The largest member of the weasel family is the "street fighter" of the forest.  A wolverine (Gulo gulo) will confront mountain lions or bears to protest its share of a carcass.  The wolverine can be a ferocious animal, and it has been known to chase off larger predators from a carcass.  The wolverine's brawny frame sits low to the ground, and it can weigh as much as 50 pounds.  Sometimes, wildlife watchers will take it for a small bear.  Look for patches of light, grayish hair on the flat top of the wolverine's head, and a brown or yellowish streak down the back that extends nearly to the rump.  Wolverine are so scarce in Yellowstone that any observation should be reported to park biologists.


Undoubtedly, one of the more popular species now found in Yellowstone Park is the gray wolf (Canis lupus). The adult male gray wolf stands 26 to 38 inches high at the shoulder and is usually 40 to 58 inches in length (excluding the tail). Males are 15 to 20 percent larger than females. The weight of gray wolves varies from 40 to 175 pounds. Coyotes are often mistaken for wolves; however, the coyote is actually much smaller at only 20 to 30 pounds in weight.

Although most wolves in North America are a grizzled gray color, they can range in color from tan to pure white or solid black. The gray wolf utilizes its acute senses to survive and flourish in the wilderness. Scientists have estimated that the wolf's sense of smell is up to one hundred times more sensitive than that of a human. One researcher found that a cow moose with twin calves was scented by wolves over four miles away. The sense of hearing is the next most acute of the wolf senses. Wolves can hear much higher frequencies than humans. While the upper auditory limit is 20 kHz for humans, wolves may detect frequencies as high as 80 kHz. Sight is perhaps the least developed of the wolf senses; however, it has been shown that the wolf's sight is at least as acute as that of humans.

Wolves are social animals that hunt, travel, and live in packs. The pack is primarily an extended family unit that is bonded very closely. The pack will consist of a dominant pair of breeding wolves known as the alpha pair, their current offspring, and a few yearlings or other young wolves. There is a definite hierarchy system within every pack with the dominant pair being referred to as alpha and the lowest member in the hierarchy known as the omega wolf. The social order of pack members will change throughout time as wolves sexually mature, reach old age, become ill or wounded, and become weakened. If one of the alpha pair dies or becomes weakened, the next most dominant wolf (called the beta wolf) will take its place. In a pack, only the alpha male and female are allowed to breed. Any attempt at breeding by other members of the pack is met with aggression by the alpha pair. Although the largest documented pack was one of 36 animals in Alaska, the average wolf pack consists of four to seven individuals.

Most Yellowstone visitors are eager to hear the howl of a wild wolf. Wolves do utilize several vocalizations for the purpose of communication. Howls, yips, squeals, growls, chirps, and barks may be used by wolves to express themselves. The best known form of vocalization is the howl which is used for the following reasons: 1) to notify other pack members or other packs of their location, 2) to attract potential mates, 3) to rally the pack before a hunt, 4) to announce alarm at the presence of an intruder, and 5) to express distress (pups often howl when they are stressed). In general, howling is used as a means of long distance communication. For short range communication, wolves use scent marking. Scent marks are used by a wolf pack to advertise its presence in an area.

Gray wolves were reintroduced into Yellowstone National Park in 1995.  Now, years later, the reintroduction has been widely heralded as a great success. Historically, wolves did exist in Yellowstone. According to The Wolf Almanac by Robert Busch, the radio-carbon dating of a bone found in a Yellowstone cave indicates that wolves lived in the area as early as 960 years ago. Unfortunately, the Yellowstone wolves fell prey to the extensive predator elimination programs of the late 1800's and early 1900's. The last wolf to be shot in Yellowstone was killed in 1926. Despite much opposition, the gray wolf was finally reintroduced to Yellowstone National Park 69 years later

Today, Yellowstone visitors can hope for the opportunity to see a wild wolf or at least hear one howling. Although wolf sightings are relatively uncommon in the park, all visitors can enjoy the feeling that comes with knowing that the wolf is once again part of the Yellowstone wilderness that is so precious to us all.

Where to find them
Wolves are known to exist in all portions of Yellowstone National Park; however, Lamar Valley, early in the morning or near dark, is certainly your best bet.

