Chapter III: Introduction (2)

The beaver’s winter diet consists of bark from the tree branches that it stores up by sticking them into the mud at the bottom of the pond. In the summer the bark diet is supplemented by the addition of roots and green vegetation.

The four to six young are born in the house or the bank den in May or June where they remain until able to make the underwater swim to the outside where they soon assist their parents in the work of the colony.

The beaver is equipped with a large flat paddle-like tail. However, contrary to stories, he does not use it as a trowel or as a means of transporting mud. It is an excellent rudder and also a prop or brace for the owner while he stands up to cut down a tree. The resounding slap of the tail upon the surface of the pond is an excellent warning signal that immediately puts the colony on guard.

General description: Largest of the North American rodents, stocky, with webbed hind feet and broad, flat, scaly tail, ears short, fur thick, rich dark brown. Total length 43 inches; weight from 30 pounds to a maximum of 68 pounds. Tail 4 or 5 inches wide and 12 to 16 inches long.

Where found: Along almost every stream in Yellowstone. They might be seen in the beaver ponds in Willow Park, or along Pelican Creek; or at the beaver ponds and Floating Island Lake between Mammoth and Tower Fall. Longest dam in the park approximately 1000 feet in length is at Beaver Lake opposite Obsidian Cliff. The best time to see beaver is in the evening. Beaver change their locations frequently and it is difficult to predict, from season to season, where they can best be seen.

OTTER
Lutra canadensis

This large member of the weasel family can outswim some fish. His lithe shape and short powerful legs with broad webbed feet make him an expert and his graceful maneuvers in the water are very interesting to see.

The principal item of the Otter’s diet is fish which are supplemented by frogs or crayfish and such young ducks, muskrats or other small mammals or birds as they may have occasion to catch. Their habitat is therefore near suitable streams, lakes or ponds. They have been known, on some occasions, however, to undertake fairly long overland journeys between streams.

The otter is a rather friendly fellow, fairly easily tamed and observed. They usually travel in pairs or family groups. Otters are playful and are in the habit of making slides down steep clay-banks or snowdrifts where they seem to have great sport coasting down on the chest and belly, ending up in the water with a loud splash. This they do over and over like a group of small children.

The den is located near the water, either as a burrow in a bank or under protecting tree roots or rocks. Here the one to three or four young are born in late April, there being only one family a year.

Otters are strong and capable fighters, a match for a dog on land and more than a match for one in the water. They have no particular enemies except man. The rich brown fur has brought a high price on the fur market and trapping operations have resulted in the animal becoming rare outside of such protected areas as Yellowstone. The rather short dense pelt is considered to be one of the most durable of furs and it, together with the layer of fat underlying the skin, make the otter impervious to the icy water in which he spends much of his time.

General description: A long, lithe-bodied animal with webbed feet and a long, tapering, muscular tail. Size large, head broad and flat, legs short. Color of upperparts a uniform, dark, rich, glossy-brown; underparts lighter with a grayish tinge. Total length 40-45 inches, tail 12½ to 15 inches; and weight 18 to 25 pounds.

Terms: Sexes—Male and Female; young—pups or kittens.

Where found: They are active all of the year and are found on many streams and lakes throughout the park. Best seen near the outlet of Lewis Lake and near the boat docks at Lake and West Thumb. Active at all hours.

WESTERN MINK
Mustela vison energumenos

The mink is a large weasel of slightly heavier build and semi-aquatic in habit. Found widely distributed in forests or on plains but always along watercourses where it establishes its den. This may be a burrow in the bank, under logs or rocks and similar places.

They are strong and graceful swimmers and are fully capable of catching trout and other fish which form a part of their diet, as well as frogs and crayfish. They also hunt on shore for muskrats, mice, rabbits, snakes, birds and similar forms of small animal life. The mink is sometimes of bloodthirsty temperament, killing for the pleasure, but is not ordinarily considered quite as much inclined this way as the smaller weasels.

