The best times to see wild animals in summer are early morning and late evening. The Hayden Valley between Fishing Bridge and Canyon, and Pelican Creek east of Fishing Bridge are prime moose territory. Watch for bison in Hayden Valley, and waterfowl along its Yellowstone River. Watch for elk, bison, pronghorn, and coyotes in Lamar Valley, and for pronghorn in sagebrush flats near the North Entrance. Bighorn sheep frequent Mount Washburn in summer. Elk and occasional bison are seen in the Midway and Upper Geyser Basins. The Lewis River environs near the South Entrance are good elk and moose habitat. Watch for mule deer near Old Faithful, Lake, Canyon, and the areas between the North Entrance and Tower.
Landscapes such as those seen in Yellowstone have long been shaped by fire and not just the cool, creeping ground fires often described as "good" for grass production.
Grizzly and black bears are wild and dangerous. People have been seriously injured, maimed, and killed by both. Bears appear tolerant of people but may attack without warning. Always view bears from a safe distance. FEEDING WILDLIFE IS UNLAWFUL.
Contrary to popular belief, Yellowstone National Park is not one of the hotspots in North America for watching a great diversity of birdlife. What it does offer is an array of birds unique to this area of North America.
Bighorn sheep (Ovis canadensis) once numbered in the millions in western United States and were an important food source for humans. The "Sheepeaters", related to the Shoshoni tribe, lived year-round in Yellowstone until 1880.
Bison are the largest mammals in Yellowstone National Park. They are strictly vegetarian, a grazer of grasslands and sedges in the meadows, the foothills, and even the high-elevation, forested plateaus of Yellowstone.
Bobcats (Felix rufus) are small wild cats with reddish-brown or yellowish-brown coats, streaked with black or dark brown. They have prominent, pointed ears with a tuft of black hair at the tip.
Yellowstone's coyotes (Canis latrans) are among the largest coyotes in the United States; adults average about 30 lbs. and some weigh around 40 lbs. This canid (member of the dog family) stands less than two feet tall and varies in color from gray to tan with sometimes a reddish tint to its coat.
Elk (Cervus elaphus) are the most abundant large mammal found in Yellowstone; paleontological evidence confirms their continuous presence for at least 1,000 years. Yellowstone National Park was established in 1872, when market hunting of all large grazing animals was rampant.
Moose (Alces alces shirasi Nelson), the largest member of the deer family, were reportedly very rare in northwest Wyoming when Yellowstone National Park was established in 1872.
Lynx (Felis lynx canadensis) were reported in the park in the early years of this century. Bailey (1927) reported that "there are said to be a very few Canada lynxes, but we saw no tracks or signs of them," during a July 1926 outing in Yellowstone backcountry by more than 200 Audubon Society members.
Northern Rocky Mountain wolves, a subspecies of the gray wolf (Canis lupus), were native to Yellowstone when the park was established in 1872. Predator control was practiced here in the late 1800s and early 1900s.
The mountain lion (Felis concolor), also called the cougar, is the largest member of the cat family living in Yellowstone.