Trumpeter Swan

The Trumpeter Swan (Cygnus buccinators) is the largest of waterfowl in North America, and easily the biggest flyers in Yellowstone. The wingspan of males (cobs) can reach seven feet. Cobs weigh between 25 and 30 pounds, while females (pens) weigh 23 to 27 pounds. The trumpeter is generally bigger and heavier than the eagle.  The trumpeter swan, native only to North America, was once headed toward extinction south of Canada. By the mid-1800s, market hunters had almost exterminated the trumpeter. They were slaughtered in great numbers for their plumage, used to decorate ladies' hats. By the 1830s, fewer than 100 birds remained. Congress set aside a wildlife refuge west of Yellowstone to facilitate trumpeter recovery. In recent years, the Park Service has also taken measures to assist the trumpeter, including nesting islands to protect nests from coyote predation.

Where to find them
Look for Swans along the Madison and Firehole Rivers. There is almost always a nesting pair on the Madison and depending on the time of year watch for cygnets. The Yellowstone River just south of Canyon is another good spot to look for Swans.


The Pronghorn (Antilocapra americana) is the fastest North American land animal, capable of reaching speeds of up to 60 miles per hour. The pronghorn's speed is its main defense against predators. The newborns, for the first few days of their lives, are vulnerable to coyotes. The mother guards them closely, and they often times remain perfectly still, their dappled gray coat blending in with the grasses and shrubs, so that predators cannot detect them. By the end of their first week, they are running about, and soon are young speedsters themselves. As adults, their coats turn brown with distinctive white patches on their stomach and rump. Up to 40 million of these graceful animals used to roam North America, but hunting and the settlement of the West reduced their numbers to as few as 20,000 near the turn of the century. There are about 5000 present in the Yellowstone area today.

Where To Find Them
Pronghorn are found mainly in the Northern section of the park. One of the best places is the one-way dirt road that runs from Mammoth Hot Spring to Gardiner. There are almost always some at the north entrance station near Gardiner. Also look for them on the road between Mammoth Hot Springs and Tower Junction and in the Lamar Valley area.


The prickly pear of the mammal world, the porcupine (Erethizon dorsatum) carries some 30,000 quills in its quiver, and each barbed quill can deliver a stinging reminder that the animal prefers to be left alone.  However, contrary to myth, a porcupine cannot "shoot" its quills at intruders.  The surest signs of porcupine presence are their tracks - the front tracks show four toes with claws while the back paws reveal five claws, and the cat-like feces the animal produces when it browses on the bark of trees.  Porcupines are widely dispersed in the forests of Yellowstone National Park, and are common along stretches of highway that dissect stands of old-growth forest.

Where To Find Them
Porcupines can sometimes be seen along the roads that run through the older forests of Yellowstone.  One of the best locations to see a porcupine is along the road between Mammoth and Tower Junction.

Mule Deer

Mule deer (Odocoileus hemionus), also known as black-tail deer, are ideally suited to the rugged slopes of the Rocky Mountains. A large number inhabit the park in summer, but most migrate to lower elevations, or "winter range" outside the park in the winter. Like the elk and bison, mule deer were reduced to dangerously low numbers in the mid-nineteenth century due to over-hunting. At the turn of the century, Yellowstone served as a sanctuary and continues to protect them from hunters within the park's boundaries.

Three features make the mule deer easily recognizable: its oversized ears, its black-tipped tail, and its unique way of jumping and landing on all four feet at once. Mule deer are browsers with a highly varied diet. Studies have documented mule deer in the Rockies that eat over 600 different species of plants. They feed on grasses during spring and summer, and on branches of trees and shrubs in winter. Palatable grasses and shrubs now flourish in many of the areas burned by the 1988 fires.

Where to find them
Mule deer are not seen often in Yellowstone, but can be found in many locations. Most often, they are seen along the Madison River and in the Mammoth Hot Springs area. They are also often seen in the Blacktail area between Mammoth and Tower Junction.