The odor of the musk carried by the mink as well as the other weasels is strong and very offensive. This is released in moments of excitement.

The mink has but one litter of young a year, numbering five or six in the average litter, which are born in April or May.

General description: A slender weasel-like animal nearly as large as a house cat. Ears small, neck long, tail moderately bushy. The fur is soft and dense, protected by long guard hairs, rich, glossy dark sooty brown in color with a white area under the chin. Total length 24 inches, tail 8 inches; weight up to 2 pounds, the females somewhat smaller.

Where found: Along some of the streams and ponds of the park but not very common and seldom seen.

ROCKY MOUNTAIN PINE MARTEN
Martes caurina origenes

This little animal is close kin to the famous Russian Sable and has a valuable pelt or rich, dense fur. Expert climbers, they hunt through the woods and capture a good portion of their menu from the tree tops. Largely carnivorous the marten lives on small mammals and birds. Its main foods in Yellowstone are squirrels, chipmunks, mice, rabbits, grouse, and also some nuts, berries, fruits, insects or honey.

Fearless and pugnacious they frequently quarrel among themselves and do not hesitate to snarl or spit at man. One time a ranger was standing in front of a patrol cabin when a marten came bounding toward him spitting and snarling at every jump. To see what he would do the ranger made for the cabin door and the marten came right after him even to the cabin door. It was decided that they would be pretty tough to live with if they suddenly became as big as bears with an increase in disposition accordingly. A marten family quarrel sounds like a good cross section of an alley-cat serenade. Being extremely active they are able to elude most would-be enemies except possibly the Great Horned Owl.

The marten nest is usually in a hollow tree or rarely in a burrow, where the young, averaging 3 or 4 to a litter, are born late in April. It is said that the young are blind for about the four weeks after birth.

General description: A small animal, of weasel-like form, a little smaller and more slender than a house cat; head rather small with ears broad and rounded, tail bushy and cylindrical, about half as long as the head and body. Fur soft, rich yellowish brown; legs, feet and tail dark brown; buffy patches on throat and chest. Total length 25 to 28 inches, weight 1½ to 4 pounds. Males largest.

Where found: Fairly common throughout wooded sections of the park but are shy and seldom seen, especially near habitations except isolated cabins where they sometimes become rather tame.

PORCUPINE
Erethizon epixanthum

The Yellow-haired Porcupine of Yellowstone occurs all over the park. Being an unsociable sort of fellow he is usually found alone, except during the mating season or when the young are yet with their mother. He is a common animal but seldom seen.

He is a heavy set, slow, clumsy animal with short legs and a waddling walk. Very stupid and short-sighted with a habit of complaining audibly to himself as he goes along. Since the porcupine is well protected by a back full of loosely fastened quills, he is very unpopular with the other animals, especially those that might have an idea of making a meal of him.

The quills are his only battle equipment but are sufficient protection against most animals. Each individual quill is equipped with sharp barbs at the tip which easily penetrate flesh, gradually working their way deeper and are very hard to extract. Porky, however, does not have the power to throw his quills, in spite of stories to the contrary. When attacked he bristles up and looks like an animated pincushion and a slap from his quill-loaded tail is sufficient to fill the face and mouth of his would be attacker with a painful collection of quills which he will long remember.

The porcupine’s nose is very sensitive, a good blow on it being sufficient to kill him, so he has learned to tuck it down between his feet for protection, and to turn so that his back and tail are presented to the enemy. There are no quills on his underside and an occasional enemy has learned to reach under with a paw and quickly flip him over on his back in order to expose the unprotected portion for final attack.

The principal food of the porcupine, in winter, is the bark and small twigs of various trees. In the summer, the bark, buds and foliage of many trees, shrubs and plants are used. Porky is very fond of salt and will gnaw on anything that contains it; shovel or other tool handles with deposits of perspiration on them, or antlers after being shed, are a delicacy. Occasionally he kills a tree by removing too much bark but seldom does enough damage to be of economic importance.

