Wildlife of Jackson Hole, WY

Interested in wildlife around the Bentwood Inn? Check out these “wildlife fact sheets” Kelly created!

Buffalo

Kelly Campus of Teton Science Schools

Beaver Information Fact Sheet

Scientific Name: Castor canadensis
Order: Rodentia
Family: Castoridae

• Second largest rodent in the world (first is capybara of South America)
• Range: found all over North America, and parts of Europe and Asia
• Includes 25 species
• Descendants of prehistoric Castoroides of the Pleistocene Ice Age, giant beavers up to 700-800 pounds!
• During their life span of up to 12 years, beavers never stop growing

Physical Characteristics
• Breathes air, but spends much of its time under water
• Well adapted for water:
Eyes: have third, clear “nictitating” eyelid which acts as goggles under water
Ears: valvular; can be closed under water
Nostrils: also valvular, can close nostrils when under water
Coat: waterproofed by castor glands which secrete oil, and thick underfur 2 cm with long, outer, heavy guard hairs 6-7 cm. long
Lungs and liver: over-sized and extra-efficient, so beaver can hold breath under water for long periods of time without passing out or dying
Cheeks: so loose they can be sucked together behind teeth, which allows beaver to strip bark under water without gagging

Diet
• Entirely vegetarian
• Eats buds, leaves, fruits, seeds, bark
• During winter, subsist solely on bark
• Prefer Aspen, Birch, Willow, Poplar, Alder, Maple, Cottonwood
• Summer/Spring food: grasses, ferns, roots, almost all water plants
• Large gland at upper end of stomach secretes enzyme to help reduce woody, plant material to food

Breeding and Mating
• Mate for life
• Litters of “kits” are born each May or June, after 100-day gestation period; litter varies between 3-9 kits
• Until one month, kids stay in lodge with an older family member always present; because their small bodies are buoyant; they would not be able to re-enter under the lodge because all entrances are under water
• Kits stay at lodge for 2 years in which they leave to build their own dwellings

Behaviors:
• Can be submerged for about 3 minutes at a time; have been known to stay under for half and hour; can swim half a mile under water
• They swim using back feet either alternating kicking or in unison; front feet are balled up at the chest, not used when swimming
• Spend a fair amount of time grooming; the coat would not be waterproof if beaver failed to keep clean, straightened, and oiled (using secretion from castor glands, spreading on fur with paws)
• Mostly nocturnal animals: works from 5-8 p.m. to 12 hours later
• Create scent-mounds to aware other beavers of territories; build mud-mound, and secrete substance from cloaca and castor glands

Communication:

• Partly accomplished by rapid clicking of the teeth
• Slap tail to alert one another of danger

Predators:

• Wolves, coyotes, bears, lynx, wolverines, otter
• Guard against predators by having only openings to lodge under water
• When out of water, they work where they are able to smell land predators
(i.e. down wind)

Benefits to others created by Beavers:

By creating dams with their lodges other habitats are created for animals such as birds, deer, foxes, frogs, turtles, otters, ducks, muskrats, and water insects. Also, they create rich meadows where once were ponds and their dams save soil which becomes rich silt.

Bison Fact Sheet

Scientific Name: Bison bison
Order: Artiodactyla
Family: Bovidae

• Found in North America
• Different from buffalo relative (wisent) found in Europe
• Largest terrestrial mammal native to North America
• Habitat: occupy grasslands and meadow communities, also shrub-grass and desert grassland communities

Physical Characteristics:
• Largest wild animal on continent
• Size (avg.): 65-80 in. at shoulder
• Weight (avg.): 1,500 lbs. (male); 1,000 lbs. (female); out-weigh even the moose
• Very poor eyesight, good hearing, extremely good sense of smell
• High-bumped shoulders, massive head, muscular neck
• Narrow hindquarters
• Forequarters, neck and head wrapped in light brown, shaggy mane; descends to knees and extends to just behind shoulders
• Rest of body covered in short, darker brown hair
• Short, stout horns, curve upward and outward from sides of head, up to two feet long; both male and female have horns; do not shed
• Short tail with long hairs at tip
• Color: dark chocolate to blackish, pales in winter, yellow-brown by spring