Mountain Lion

The mountain lion (Felis concolor), also called the cougar, is the largest member of the cat family living in Yellowstone.  Mountain lions can weigh up to 200 pounds, although lions in Yellowstone are thought to range between 140 and 160 pounds for males and around 100 pounds for females.  Two to three kittens may be born at any time of year, although most arrive in summer and fall.  For reasons that are not clear, only about 50 percent of kittens survive their first year.  The current population of lions in Yellowstone is estimated to be 18-24 animals and is thought to be increasing.  Mountain lions are rather secretive, consequently, most visitors are unaware of their existence in Yellowstone.  Lions live throughout the park in summer.  In winter, difficulty of movement and lack of available prey causes most lions to move to lower elevations.  Lions are territorial and will kill other lions.  The dominant animals reside in the northern range areas of the park where prey is available year-round.  Mountain lions prey chiefly upon elk and deer, although their diet probably varies based upon opportunity, porcupines provide an important supplement to the lion's diet.

In 1987, the first study of mountain lion ecology was initiated in Yellowstone National Park.  The research documented population dynamics of mountain lions in the northern Yellowstone ecosystem inside and outside the park boundary, determined home ranges and habitat requirements, and assessed the role of lions as a predator in the ecosystem.  In recent years in other areas of the West, mountain lions have occasionally attacked humans.  No documented lion/human confrontations have occurred in Yellowstone.

Where To Find Them
In Yellowstone, it's improbable that you will see mountain lions from the roadside and even rarer to see from the roadside in wide-open country without trees or side canyons into which they can escape.  However, sightings of lions have been more frequent in the Lamar Valley and along the Yellowstone, Madison, and Gallatin river drainages.  Specifically, sightings have been reported along the park highway east of Lamar Valley and the highway over Sylvan Pass outside the east entrance, and in the Tower-Roosevelt area.  Perhaps, the best bet to see a lion is in Lamar Valley.

Mountain Goat

Mountain Goats (Oreamnos americanus) are only occasionally seen in the high mountain peaks in Yellowstone National Park.  Mountain goats have brawny frames.  They are sure-footed, with long, yellowish white fur and black spiked horns.  Males stand about 3-1/2 feet high and weigh between 120 and 250 pounds, while the females, which also have horns, are slightly smaller.  Mountain goats are comfortable on steep, rocky ledges and mountain peaks, because their hooves are adapted for climbing and maneuvering in such places.  During the past thirty years, one to fifteen goats have been reported at least seventeen times in the park, and on five occasions near the park.  Of the seventeen in-park observations, six were in the northwest corner and eleven were in the northeast corner of the park.

Where To Find Them
In Yellowstone National Park, seeing a mountain goat is a rare event.  The northeast corner of the park, on the cliffs flanking Baronnette Peak (north of the highway) and Abiather Peak (south of the highway) provide the best opportunities.  If you see a goat, write down the location and report it to a park ranger.


Some visitors will have the opportunity to view a wild moose. The moose (Alces alces) is the largest member of the deer family with mature bulls weighing more than 1,000 pounds. The bull moose produce large palmate antlers which are shed annually. Although cow moose do not have antlers, both bulls and cows do have a bell which is a growth of skin and hair that hangs down from the throat. Calves are born in the spring and remain with the cow for a year. Cow moose will aggressively protect their young from any perceived threat.

Moose browse on twigs and leaves. Willows are an important food source, and moose also feed on submerged aquatic plants. Moose are dark in color ranging from brown to black. The moose also has long legs which are an adaptation to the thick marshes where it feeds and to a habitat that is covered by deep snow much of the year.

 The moose is normally a reclusive animal. You are most likely to see one in the streams, marshes, and willow thickets along the road between Mammoth Hot Springs and Norris. Moose may also be observed in the Fishing Bridge/Yellowstone Lake area, the Lamar Valley meadows, Hayden Valley, and along the east entrance road. Occasionally, they can be observed feeding or resting while partially submerged in water.

Yellowstone visitors should remember to never approach a moose. Though sluggish in appearance, they are fast. A cow moose protecting its young can be a very dangerous animal.
If you plan to visit Yellowstone National Park this year, keep an eye out for moose in the areas listed above. If you do observe a moose, remember to keep a safe distance between you and the animal. Never approach any wild animal as your personal safety and the welfare of the animal may be threatened.

Where to find them
Look for moose among the willows in Willow Park, just south of Mammoth Hot Springs. Another good area is just south of Canyon and the Lake area. On occasion, they can be seen in the Madison and Firehole rivers. The east side of Lamar Valley is another good spot.