One litter with usually one, or rarely if ever two young, is born each year in late April or May. A baby porcupine at birth weighs about a pound and is as large or larger than a bear cub. The den is located among rocks, in cavities under logs or fallen tree tops. However, during most of the year, even in the winter, the favorite place is well up in the tops of the trees.

General description: A large, clumsy rodent with fairly soft hair with which is mixed longer, coarser hair and many stiff, sharp, barbed spines or quills over the upper parts and tail. Tail short, thick and muscular. In color black with longer hairs tipped with greenish-yellow. Total length 32 inches, weight 15 to a maximum of 35 to 40 pounds.

Where found: In all timbered areas of the park and is sometimes seen near the roadsides or trails either during the day or night.

BADGER
Taxidea taxus

Many of the smaller animals, especially those of the rodent group, are known for the dens and runways that they dig, some of them becoming rather expert at this activity. Their burrowing activities, however, are undertaken primarily as a means of providing a suitable home for the animal. The Badger, however, is equipped by nature as an excavating machine. He, too, makes a burrow for use as a home but this is only a small part of his digging activities.

Badgers are equipped with large strong claws, especially on the forefeet, and backed by powerful muscles they can literally dig themselves out of sight in a surprisingly short time, throwing out a stream of dirt behind them like a mechanical elevator. It is this ability that he depends upon as a means of securing his food. Badgers are rather clumsy, heavy bodied and short legged animals, lacking the speed and dexterity needed to capture their prey in the open, but how they do like to dig for their food! Living primarily on the smaller rodents, especially ground squirrels, the badger snoops from burrow to burrow until his nose tells him that the occupant is at home, then dirt starts to fly. If the ground squirrel has provided his home with some extra entrances and he is quick to use one of them he may escape, otherwise the badger has secured a dinner.

Entirely beneficial from the standpoint of the kind of food he eats, the badger’s activities in obtaining it soon result in numerous holes throughout the area where his foraging operations are carried on. In areas where domestic stock are ranging these excavations made by the badgers are hazards to the stock and rancher alike, often resulting in a broken leg to the horse that steps into a hole and sometimes serious injury to the rider when he is thrown from the horse as it falls. In such areas this animal is usually hunted or trapped by man. In Yellowstone he is left to live an undisturbed life. The badger is a fearless and vicious little fighter, which combined with his digging ability makes him a match for anything but man and his gun.

Badgers inhabit the plains and prairies or open forests, wherever their principal food items of ground squirrel, gopher or prairie-dog can be obtained. They generally hibernate from October to March, except in the southern portions of their range. The young, probably averaging about three to a litter, are born in May or early June.

General description: A low, heavy bodied animal with short legs, short bushy tail and long shaggy fur. Color a silvery gray grizzled with black. Head rather small, broad and flat with black and white striped markings. Total length 28 inches and weight averaging about 14 pounds.

Where found: Northern part of the Park from Mammoth to Tower Junction and the Lamar Valley, in open sections. Occasionally seen in meadows of the interior parts of the park where the picket-pins are to be found. Badgers are not numerous, but could be called commonly seen residents, especially of the northern side of the park.

SAGEBRUSH WHITE-FOOTED MOUSE
Peromyscus maniculatus artemisiae

The White-footed Mouse, Deer Mouse, or Vesper Mouse is an interesting little animal, a member of a very large and widely distributed genus whose members are generally the most common small animal of any given region. They are clean little creatures with large bright eyes, large ears, and tails about as long as their bodies, with gray or brown upperparts and white feet and lower parts.

These mice are found throughout the forests, among rocks, in meadows and open grassy places, living in burrows, among rocks, or in hollow trees and logs and they frequently come into camps and houses. They are expert climbers and will readily take refuge in trees as well as into burrows if the occasion warrants.

White-footed mice depend upon seeds and grains, small nuts and dry vegetable matter for their food rather than green vegetation like the meadow mice, and are rarely carnivorous.