Habits:
• Bison can be hasty, nervous, testy, easily tempered to charge or flight
• Among most gregarious animals on Earth; seldom found alone
• In general, cows and adult bulls live separately, except during mating season

• Wallow in mud or dust to rid coats of itchy
Good swimmers: take to water readily, but ice can be dangerous for them, historically, herds have drown trying to break through

• They typically travel around 5 m.p.h., but can reach up to 32 m.p.h. when startled
• Rub against tree, rock, or even other bison to help remove hair when shedding
• Use bulky heads to clear snow in winter to search for grasses
• Sounds: bleats, grunts, moans, male: loud to show dominance, short, harsh bark for threats, shrill whistle when angry

Diet:
• Nonselective grazing animals, live primarily on sedges and grasses; also herbs, leaves, shrubs, twigs
• In winter, forge for whatever plant matter is available under snow
• Normally have winter and summer ranges, but are restricted today, now are often helped through winters by offerings from humans
• Usually graze in morning and evenings, rest during the day
• Because grass is difficult to digest, Bison have a four-chambered stomach. They chew then swallow, then while resting, they will bring up a wad of food, or “cud”, to rechew and swallow.

Mating/Reproducing
• Bison become sexually mature at 30 months and breed between late July to late August
• Their gestation is 285 days and one calf is born between April and June weighing 31-40 lbs., with reddish color.
• Their life span can be 20 years or more

Predators: NONE, normally; occasionally grizzly bears

In existence today there are approximately 40,000 bison living on preserves or ranches

Your best chances of seeing a herd of bison are to drive to a popular grazing spot in the Gros Ventre Range. Drive north on Hwy 191 (N. Cache Ave) toward Grand Teton National Park. Turn right on Gros Ventre Rd and drive approximately one or two miles to see large herds grazing in the mid-late morning and afternoon hours.

Black Bear Fact Sheet

Scientific Name: Ursus americanus cinnamomum
Order: Carnivora
Family: Ursidae

Black bears are the most common bears in the U.S. Their range extends from Northern Mexico and Northern California to Alaska and across to the Great Lakes, Newfoundland and Appalachians; isolated populations include Florida to Northern Gulf Coast. Their habitat is primarily forests and woodlands.

Physical Characteristics:

• Medium sized: average adult about 300 lbs., between 4.3 and 5.9 ft from nose to tail, 31 to 37 inches at shoulder
• Color; not always black; ranges from black to brown to almost blond; they shed their coat in July.
• Foot: toes are spread apart in an arc-like shape: good for climbing trees; big toe is located on the outside of foot for better balance
• Claws are no longer than 1.5 inches
• Noses are long and straight, very keen sense of smell
• Largest ears of all bears, rounded and set back on heads, better hearing than humans
• Near-sighted, like all bears
• Plantigrade: walk on flat feet
• 25 m.p.h. is not an unusual speed for short distances
• Life span can be over 15 years; 20 years is unusual
• Tracks very from crisp to indistinct due to hair under feet

Behaviors:
• Largely solitary animals, except when mating, and when mother has cubs
• Live in forested areas, climb trees readily when in danger
• Favor mixed habitats
• In many areas, black bears are nocturnal
• Adaptable animals that can live close to civilization if not hunted
• Mark trees often, perhaps as a territorial action, though are not exceptionally territorial
• Vocalizations include “jaw dropping” or teeth snapping which accompanies bluffs, and the sudden expulsion of air “wolfs” when senses danger
• Enjoy rubbing, to itch and remove hair; and bathing, to clean and keep cool
• As a rule, they generally avoid grizzly bear