Grizzly Bear

The Grizzly Bear (Ursus arctos horribilis) is a powerful predator, capable of out sprinting a horse, and weighing as much as 350-600 pounds. Grizzlies are omnivorous, meaning they eat both meat and plants. In Yellowstone, grizzlies feed on elk, trout, bison carrion, pine nuts, grasses, roots, and berries. Certain characteristics distinguish grizzlies from black bears. The grizzly is larger, both in girth and weight. The grizzly's coat ranges from tawny cinnamon to light brown or even black. Some grizzlies are flecked with recognizable "silver tips," creating the "grizzled" look. A feature also associated with grizzlies is the shoulder hump, and area of well- defined muscle. Another is his dish-shaped face. Grizzlies hibernate in dens during the winter. This is when the cubs are born. Emerging from their dens in the spring with one to three cubs, the mothers are very protective. They will not hesitate to charge intruders which they perceive as threatening their cubs.

Where to find them
Grizzly Bears range throughout Yellowstone but are most often seen in and around the Dunraven Pass area and just past the turn off to Mount Washburn. Another good area is across the Yellowstone River in Hayden Valley and in the Fishing Bridge area. Also in Lamar Valley. A good pair of binoculars or a spotting scope is a must.

Grizzly bears are active primarily during the night and at dawn and dusk.  Look for grizzlies with binoculars or a spotting scope in open meadows around sunrise or sunset.  Grizzlies are often seen from the road in the Lamar Valley, from Tower to Canyon, Lake, and Fishing Bridge.   They are also seen along the road to the East Entrance.  In the backcountry, grizzlies are most often seen south and east of Yellowstone Lake and in the Gallatin Mountains in the northwest corner of the park.

Red Fox

The Red Fox (Vulpes vulpes) is the shyest wild canid in the Yellowstone region and seldom seen, when compared to wolves or coyotes.  Although red foxes are abundant in the lower agricultural river valleys outside the park, the foxes of Yellowstone are far more discreet.  Studies suggest that the higher elevations of Yellowstone and adjacent mountains may actually be home to an endemic species of fox that exists in isolation from other native red foxes and those introduced to the continent by Europeans.

Red Foxes are common throughout most of North America, and the animal's "cunning" ability to outfox hunters and fur trappers is legendary.  Night hunters that prowl the forest edges and meadows, these omnivores have smaller territories than coyotes but they will hunt across wide areas nonetheless.  Wildlife watchers shouldn't have a problem differentiating between red foxes and coyotes.  An adult fox weighs about 15 pounds, perhaps half the weight of a small adult coyote.  Foxes also have a classic long, slender snout.  Unlike wolves and coyotes, foxes rarely howl or sing as a form of gregariousness.  What sets foxes apart, of course, is the color of its fur.  The fox has a spot of white on the tip of its fluffy black and red tail.  The underside of its body, from neck to posterior, is covered by a creamy white fur, and its paws are reddish blond.  As with black bears, red foxes take on hues other than the color for which they are primarily known.

The red fox generally subsists upon a variety of rodents but has other dietary staples such as grasshoppers and berries.  In learning more about foxes, we begin to understand how predators interrelate.  The reintroduction of wolves to Yellowstone may impart some long-term benefits for foxes by producing a lower coyote population, which is a fox competitor.  Also, carcasses left behind by wolves might benefit foxes too.  Never, under any circumstances, approach or attempt to feed a fox.  The animal will bite if provoked and it can carry rabies.  However, no Yellowstone canid - fox, coyote, or wolf has tested positive for rabies since the park was founded in 1872.

Where to find them
The timid nature of foxes means they are less visible from the road than coyotes.  Sightings are infrequent and often seasonal, with most occurring in winter, spring, or autumn around Canyon Village.  In meadows that roll away from the Grand Canyon of the Yellowstone River, foxes are occasionally spotted from the roadside as they hunt at dusk and dawn.  Red "mountain" foxes are also sighted occasionally along the slopes of Mount Washburn, which rise above Dunraven Pass, and in the northeastern corner of the park on the slopes of the Absaroka and Beartooth Mountains above the towns of Silver Gate and Cooke City.


