The Animals Of Idaho

Section 01

Why Idaho Holds The Wildest Country In The Lower 48

Idaho contains the largest contiguous roadless area in the continental United States. The Frank Church River of No Return Wilderness and the adjoining Selway-Bitterroot together exceed 3.5 million acres with no roads through them, and that single fact explains most of what makes Idaho's wildlife different from its neighbours.

Animals that need space and tolerate no disturbance persist here in numbers unavailable elsewhere south of Canada: wolverine, mountain lion, gray wolf, and a growing grizzly presence. Roughly 63 percent of Idaho is federal land, the highest share of any state outside Alaska, Nevada, and Utah.

The geography is split in two. Northern Idaho, the panhandle, is wet, with inland temperate rainforest of cedar and hemlock receiving Pacific moisture, holding species otherwise found on the coast. Southern Idaho is the Snake River Plain, a vast arc of lava and sagebrush steppe that is dry, cold in winter, and ecologically closer to Nevada. Between them run the central mountains.

The Snake River ties it together and creates Idaho's defining conservation conflict. Salmon and steelhead born in Idaho streams travel roughly 900 miles to the Pacific and back, climbing over 6,500 feet in elevation, the longest and highest salmon migration remaining anywhere. Eight dams on the Snake and Columbia now stand in the way, and Idaho's Snake River sockeye came within a single returning fish of extinction.

Section 02

Idaho's Official State Animals

The Appaloosa is a Nez Perce breed. The tribe developed it in the Palouse country over generations, and most of the horses were seized or dispersed after the 1877 war, with the breed rebuilt in the 20th century. The Hagerman horse fossil, from beds along the Snake River, is one of the earliest known members of the modern horse genus.

Section 03

Habitats By Region, And Who Lives In Each

1. Panhandle inland rainforest

Western red cedar and western hemlock forest fed by Pacific moisture, unusually lush for a landlocked region. Species include mountain caribou, which used the Selkirks and are now effectively gone from the US, plus grizzly bear in the Selkirk and Cabinet-Yaak recovery zones, Canada lynx, fisher, moose, and coastal disjunct amphibians like the Coeur d'Alene salamander.

2. Central mountains and wilderness core

The Salmon River, Sawtooth, Bitterroot, and Clearwater country: granite peaks, deep canyons, and the roadless heart of the state. Elk, mule deer, mountain goat, bighorn sheep, gray wolf, mountain lion, wolverine, and black bear. Streams here hold bull trout and the spawning gravels for Idaho's remaining salmon and steelhead.

3. Snake River Plain and sagebrush steppe

Lava fields, sagebrush, and irrigated farmland across southern Idaho. Sagebrush is the key habitat and the most threatened: greater sage-grouse, pygmy rabbit (the smallest rabbit in North America and a sagebrush obligate), sage thrasher, Brewer's sparrow, pronghorn, and ground squirrels including two endangered Idaho endemics.

4. Snake River canyon and Hells Canyon

Hells Canyon is the deepest river gorge in North America, deeper than the Grand Canyon. Warm, dry, and steep, it holds bighorn sheep, chukar, rattlesnakes, and the densest raptor nesting in the region along the Snake River. White sturgeon in the river below can exceed ten feet and live over a century.

5. Eastern Idaho and the Yellowstone edge

The Caribou-Targhee country adjoining Yellowstone and Grand Teton, with lodgepole and spruce-fir forest. This is Idaho's link to the Greater Yellowstone Ecosystem: grizzly bears, wolves, elk, moose, trumpeter swans wintering on spring creeks, and the Yellowstone cutthroat trout.

Section 04

Mammals Of Idaho

• Elk: roughly 120,000, and Idaho is one of the premier elk states. Herds in the Clearwater declined sharply after wolf recovery and habitat succession, and the interaction between the two remains contested. See where to watch the elk rut.
• Mule deer and white-tailed deer: mule deer statewide, whitetails mainly in the panhandle and river bottoms.
• Moose: several thousand, mainly in the north and east, and unusually visible in Idaho's willow bottoms.
• Pronghorn and bighorn sheep: pronghorn on the southern plains, with both Rocky Mountain and California bighorn subspecies in separate ranges. Disease from domestic sheep remains the limiting factor.
• Mountain goat: native here, unlike in Colorado, on the high central peaks.
• Bison: no wild free-ranging herd in Idaho, though animals occasionally cross from Yellowstone. Related: state parks where bison still roam.
• Gray wolf: reintroduced to central Idaho in 1995 alongside Yellowstone, with 15 wolves released initially. The population grew to well over a thousand and was federally delisted in 2011. Idaho has since adopted aggressive reduction policies, and wolf management here is among the most contested wildlife issues in the country.
• Grizzly bear: present in small numbers in the Selkirk, Cabinet-Yaak, and Yellowstone-adjacent areas, with the Bitterroot recovery zone largely unoccupied. See where grizzly bears live.
• Black bear, mountain lion, bobcat, lynx, wolverine, fisher, marten, badger, river otter, beaver, coyote, red fox, kit fox: a nearly complete native carnivore guild, which very few states can still claim.
• Pygmy rabbit: North America's smallest rabbit, about a pound, digging its own burrows in deep sagebrush soils. The Columbia Basin population in Washington is endangered; Idaho holds core range.
• Northern Idaho and southern Idaho ground squirrels: both endemic to small areas of the state and both federally listed.
• Mountain caribou: the last herd using the US portion of the Selkirks dwindled to a handful and no longer persists south of the border, making caribou functionally extirpated from the lower 48. Background: caribou facts.