Hibernation:
• Find caves or existing holes for winter den (sometimes even hallow trees)
• Drag leaves and tree branches for bed
• Around October, retire to den for up to six months
• Den alone, except for mother with cubs
• Enter a deep sleep in winter (not a true hibernation) because they are easily aroused.
• Heartbeat drops from 40 beats per minute (regular sleeping rate) to 8 beats per minute
• Body temperature drops to 4 to 7 degrees Centigrade

Diet:
• Omnivorous, though largely vegetarian: have 42 varied teeth for both meat and plant material
• Opportunists, foragers, flexible eaters
• Spend much of time slowly roaming, grazing (diet is around 80% vegetarian)
• Food requirement is around 11-18 lbs. per day
• Diet consists of sedges, grasses, herbaceous plants, berries, nuts, honey, wild onions, insects, roots, small rodents and their food caches, tubers, carrion, beetles, larvae, cambium (underside of bark), fish
• Are both scavengers and occasionally predators: eat carrion in spring and occasionally hunt weak elk or deer, will eat other dead bears
• Most meat comes from small animals: are adept to flipping rocks and logs to uncover mice and insects
• Sometimes eat fish but are not as good as grizzlies at fishing

Mating and Cubs:
• Females can breed at 3.5 years old but are not usually successful until 4.5 years
• Estrus lasts up to two months, with prime mating season in late June and early July
• Courting consists of male following female, eating less, and attending to her until she is ready to mate
• Copulation lasts for up to 30 minutes

• Promiscuity is not uncommon, though a pair may stay together for the mating season
• Gestation period is 200-220 days; she gives birth to 1-3 cubs in January or February in her den, after seven months of pregnancy
• At birth, cubs often weigh less than half a pound, and are 1-2 inches long: benefit of delayed implantation is that it is possible for the mother to nurse these tiny cubs for two months in her den, whereas if they had been implanted immediately and thus grown throughout pregnancy, they could be 10 pounds or more, and require more milk than the mother could provide
• Cubs are born relatively bald, eyes closed, and helpless

Grizzly Bear Fact Sheet

Scientific Name: Ursus arctos horribilis
Other Names: brown bear, grizzly, silvertip, roachback
Order: Carnivora
Family: Ursidae

The grizzly bear is the largest terrestrial carnivore in the lower 48 states. This predator is distinguished from black bears by a distinctive hump on the shoulders, a dished profile to the face, and long claws about the length of a human finger. Coloration is usually darkish brown but can vary from very light cream to black. The long guard hairs on their back and shoulders often have white tips and give bears a “grizzled” appearance hence the name “grizzly”.

Size and Lifespan:
• In this part of the continent they are 3-3.5 feet tall on all fours and 6-7 feet tall when standing
• Adults may weigh from 325-750 pounds
• They can live to be up to 30 years in the wild, though 20-25 is normal

Diet:
• Although the grizzly is the largest carnivore, it is also the least carnivorous carnivore on this continent
• They eat mostly plant material, to the amount of 26-35 pounds of food a day for the average adult
• Flowering plants, roots, and berries make up the majority of their diet. They are however, opportunistic feeders and will eat ants, ladybugs, ground squirrels, mice, fish, and carrion (carcasses) when available. They are also known to hunt big game elk, moose, deer, etc.

• Adult grizzlies put on 220 pounds of fat in the fall, in preparation for the long hibernation period when they usually do not eat at all.