They may have three or four litters of 3 to 7 young each year and so are able to keep pace with the activities of their enemies which include all of the smaller carnivorous animals and the owls.

General description: Upper parts, pale cinnamon to brownish fawn, more dusky along mid-back; underparts and feet white. Total length 6 to 7½ inches with the tail being one-third to one-half of the total length.

Where found: It is possible to find them almost anywhere in the park but since they are nocturnal they are rarely seen in the daytime.

MEADOW MOUSE OR VOLE
Microtus sp.

The Meadow Mouse is one of the more common and widely distributed of our small mammals. There are many species and subspecies and some form is to be found practically anywhere in North America.

These little mice prefer the open meadow country where there is plenty of grass the entire year. They may be found in the moist to semi-arid sections and anywhere from sea level to above timberline elevations.

Their presence can be readily detected by the characteristic runways through the grass. The mouse makes the runway both by cutting some of the grass and pushing the balance to the side, and the floor of the runway is kept free from all obstructions. A colony of mice will have a regular labyrinth of these paths with frequent openings into underground burrows and nests. The young are usually born in the underground nests. However, many of the species also build surface nests of thick balls of grass which are used during the winter time. In these nests, when snow blankets the landscape they are warm and secure, and able to run about their passage-ways, beneath the snow in their daily quest for food, for they do not hibernate.

The food of the meadow mouse is chiefly vegetation: grass, foliage, seeds, twigs, roots and bark and at times they may become very destructive to field crops and orchards.

This little animal is very prolific and usually has several litters each year, with each litter consisting of from four to eight young. Were it not for their many enemies they would soon overrun the grass lands and do untold damage. As it is, their enemies, which are practically every predatory animal and bird, can barely keep them in check. Meadow mice serve as a valuable source of food for the smaller predatory animals such as coyotes, foxes and for the various hawks and owls.

There are four species of these mice that have been found in Yellowstone Park:

Sawatch Meadow Mouse: Microtus pennsylvanicus modestus. A medium-sized
mouse with upperparts dull ochraceous, sprinkled with black.
Underparts soiled whitish to ashy or cinnamon. In winter many
black hairs along upperparts and underparts with wash of creamy
white. Total length 7 inches, tail 1.8 inches. Has been found at
Mammoth Hot Springs, Upper and Lower Geyser Basins and Shoshone
Lake.

Dwarf Meadow Mouse: Microtus montanus nanus. A small-sized, rather
short-tailed mouse with upperparts everywhere mixed gray, sepia
and blackish, feet grayish; tail bicolor, dusky gray and whitish;
underparts whitish. Total length 6 inches; tail 1.6 inches. Found
in the grass of meadows and upland slopes over most of the park
and appear to be the most abundant and generally distributed of
the meadow mice in the park.

Cantankerous Meadow Mouse: Microtus longicaudus mordax. Resembles
Sawatch meadow mouse in size but the tail is longer, ears larger,
and color grayer. Upperparts grayish bister; sides grayer,
underparts whitish. Lighter colored in the winter. Total length
7.4 inches; tail 2.8 inches. These mice have been found at Mammoth
and Tower Fall and are probably common in most of the meadows of
the park, equally at home on dry ground or in mountain streams.

Big-footed Meadow Mouse: Microtus richardsoni macropus. Largest of the
meadow mice. Total length 8.8 inches; tail 2.8 inches. Upperparts
dark sepia mixed with black, sides paler, feet gray; tail bicolor
sooty whitish; underparts washed with silvery-white. In winter
grayer above, more white below. Usually found close to water where
they swim much in the manner of muskrats. This mouse had been
taken at Heart Lake and its runways seen in marshy meadows of most
of the western part of the park.

