creek
Mountain whitefish
Salmon River, Tower Rock Recreation Site to Cache Bar
Mountain whitefish
Selway River
Mountain whitefish
South Fork Boise River
Mountain whitefish
South Fork Snake River
Mountain whitefish
Teton River
They mainly eat bottom-dwelling aquatic insects, plus mollusks, fish eggs, and other small prey.
Always check the current Idaho Fish and Game rules for the specific river or reach before fishing, as regulations can vary by water.
Regulations vary by water. Check current Idaho Fish and Game rules before fishing.
Status: Native to Idaho (S3)
G5 (Secure) · ESA: Not listed · Idaho: S3Browse species profiles with habitat, diet, tactics, and linked waters across the state.
Mountain whitefish
Bear River, Cove Plant to Grace Dam