Behaviors:
• Largely solitary, only meeting to mate, with the exception of a mother with cubs and siblings who sometimes stay together for a year after leaving their mother; two bears may pass each other while grazing and ignore each other but sometimes will hunt in pairs
• Range can be extensive (up to 1000 miles), or may spend lives within 20 miles of birth
• They are not true hibernators, but rather “winter sleepers” with their heart beat slowing down and breathing 4-5 full respirations a minute
• Dig dens 4-8 feet in diameter, 4-6 feet wide to sleep in, usually on a slight slope or under a tree, using roots as a support for den
• Makes a bed with thick carpet of leaves, grasses, bark, twigs, boughs
• They do not excrete wastes during sleep, belly is empty
• Survive on body fat; layer of fat approaches 8 inches in some places
• Enter dens in October and November; emerge between late March and early May
• In some northern areas, grizzlies sleep half of their lives

Mating and Reproduction
• Mating season is between May and June with males seeking out females in estrus, and courting begins. Males follow females for miles and occasionally she allows him to approach her for nips, paws, and grunts. When ready, the female submits and copulation occurs, lasting from a few minutes to an hour, usually 20-30 minutes. Males and females may remain together for duration of estrus period, lasting from a few days to a month, or may separate immediately.
• Although females 3.5 years old will mate, first conception usually takes place at ages 5-6
• Gestation last 210-255 days and like the black bear, delayed implantation allows the cubs (usually 2-3) to be born at a low weight of less than a pound
• Cubs are born blind, relatively bald, eyes closed until 5-6 weeks old, 3-4 inches long,
• Cubs remain with their mother for 1.5- to 4.5 years, usually leaving their mother the spring of their third year

Other Information:
• In 1975,The U.S. Fish and Wildlife Service listed the brown grizzly bear as a threatened species in the Lower 48 states, under the Endangered Species Act, meaning it is considered likely to become endangered
• In the lower 48 states there are 800-1,020 grizzly bears
• In Alaska, where there are an estimated 30,000 grizzly bears, they are classified as a game animal with regionally established regulations
• Most of the threats to the survival of grizzly bears are associated with degradation of habitat due to development, logging, road-building and energy and mineral exploration.

Moose Fact Sheet

Scientific Name: Alces alces
Order: Artiodactyla
Family: Cervidae

Range: Northern regions of North America (Alaska to northeastern U.S.), southward to central; regions of the Rocky Mountains; found in every Canadian province and 16-20 of the original 48 states. Eurasian moose called elk (elch)

Physical Characteristics:
• Largest of the deer (cervidae) family. Average weight is 1,000 lbs. (male); 900 lbs. (female); up to 1800 lbs.
• Second heaviest herbivorous land animal on continent (to bison)
• Largest antlered creature in world; tallest mammal in Americas
• 72-75 inches at shoulder, up to 126 inches long from nose to tail
• Great overhanging shout; long nose ends in large, flexible upper lip
• Pendulous muzzle
• Pendant-like fur covered skin hanging from upper neck: “bell”
• Bulging neck
• Short, inconspicuous tail
• Small rump
• Large, donkey-like ears, not as long as donkey’s
• Coarse, brittle fur
• Color: dark brown to reddish or grayish brown to nearly black; brown-grey or white leg stockings
• Males have massive palmate antlers: extend outwards from sides of head, can be 48 in. across; shed antlers between late fall and early January each year; antlers weigh up to 77 lbs.
• Have extremely poor eyesight, keen sense of smell, very sensitive hearing
• Have exceptionally long legs for walking in deep snow in winter, wading in ponds in summer
• Female is up to 25% smaller than male

Behavior:
• Adults come together only during breeding season; may aggregate in good browsing areas, but barely tolerate each other
• Use rubbing trees in fall to help remove velvet covering antlers
• Good swimmers, take readily to water, can paddle at a steady 6 m.p.h. for long distances, can swim for 15 miles, reportedly are able to submerge for 3-4 minutes
• Water-oriented creatures: thrive in dense forests bordering shallow lakes; most often seen in or near water, largely because of diet
• Vocalizations: soft bawl (calf); grunt, moan to attract bulls during mating, short, harsh bark for threats (cow); roar during breeding to attract cows, grunts, rustling antlers in vegetation, moaning, tongue-flicking during courtship, short, harsh bark for threats (bull).