Section 05

Birds Of Idaho

Around 430 species have been recorded. Idaho's specialty is raptors and sagebrush birds.

• Raptors: the Morley Nelson Snake River Birds of Prey NCA supports exceptional nesting densities of prairie falcon, golden eagle, red-tailed hawk, and several owls, drawn by enormous ground squirrel and jackrabbit populations on the plain below the cliffs. Also bald eagle, ferruginous hawk, Swainson's hawk, northern goshawk, and the peregrine falcon, the state raptor.
• Sagebrush birds: greater sage-grouse, sage thrasher, Brewer's sparrow, sagebrush sparrow, and loggerhead shrike. All decline with sagebrush conversion, cheatgrass invasion, and the larger and more frequent fires that cheatgrass fuels.
• Forest birds: Clark's nutcracker, mountain bluebird (the state bird), varied thrush and Pacific wren in the panhandle rainforest, three-toed and black-backed woodpeckers in burned forest, boreal owl, and great gray owl.
• Waterbirds: trumpeter swans wintering on spring-fed creeks in the east, white pelicans and Franklin's gulls at Bear Lake and Blackfoot Reservoir, long-billed curlew on wet meadows, and sandhill cranes breeding in the valleys.

Section 06

Salmon, Steelhead, And The Idaho Fish Story

This is the single most consequential wildlife issue in the state, and it is worth understanding in full.

Chinook salmon, sockeye salmon, and steelhead hatch in Idaho streams, migrate to the Pacific as juveniles, spend one to several years at sea, and return to spawn in the same gravel where they hatched. The Idaho leg is extraordinary: roughly 900 river miles inland and over 6,500 feet of elevation gain, the longest and highest salmon run left on Earth. Redfish Lake in the Sawtooths, named for the crimson sockeye that once filled it, sits at 6,500 feet.

Eight federal dams on the lower Snake and Columbia now sit between Idaho and the sea. Juveniles must pass all eight going down and adults all eight coming up. Historic runs numbered in the millions. In 1992 exactly one Snake River sockeye returned to the Sawtooth basin, a male nicknamed Lonesome Larry, and the entire lineage was rebuilt from captive broodstock derived from a handful of fish.

• Snake River sockeye: federally endangered, sustained largely by hatchery intervention.
• Snake River spring, summer, and fall Chinook: threatened, with returns far below recovery targets.
• Steelhead: threatened, and culturally and economically central to central Idaho towns.
• Bull trout: threatened, requiring very cold, clean, connected water, which makes it an indicator of stream health.
• White sturgeon: landlocked between dams in the Snake, long-lived and no longer able to complete natural migrations.
• Cutthroat trout: the state fish, in Westslope and Yellowstone forms, threatened mainly by hybridisation with introduced rainbow trout.

Whether to breach the four lower Snake River dams is the central policy question. Related: the rivers where salmon returned after the dams came down.

Section 07

Dangerous Animals In Idaho

• Moose: the most likely animal to injure a person in Idaho. Cows with calves and rutting bulls both charge, and dogs provoke them.
• Grizzly bear: present in the east and north. Carry bear spray, make noise on blind trails, and store food properly. Attacks are rare but this is the one animal that warrants real preparation.
• Black bear: common statewide and mostly a food-conditioning problem.
• Mountain lion: widespread and rarely seen. Attacks are very rare.
• Western rattlesnake: the state's only venomous snake, in the Snake River canyon, Hells Canyon, and dry southern country. Bites are uncommon.
• Wolves: no verified fatal wolf attack on a person has occurred in Idaho. Livestock and hunting dogs are the practical conflict.
• Cold water and swift rivers: Idaho's rivers injure and kill far more people than its wildlife.

Section 08

Endangered And Protected Species

The pressures are dams and water diversion for anadromous fish, cheatgrass and altered fire regimes destroying sagebrush, disease transmission from domestic to wild sheep, road and residential development fragmenting migration corridors, and spring-fed Snake River habitats altered by aquaculture and groundwater pumping. Idaho's advantage is that its habitat is largely intact at a scale most states cannot match.

Section 09

Where To See Wildlife In Idaho

• Morley Nelson Snake River Birds of Prey NCA: raptor nesting density unmatched in the region, best in April and May.
• Sawtooth National Recreation Area and Redfish Lake: sockeye return in August and September, plus elk, moose, and mountain goat.
• Frank Church River of No Return Wilderness: wolves, bighorn, and elk in genuinely roadless country, accessible by raft or backcountry airstrip.
• Hells Canyon: bighorn sheep, chukar, and sturgeon, best by jet boat or raft.
• Camas National Wildlife Refuge and Market Lake: waterfowl, cranes, and swans.
• Harriman State Park and Henrys Fork: trumpeter swans, moose, and one of the most famous trout rivers in the world.
• Coeur d'Alene and the panhandle forests: inland rainforest species and moose.
• Craters of the Moon National Monument: sagebrush and lava-adapted wildlife.