Wildlife Habitat

Despite Sublette County’s abundance of public land, private land provides much of the habitat that supports diverse wildlife populations is located on private land. River valleys and bottomlands harbor wetlands, riparian corridors and critical winter range. Runaway land prices squeeze out the ranching families who have lived with this wildlife for generations. Subdivision and other inappropriate development increasingly fragment landscapes into tiny, unraveling remnants of ranches.

Bighorn Sheep
Rocky Mountain bighorn sheep are well adapted to extreme elevation and temperature. They live year-round in the high rugged rocky cliffs. During winter, small herds can often be seen along the Hoback Canyon on US Highway 191 in the Gros Ventre Mountains.

Rocky Mountain Elk
The Rocky Mountain elk is considered to be one of Wyoming's premier big game species. An estimated 75,000 elk live in the state, and there are eleven elk winter feedgrounds in Sublette County. Most Rocky Mountain elk migrate between high elevation summer ranges to lower winter ranges and back each year. Winter snows make food sources hard to reach prompting herds to move to locations where snow depths are lower, plants are easier to reach, and there is protection from winter storms. These winter range areas typically have special regulations restricting human presence that would disturb them during the stressful seasons. In the spring, snowmelt and spring green-up of grasses cause the herds to move upslope into the higher elevations and forests.

Pronghorn
The pronghorn (Antilocapra americana) is not a true antelope but in a family by itself (Antilocapridae). It is native only to North America. The pronghorn is the only North American big game animal that has branched horns, from which its name derives. Pronghorns have true horns — derived from hair — not antlers. The horns have an outer sheath of fused, modified hair that covers a permanent, bony core. Pronghorns shed the hollow outer sheath each year in October or November and grow a new set by July. Pronghorn, more closely related to goats than antelopes, are common in the open grassland and sagebrush hills of Sublette County. They typically roam the arid sagebrush plains and forest edges in groups, which can be quite large during spring and fall migrations. Their keen vision and speed are unmatched by any other North American mammal, allowing rapid escape from predators. Pronghorn shed the outer shell of their horns every year but keep the bony core. Both males and females may have horns. In the spring, it is common to see does with twins in the open sagebrush plains. Pronghorn are vegetarian and eat a diet of grasses, forbs, sagebrush, and woody browse.

Moose
The majestic moose is always a thrilling sight, and a true symbol of the mountain west. While its appearance seems awkward, in reality moose are surprisingly agile and can rapidly traverse terrain that appears impassable. Moose can grow to over 1,400 pounds in weight and up to 7-feet tall at the shoulder. While they are often depicted eating in marshlands, they spend most of their time in heavily forested areas and more than half of what they eat is wood.

Mule Deer
Mule deer are very common in Sublette County, but white-tailed deer also reside here in small populations. One of the most interesting characteristics of the mule deer is its unusual gait. They often can be seen bounding and landing with all four legs simultaneously so that it looks like the animal is hopping along on all fours. Mule deer are usually silent, but when startled can be heard snorting or grunting as they move away. Often, they will give one last glance at whatever disturbed them before disappearing over a rise. Mule deer tend to feed at dawn and dusk and visitors are often rewarded by seeing them on evening rides along back roads in the open sagebrush countryside. White-tailed deer are easily differentiated from mule deer by the distinctive trait of raising the tail when alarmed, showing the bright white underside of the tail which “flags” back and forth as the deer runs swiftly away. Males of both species lose their antlers each year and grow them again during the spring and summer to have them reach full spread in time for the fall mating season.

Bears
Both black bear and grizzly bear are found in the remote forests in Sublette County, typically in the higher country. Both are very seldom seen, but without a doubt are the species visitors are the most concerned about. Black bears are typically peaceful, but may be encountered more during years of drought when lack of natural food supplies brings them to areas of human presence, such as campgrounds, in search of food. Grizzly bears inhabit the upper Green River area where they range from Yellowstone National Park in search of food. Bears pose problems for ranchers who have faced cattle losses due to depradation.

Fish
Aside from its world-class trout fishery status, Sublette County is also home to a species of fish found nowhere else in the world, the Kendall Dace, found in the Kendall Warm Springs in the Upper Green. They are listed on the Endangered Species List. This small, minnow-like fish was discovered in 1934 in the short section of warm springs that flows over a waterfall into the Green River. The adult fish are only between 1-2 inches in length and have a flat belly with an olive-black color. Their sides are a grayish green, with a dark lateral stripe running down the sides which is thought to help with camouflage. They have dark speckles or blotches on the body, and their fins are plain.