Diet:
• Browse underwater plants: water lilies and roots of many aquatic plants
• Eat twigs, leaves, bark of deciduous and evergreen trees and plants (willows, bitterbrush, Douglas Fir, cottonwood, subalpine fir, whitebark pine, coneflowers, snakegrass, rushes, blue spruce, fireweed, aspen bark, mountain ash).
• Will eat up to 60lbs of food each day
• Will highline trees in winter (eat bark above snowline)
• Favorite winter food: willow

Mating and Reproduction
• Mating season lasts 4-8 weeks beginning in September
• Bull will come together with one cow, remaining together for about 10 days, then abandons and seeks another
• Violent battles between bulls occur during rut (mating season)
• Gestation period 8 months: 1-3 calves (usually 1), at 25-35 pounds
• Young remain close to cow through first year
• To give birth, cow seeks quiet, secluded spot, i.e. a peninsula or island, and is very quick-tempered when with young
• Calves not spotted, like elk or deer; but are reddish-brown

Predators: Cougar, bear, timber wolf, mountain lion, (all often unsuccessful because of the massive size of a moose)

Mule Deer Fact Sheet

Scientific Name: Odocoileus hemionus
Order: Artiodactyla
Family: Cervidae

Range: Mule Deer occur throughout western North America and Wyoming in habitats ranging from deserts, riparian areas, broken grasslands, shrublands, foothills, forests, to tundra. This is one of the two species of deer in North America (other is White-tailed deer). Both occur in this area, through Mule Deer are more abundant.

Physical Characteristics:
• Males have symmetrically forking (Y-shaped forks) antlers; “dichotomously branched”; shed antlers March-April
• Named for large ears; triangular and set high on head
• Large, round eyes set well to side of head; excellent eyesight
• Graceful, elongated bodies, slender legs and necks, short tails, angular heads
• Average height at shoulder: 40 in (male); 35 in (female)
• Average weight: 220 lbs. (male); 150 lbs (female)
• Coat: rusty red in summer, brownish gray in winter; face and throat are whitish with a black bar round chin and forehead; belly, inside of legs and rump patch are white; tail white with black at tip
• Maximum speed: 25 m.p.h.

Mating and Reproducing
• Reach sexual maturity at 18 months
• Breed mid-November to early December: polygamous; males become aggressive and move around extensively seeking females in estrous
• Buck rutting behavior includes snorting, urine marking, thrashing and rustling antlers in vegetation, sparring and antler fighting
• Birth occurs following June after gestation period of around 203 days
• Twins are common, though can be between one and three fawns, weighing 6-18 lbs.
• Fawns have spotted coats: help in protection from predators
• Life span: 10-12 years

Behaviors:
• Small ranges with short distance to food, water and cover
• Neither solitary nor gregarious; usually small groups or individuals; groups led by adult doe
• Diet: totally vegetarian, primarily browsers: eat plants, shrubs, trees, forbs, grasses, sedges; commonly visit salt and other mineral “licks;” serviceberry, sagebrush, snowberry, pine, sunflower, rose, barberry, bearberry, mountain laurel

Pronghorn Fact Sheet

Scientific Name: Antiilocapra americana
Order: Artiodactyla
Family: Antilocapridae

• Sometimes called antelope, though not the true name
• Name stems from forked horns; only North American ungulate with forked horn
• Endemic to North America
• Habitat consists of high open plains, desert shrub grasslands, and mountain basins
• Range: occur throughout western North America from Canada to northern Mexico

Physical Characteristics
• Size: male-150 lbs.; female – 100 lbs.; 35 in at shoulder
• Black horns with fork, or prong; females have horns, though much smaller than those of males (usually not visible), and generally without forks
• Do not shed antlers, though outer sheath is shed annually
• Color: rusty brown with white stripes across necks, white bellies, large white rumps, black and dark brown markings on head
• Black cheek patch usually visible in adult males, as well as dark markings on neck
• Hair on rump flares when frightened, serving as flags of herd
• Large black eyes with heavy black eyelashes

