Wyoming’s expansive landscapes are home to diverse wildlife, including prominent deer populations. Two primary deer species inhabit Wyoming: the widespread Mule Deer and the more localized White-tailed Deer.
Wyoming’s Mule Deer
Mule deer (Odocoileus hemionus) are distinguished by their large, mule-like ears. They have a brownish-gray body, a gray face, and a black forehead or mask. A notable feature is their white rump patch and a small, rope-like tail tipped with black. Male mule deer, known as bucks, grow antlers that bifurcate, or fork, multiple times. Adult males can reach weights of up to 250 to 300 pounds, while females, or does, typically weigh up to 175 pounds.
This species occupies nearly all habitats across Wyoming, from lower elevation sagebrush deserts and creek bottoms to mountainous regions. They are found throughout western North America and are the more widespread deer species in Wyoming. Some populations undertake extensive migrations, with the longest known mule deer migration in the continental United States spanning 150 to 240 miles from the Red Desert to the Hoback Basin.
Wyoming’s White-tailed Deer
White-tailed deer (Odocoileus virginianus) have smaller, more rounded ears. Their antlers are structured with a main beam from which individual points project forward. Their most recognizable feature is a broad, flag-like tail, brown on top but entirely white underneath.
These deer are generally smaller than mule deer, with a typical buck weighing between 150 and 200 pounds. Their coat is often reddish-brown in summer, transitioning to gray-brown in winter, with white patches on their throat and belly. White-tailed deer in Wyoming are primarily found in riparian areas, agricultural lands, and lower elevations with ample cover. While distributed throughout the state, their concentrations are highest in the northeast and southeast corners, and they are less common in western Wyoming, often confined to river and creek drainages.
Key Differences for Identification
Distinguishing between mule deer and white-tailed deer involves observing several features. Mule deer have noticeably larger, mule-like ears, while white-tailed deer have smaller, more rounded ears. Antler structure provides another clue; mule deer antlers exhibit bifurcated branching, while white-tailed deer antlers have points that grow off a single main beam.
The appearance of their tails offers one of the most reliable distinctions. Mule deer have a small, rope-like tail with a black tip, set against a prominent white rump patch. White-tailed deer have a broad tail that is brown on top but conspicuously white underneath, and they often raise this tail like a flag when alarmed or running.
Their gait also differs significantly; mule deer typically employ a stiff-legged, bounding motion called “stotting,” where all four feet push off and land simultaneously when startled. White-tailed deer, however, tend to bound or gallop when fleeing. Mule deer often have a white facial mask with a darker forehead, while white-tailed deer usually have a brown face with subtle white rings around their eyes and mouth.
Other Notable Wyoming Ungulates
Wyoming’s diverse ungulate population includes other large animals sometimes mistaken for deer. Elk (Cervus canadensis) are the second largest members of the deer family. They are characterized by their tan or light brown bodies, dark neck manes, and the large, branched antlers of males. Adult bull elk can stand around 5 feet tall at the shoulder and weigh up to 700 pounds.
Moose (Alces alces), the largest members of the deer family, are also found in Wyoming, with the Shiras Moose subspecies present. These animals are identifiable by their substantial size, dark brown coats, long legs, large ears, bulbous muzzles, and a dewlap hanging from their throats. Bull moose can weigh up to 816 to 1,000 pounds and stand up to 7.5 feet tall at the shoulder. They are often observed alone in marshy or riparian areas.
Pronghorn (Antilocapra americana) are another unique North American ungulate often seen in Wyoming’s open grasslands. Despite common misidentification as antelope or deer, pronghorn are the fastest land animals in North America, capable of speeds up to 60 miles per hour, and possess horns that are shed annually, unlike true antlers.