The elk (Cervus elaphus) is the most abundant of the large mammals of Yellowstone National Park. Often times reaching the size of a large horse, elk can be seen throughout Yellowstone year-around. The cows and calves oftentimes travel in large groups of a hundred or more during the summer months, while the males tend to travel by themselves or in very small groups, feeding on grasses and tree twigs. During the summer months, Elk can usually be seen in the Lamar Valley and in the northwest sector of the Park. The Mammoth and Gardiner area, located at a relatively low elevation, provides forage for elk throughout the year and gives the visitor of any season ample viewing opportunities. Nonetheless, elk are liable to be spotted anywhere in the Park, and some of the mature males are majestic in stature with tremendous antler spreads. The mating season takes place in the fall, and the bulls lock antlers in fierce competition, their bugles ringing through the air, as they battle for a harem of cows. During the winter months, the weak and the young sometimes succumb to the harsh weather. Both grizzlies and wolves prey on elk, seeking the young and the weak who may lag behind the rest of the herd. Watching a grizzly stalk a herd of elk is a special privilege that only a fortunate few witness.

Where to find them
Some of the best places are along the Madison, Firehole and Gibbon Rivers. Also in the Upper Geyser basin. Also in Hayden and Lamar Valleys. The are often seen in and around the Mammoth Hot Spring area. During the fall elk rutt look for them in Madison and Gibbon meadows and just North and East of Mammoth Hot Springs.


Having survived the same extermination campaigns that eliminated wolves from the park between 1910 and 1930, coyotes (Canis latrans) have by default become the predominant canine predator. The restoration of the wolf in Yellowstone has changed this status. Although the coyotes fur varies in color, the majority of adults have grizzled gray coats with a white underbelly, bushy tail, and reddish hair on their legs. On average, coyotes weigh between 30 and 40 pounds, about half that of a wolf. Compared to the wolf, coyotes are dainty, with their heads, muzzles, legs and feet far less massive than a wolf's. Coyotes favor small rodents and rabbits as their main diet, although they have been known to work together in bringing down young, sick or injured larger mammals, such as elk, or deer.

Where to find them
Coyotes roam throughout the Yellowstone region and can be seen most anyplace in the park. Areas where they are most visible are along the Madison, Firehole and Gibbon Rivers. Lamar Valley is a good place but the introduction of the wolf has displaced many in that area. Hayden Valley is another good spot.

Black Bear

Black Bears (Ursus americanus) are the most numerous member of the bear family in North America, and are found from the Pacific to the Atlantic coast. There are an estimated 500-600 black bears inhabiting Yellowstone National Park.

Black bears are not all black; their coats can be cinnamon, blonde, brown or black. Brown -colored black bears are sometimes mistaken for grizzlies. Black bears are smaller than grizzlies: adult males weigh between 200 and 600 pounds, females between 150 and 400 pounds. The black bear's rump is higher than it's shoulder, and it's head is "Roman-nosed", rather than the grizzly's dish shape. Black bears feed on a variety of grasses, roots, berries, and other plants, in addition to small rodents and animal carcasses.

Where to find them
Black Bears can be seen most anywhere in Yellowstone at anytime. They are often seen around the Tower area and in the Blacktail plateau area between Tower and Mammoth Hot Springs. Lamar Valley is another good area and along the Madison and Firehole rivers.


The Yellowstone bison (Bison bison) story covers more than one hundred years of struggle and conflict surrounding one of America's most majestic animals. In the early 1800's, an estimated 65 million bison roamed throughout the continent of North America. However, market hunting and poaching had a devastating effect on the bison population; and by 1890, fewer than 1,000 remained! Even with the establishment of Yellowstone National Park, protection and sanctuary for the bison did not occur until the U.S. Army arrived in 1886 to protect the park's resources.

Due to protection and manipulative management (transplanting bison to different parts of Yellowstone), there were approximately 1,500 bison in Yellowstone National Park by 1954. Beginning 1968, the manipulative management of Yellowstone bison was discontinued and the population was allowed to fluctuate based on environmental conditions (i.e. winter weather, food availability, etc). In the 1970's and 1980's, there were a series of cool, wet summers followed by mild winters. These conditions allowed for an abundance of grasses for the bison to feed on and a reduction in the winter mortality rate.