WOOD RAT
Gray Bushytail Wood Rat—Neotoma cinerea
Colorado Bushytail Wood Rat—Neotoma cinerea orolestes

Pack Rat or Trade Rat is the name commonly applied to this individual, represented in the park by both of the above forms. Pest of the stations and patrol cabins because of his fondness of getting into buildings and collecting items of every description, especially those of shiny appearance. These are packed to his nest, which is located either in rock piles, cliffs or whenever possible in or around buildings. He cuts open food containers, bedding and other contents and makes a general mess.

He frequently leaves some object in place of the stolen article, hence the name trade rat. However, this trade is probably due to his dropping something that he was already carrying, when he spied the new object that was more attractive, rather than any desire to make a fair trade. They gather anything that is of a convenient size to carry.

The wood rat is a very clean animal, of no relation to the common barn rat except in superficial resemblance. A vegetarian in diet he lives on green vegetation such as grass and foliage, fruit, bark, roots, fungi, seeds and nuts. He is active all year but seldom accumulates much of a store of winter food.

Mainly nocturnal in habit, they are, however, occasionally seen in the daytime. Their principal enemies here are hawks, owls, weasels, coyotes and martens.

The young, from three to six in a litter, are born in June or July and are duller in color than the parents.

General description: Large in size, mouse-like in appearance. The fur is fairly long, soft and grayish buff in color, darker in the Colorado form, on the upperparts, white underparts and feet, and a large, bushy, flattened almost squirrel-like tail. Total length 15 to 16 inches. Sexes equal in size.

Where found: Throughout the park. The gray wood rat mainly in the transition zone in open country along the Yellowstone, Lamar and Gardner Rivers and around Mammoth. Colorado wood rat in higher portions of the park.

ROCKY MOUNTAIN MUSKRAT
Ondatra zibethica osoyoosensis

Quiet streams or the shallow grassy margins of ponds and lakes are the home of this valuable little fur-bearing animal. More valuable than many people realize since few know that he is the Hudson Seal and other trade names of our popular fur coats. Ironically, muskrat fur is used as an excellent imitation of his greatest enemy, the mink, in the mink-dyed muskrat coats.

A hardy little animal that lives much like the beaver, in bank dens with underwater entrances or in dome-shaped houses made of rushes, grass, turf and mud instead of the coarser sticks and branches used by the beaver. In these houses or bank dens they spend the winter in comfort. Remaining active all of the year and seldom storing any food, muskrats are out in the coldest weather.

Their food consists of bulbs and tubers, roots, tender portions of numerous marsh and water plants, sedges, grass and clover, and possibly some small aquatic animal life, salamanders, etc. In the winter it is sometimes necessary to make extensive excursions under the ice in search of food.

The young are born in the house or bank nests in May or June, usually six or eight in a litter. In lower, milder sections more than one litter is raised during the year. Fortunately muskrats are prolific breeders.

The name muskrat originated from the fact that there are two glands near the base of the tail that contain the strong though not unpleasant musk, which may be left at intervals about his haunts possibly as signs or marks of possession. While several may use the winter house the muskrat is ordinarily rather fussy and gets into frequent fights over territorial rights.

General description: A rather large, robust, somewhat rat-like appearing animal, with short legs and broad feet, the hind ones partially webbed; tail long, scaly and sparsely haired, flattened laterally. Ears scarcely showing above fur which is dense with longer guard hairs. Upperparts are dark brown, underparts lighter in appearance. Total length 23½ inches, tail 10 inches; weight about two pounds.

Where found: Throughout the park along moving streams, like the Yellowstone River between Lake and Canyon, and most of the ponds and lakes. Frequently working in the morning and latter part of the afternoon as well as at night.

PIKA
Ochotona princeps ventorum

This little Pika, Cony or Rock Rabbit of Yellowstone is in reality a diminutive, tailless rabbit. Common in the higher elevations wherever loose rock piles and slides offer suitable locations for his home.

Timid and secretive in nature and possessing a protective coloration that makes them hard to locate in their rocky homes, the pikas are not often noticed by the majority of park visitors. The call of a pika, a squeaky bleat, has an elusive quality that confuses the hearer as to the direction in which it originated.

