Endangered Species of the Western United States

We know what success can look like. We know from the Endangered Species Act and many other initiatives to restore habitat and wildlife that species can make a comeback. Here are just a few from the Western United States! 

Sea otters are a keystone species in their coastal ecosystems. By controlling the populations of green sea urchins, which graze on undersea kelp forests, sea otters help ensure healthy nursery habitats for fish and other species. 

Sea otters are common in many accessible coastal areas in Southeast Alaska, including Glacier Bay National Park, and in South central Alaska, such as Kenai Fjords National Park.

Bighorn sheep live in steep mountainous habitat, with ledges sometimes only two inches wide, provides cover from predators. Most populations undergo seasonal movements, generally using larger upland areas in the summer and concentrating in sheltered valleys during the winter. 

Bighorn sheep are found in TNC’s Aravaipa Canyon Preserve in southern Arizona.

Unlike most endemic species in Hawai‘i which lost their defenses due to lack of predators, the hāhā evolved with large thorns on the lower part of its new growth. One theory suggests that the thorns are a defense against herbivory by the moa-nalo, a group of tall flightless ducks that went extinct on the islands within the last 1600 years! 

Hawaiian lobelioids are found within protected TNC preserves such as Waikamoi on Maui and Kona Hema on Hawai‘i island.

From the Pioneer Mountains summer range, pronghorn make a journey which is more than 80 miles each way and is among the longest mammal migrations in the lower 48 states. Using GPS collars, biologists have tracked pronghorn to map their migratory paths. Wildlife managers have used this information to encourage community land-use planning and land stewardship. 

You can spot Pronghorn across the West, but we recommend TNC’s Flat Ranch Preserve near West Yellowstone in the summer!

Grizzlies are omnivores whose diets consist largely of plants including grasses, berries and roots, but they also eat insects and large and small mammals. Historically, they ranged across much of Montana, but as settlements grew, remained only in more remote and forested areas. Today, they use a wide range of habitats where food and security are abundant, including meadows, wetlands, forests and alpine areas. 

Grizzlies can be spotted in both Yellowstone and Glacier National Parks.

Amargosa toads are found in small ponds and standing pools of water at TNC properties in the Oasis Valley, including Torrance Ranch Preserve, 7J Ranch Preserve and the Beatty Narrows. 

The species is incredibly rare and threatened by several factors, including habitat loss and degradation, water diversion, and invasive species.

Many factors have affected this amphibian's habitat, including water withdrawals, river channelization, parasites, pathogens, and invasive fish species. 

The Mimbres River Preserve provides a safe home for the critters with year-round water flows and an off-channel wetland spring habitats.

The Fender's blue butterfly is only found in the Willamette Valley at TNC’s Willow Creek Preserve in Eugene, OR. The species reproduces on just one kind of flower, the Kincaid’s blue lupine. 

This plant has disappeared in the valley due to a variety of causes from urbanization, agriculture, and non-native plant invasions to the suppression of wildfire.

Utah prairie dogs are found only in southwestern Utah and they provide many benefits to people and nature. Their engineered burrows help maintain meadows, which support a variety of plants and animals and allow soil to better absorb water and nutrients. Their burrows are at times used by other critters too! 

Bryce Canyon National Park is a great place to see Utah prairie dogs.

Under normal circumstances, they play a critical role in the local food chain: they feast on the plateau’s pungent sagebrush for at least half of their diet, and raptors, weasels and coyotes feast on them. Human activities such as development and farming have fragmented or separated their native habitat. 

These rabbits are found in Eastern Washington at TNC’s Moses-Coulee Preserve Complex.