In addition, snowmobiling in the park has helped more bison survive winters since the groomed roads cut down on the amount of energy that a bison uses to travel when compared to traveling through deep snow. By the winter of 1996 to 1997, there were approximately 3,500 bison in Yellowstone National Park. The bison (often referred to as buffalo) is truly a majestic animal. An adult bull bison may be six feet tall at the shoulder and weigh 2,000 pounds. Females look like the males except that they are smaller and have more slender horns. Bison mate from July through early August, and the calves are born in April and May. During the spring and early summer, new-born calves can often be viewed in the Firehole area and Lamar Valley. Although viewing the young calves can be an exciting experience, it is very important that you do not get too close to the animals for observation or photographs. Bison may appear big and slow, but they can run up to 30 miles per hour. Yellowstone visitors are gored every year, because they venture too near in attempts to photograph the animals.

Where to find them
Bison are almost always on the move and are seen in different areas during different seasons. Probably the best spot is in Hayden Valley along the Yellowstone River. Some other spots are along the Madison, Firehole and Gibbon Rivers. Look for bison in the Fountain Flats area and the Mud Volcano area, also in Lamar Valley. Lone Bulls are often seen around the Lake Hotel and Fishing Bridge.

Bighorn Sheep

Although Bighorn sheep (Ovis Canadensis) prefer the grasses and sedges found in open meadows, they find safety on rocky ledges and rugged terrain. They are nimble and have a well-developed sense of balance, allowing them to seemingly walk on sheer cliffs and mountain sides. Newborn lambs are prey for eagles, mountain lions and bobcats. The tremendous horns of the male sheep are for the purpose of defending from predators and in battling among themselves for control of the harem. Battling rams will get a running start and crash head first, resulting in a sound similar to a rifle shot.

Where to find them
Bighorn are not often seen in Yellowstone, mainly because of the limited areas they are found. Look for them along the cliffs and steep hills on the road from Mammoth to Gardiner. Rocky outcrops in the Lamar Valley are also good places to look.


The wildlife symbol of industriousness, the dam-building beaver (Castor canadensis) has the power to shape the future of small streams in Yellowstone National Park.  Known as a busy logger with curved buckteeth, the beaver can be identified by its webbed hind feet, lush brown coat, and paddle-like tail.  Beaver presence is indicated by dams, domed lodges partially immersed in water, and tree stumps gnawed to a conical point.  You'll find them hard at work around dawn and dusk.

Where To Find Them:
Beavers can be found throughout Yellowstone National Park in areas located near a body of water such as lakes, ponds, rivers and streams.  Areas near Yellowstone Lake, the Yellowstone River, the Lamar River, and the Madison River offer some excellent opportunities to view the beaver in their natural habitat.

Bald Eagle

Bald eagles (Haliaetus leucocephalus) are one of two species of eagle in Yellowstone, the other is the golden eagle. They are raptors and carnivores, seeking a diet of fish, waterfowl, rodents and small mammals. They also scavenge from the carcasses of large animals such as elk and bison. Yellowstone's most important role for bald eagles may be its use as a seasonal feeding area for migratory eagles passing through in the spring and autumn.  Several hundred eagles make a temporary stopover along the trout-rich environments of Yellowstone Lake and the Madison, Yellowstone, and Snake Rivers on their way to wintering areas in the Pacific Northwest or central-southern Rocky Mountains.

Where to find them
Bald Eagles are frequently seen along the rivers in Yellowstone, and Madison is one of the best spots early in the mornings. Another excellent place to view bald eagles is just south of Canyon Village along the Yellowstone River.

Yellowstone National Park is a diverse ecosystem that provides excellent habitat for a diverse group of living organisms that range from the tiniest microorganisms inhabiting the geothermal features to the park's large bison grazing in the valleys.  Yellowstone is home to many different species of wildlife including grizzly and black bears, wolves, moose, elk, pronghorn, bighorn sheep, mountain goats, foxes, wolverines, eagles, hawks, falcons, trumpeter swans, squirrels, marmots, fish, and much more.  In fact, Yellowstone is one of the best places in the world to view wildlife because the animal density is so high that visitors often can view them from the road while driving through the park.  As you enjoy the majestic wildlife of Yellowstone during your next visit, remember that these creatures are wild animals.  They can be extremely dangerous if they feel threatened, so always maintain a safe distance from wildlife.  The minimum recommended distance is 100 yards (91 m) for larger animals such as bears, wolves, bison, and elk.  May and June are great months to view newborn wildlife such as elk and bison calves.  If you're planning a trip to Yellowstone National Park, remember to bring your camera!  Review this page to learn more about some of the wildlife that can be found in Yellowstone National Park.   

Yellowstone National Park