Mating and Reproduction
• Reach sexual maturity at 18 months
• Breeding season is mid-September through mid-October
• They are polygamous, territorial, and males gather harem
• Gestation lasts 250 days
• Calving season late May to mid-July; number young varies from 1 to 3 (usually 2); young weigh 8-9 lbs.
• Life span: up to 12 years

Other Facts:
• Fastest North American land mammal: maximum speed is 60 m.p.h.
• Inhabit sagebrush plains; where can take advantage of unrivaled speed
• Predators include coyote, bobcat, eagles on fawns
• Vocalizations: Fawn: bleat, wine; Doe: grunt, snort; Buck: loud moan, snort, tongue-flicking for courtship and herding; short, harsh barks for threats
• Diet: shrubby, woody plants (esp. sagebrush) and forbs, rabbitbrush, snowberry, snakegrass, grasses eaten least
• Migrate in winter because not adapted for snow
• Active day and night
• Migrate spring and fall

References

Kelly Campus of Teton Science School Beaver Fact Sheet:

Rue, Lee Leonard, III. 1964. The World of the Beaver. Philadelphia, Pennsylvania: J.B.
Lippincott Co.
Ryden, Hope. 1986. The Beaver. New York: Lyons and Burford Publishers.

Kelly Campus of Teton Science School Bison Fact Sheet:

Caras, Roger A. 1967 North American Mammals. New York: Galahad Books.
Halfpenny, Jarnes. 1986. A Field Guide to Mammal Tracking in North America.
Boulder, Colorado: Johnson Books.
Stelfox, J. Brad, Ph.D., and Lawrence, Lynn. 1991. A Field Guide to The Hoofed
Mammals of Jackson Hole. Salt Lake City, Utah: Lorraine Press.
National Geographic. 1981. Book of Mammals, Vol.I. Washington, D.C.: National
Graphic Society.

Kelly Campus of Teton Science School Black Bear Fact Sheet:

Halfpenny, Jarnes. 1986. A Field Guide to Mammal Tracking in North America.
Boulder, Colorado: Johnson Books.
Macdonald, David, Editor. 1985. Encyclopedia of Mammals. New York: Facts on File,
Inc.
Schullery, Paul. 1986. The Bears of Yellowstone. Boulder: Roberts Rinehart, Inc.
Publisher.
Zoobooks: Bears. San Diego: Wildlife Education, Ltd.

Kelly Campus of Teton Science School Grizzly Bear Fact Sheet:

Mammals in North America, R.E. Wrigley;
Macdonald, David, Editor. 1985. Encyclopedia of Mammals. New York: Facts on File,
Inc.
Field Guide to Mammals of North America., Burt & Grossenheider.
Kid’ Planet: http://www.kidsplanet.org/factsheets/grizzly_bear.html

Kelly Campus of Teton Science Schools Moose Fact Sheet:

Halfpenny, Jarnes. 1986. A Field Guide to Mammal Tracking in North America.
Boulder, Colorado: Johnson Books.
Stelfox, J. Brad, Ph.D., and Lawrence, Lynn. 1991. A Field Guide to The Hoofed
Mammals of Jackson Hole. Salt Lake City, Utah: Lorraine Press.
National Geographic. 1981. Book of Mammals, Vol.I. Washington, D.C.: National
Graphic Society.

Kelly Campus of Teton Science Schools Mule Deer & Pronghorn Fact Sheet:

Clark, Tim W., and Stromberg, Mark R. 1987. Mammals in Wyoming. Lawrence,
Kansas: University Press of Kansas.
Halfpenny, Jarnes. 1986. A Field Guide to Mammal Tracking in North America.
Boulder, Colorado: Johnson Books.
Stelfox, J. Brad, Ph.D., and Lawrence, Lynn. 1991. A Field Guide to The Hoofed
Mammals of Jackson Hole. Salt Lake City, Utah: Lorraine Press.

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