The best indications of the habitation of the pika are the small stacks of hay among the rocks. He is an industrious little farmer and is usually busy during the summer cutting and curing grass and plant foliage for winter use. This material is first put in the sun to cure, then piled in sheltered places among the rocks where it will be accessible during the winter when the snow has made a protective blanket over the landscape. In protected cavities and runways beneath the rocks, with an ample supply of hay, the pika has nothing to worry about during the winter months and find no need to hibernate. Just what family activities they have during this period is not known.

If an observer remains quiet near their rocky homes he may soon be rewarded by a sight of them running silently about over the rocks, and it may occasionally be possible to approach close enough for a picture.

The young, from three to five in number, are born from late May or early June to early September. Due to their secretive nature and the location of their homes not a great deal is known yet about the home life of the pika.

General description: A short, chunky, apparently tailless rabbit-like animal, ears rounded and of good size; legs short and hind legs very little longer than forelegs. Color of upperparts grayish to buffy, underparts whitish varying to cinnamon-buff. Sexes alike in color and size; about 7½ inches long, height to shoulder 3½ inches and weight 4 to 7 ounces.

Where found: Distributed throughout much of the park at elevations above 7,000 feet wherever rock slides and talus slopes are available. Most likely seen around the Golden Gate, Sheepeater Cliffs, cliffs south and west of the Upper Geyser Basin, rockslides along the Dunraven Pass road and other such places. Look for the hay piles as indications. Active during the daytime.

BLACK HILLS COTTONTAIL
Sylvilagus nuttalli grangeri

This shy and timid little rabbit leads a precarious existence in the sagebrush-covered valleys of the lower portions of the park. Its numerous enemies, especially the coyotes, foxes, bobcats, hawks and owls keep the cottontail constantly on the alert and seldom far from dense thickets or sheltering rocks. Its short legs are not a match for the speedy coyote and so artful dodging and hiding tactics must be resorted to.

The mother cottontail makes a nest, lined with her own fur, in a sheltered place where the young, born blind, naked and helpless, are placed. They grow rapidly and are soon able to run about and play, then it isn’t long until they are out on their own. There are usually several litters born each year; this helps keep up their numbers in spite of the inroads made by the various enemies.

General description: A small rabbit with short ears and legs. Upperparts of creamy-buff color lightly grizzled with gray. Tail short and fluffy, gray on top and white on underside. Total length 15 to 16 inches.

Where found: Most likely to be seen near Mammoth and in sagebrush flats along the Gardner River. Mainly found in the transition zone and lower. Most frequently out in the early morning, evening or during the night.

ROCKY MOUNTAIN SNOWSHOE RABBIT
Lepus americanus bairdi

The Varying Hare or Snowshoe Rabbit is found throughout the higher parts of the mountains, fairly common but not abundant in numbers. Provided by nature with special adaptations, this rabbit is not bothered greatly by the winter storms and snow. Very large furry hind feet act as snowshoes enabling these rabbits to scamper readily over the snow without sinking in and thus are the basis for its common name.

Nature also provides these hares with a camouflage to help protect them from their enemies. Their summer coat of fur is dull brown in color which blends well with the forest floor, while in the winter they get a new coat of pure white, except for black ear tips, making them hardly distinguishable from the snow drifts over which they run. This varying color with the seasons is the source for the other name by which it is known.

These rabbits, like other members of the family, depend upon the foliage of plants and shrubbery as their principal food; however, when this is buried beneath the winter’s snow their diet is frequently mainly composed of the bark of bushes and small trees.

The snowshoe rabbit makes a nest in a sheltered place, where the young, usually three or four in number, are born. These young, unlike the cottontail, have their eyes open and are covered with a coat of very fine close hair. They leave the nest in about ten days. In some places there may be more than one litter in a year.

General description: Larger than a cottontail with long ears and hind legs. Color of upperparts (summer) buffy grayish brown to rusty brown, underparts and bottoms of feet white; (winter) white, with black-bordered tips of the ears and underparts pale salmon. Total length about 18½ inches.

Where found: Likely to be seen almost anywhere in the wooded sections of the park and near the camp and cabin areas. Especially during the early morning and evening. They are generally rather tame.

WHITETAIL JACKRABBIT
Lepus townsendi campanius

This big Prairie Hare is readily distinguishable from the other jackrabbits by its all white tail. It may also be found at higher elevations than the other species of jacks. Normally frequenting the open country it has been seen in alpine meadows above timberline at 10,000 feet elevations. This species is the largest of the jackrabbits.

All of the jackrabbits are known for their speed as they go bounding over the prairie, covering twelve to fifteen feet at a jump. The whitetail is the fastest and best jumper of the lot. When in high-gear speed he is a match for all but the fleetest of greyhounds.

The whitetail jackrabbit makes little if any nest for the young, but like other rabbits, does have several forms scattered about his home range. The form is simply a place just large enough to accommodate his body, padded down and hollowed in a clump of grass, weeds or bushes. Each individual has several of these forms and when not out feeding or playing may usually be found crouched down in one or the other of them. The young are fully furred and have their eyes open when born. They are active but stay hidden close by one spot for the first two or three weeks. There are usually about four to the litter and there probably is more than one litter each year, at least in the warmer sections of their range.

The representatives of this species that live in the northern, colder parts of the country change into a winter coat of white fur each fall and like the snowshoe rabbit are protectively colored when out in the snow. Their large feet also aid them in traveling over the snowdrifts.

General description: A large, heavy bodied rabbit with large ears, long legs, and a good sized fluffy tail that is all white throughout the year. The color above is fairly uniform buffy gray, underparts white. Its winter coat is much the same as the summer, though paler in tone, except in the northern parts of the range, which includes Yellowstone, where it becomes pure white with black tipped ears and irregular buffy patches about the face. Total length 24 inches.

Where found: Open sections in the northern parts of the park. Has been seen on the highest slopes of Mount Washburn. Most frequently seen in the early morning and evening. Not numerous.

ADDITIONAL ANIMALS

The following animals are also found in the park area:

Bangs Flying Squirrel: Glaucomys sabrinus bangsi. A medium-sized
squirrel, total length about 12.5 inches. Upperparts dark grayish
cinnamon; underparts pinkish cinnamon.

These squirrels are strictly nocturnal and for this reason it is
difficult to tell how common they really are. Found only in the
forested areas they nest in woodpecker holes or in hollows in the
trees or possibly build a nest among branches or utilize old pine
squirrel nests when hollows are not available.

Probably common throughout most of the forests of the park.

Mountain Weasel: Mustela frenata arizonensis. A medium-sized weasel
about 14 to 15.4 inches long. Upperparts raw umber-brown, darker
on the head; underparts yellow to orange with a white chin. In
winter the animal is all white with a black tip on the tail.

Frequenting the more open ground in the park they live primarily
on rodents. In the winter they hunt beneath the snow. I have seen
them stick their heads up through the snow, look around and
quickly dive beneath again.

Dwarf Weasel: Mustela streatori leptus. A very small weasel with a total
length of not over 9.8 inches. Upperparts dark brown; underparts
white. In winter it is white with black tip on the tail.

Seldom seen but is probably found in most of the open sections of
the park as it is common on all sides.

Weasels are strictly terrestrial and are very highly carnivorous
and blood thirsty. Very active and courageous attacking without
hesitation animals considerably larger than themselves. They have
very slender, long bodies and short legs.

Northern Plains Skunk: Mephitis mephitis hudsonica. A large skunk with a
large bushy tail. Black in color with a broad white stripe along
each side of the back extending from nape of neck to base of tail.

Reported as common in the lower northern valleys along the
Gardner, Yellowstone and Lamar Rivers and occasional in other
inland valleys by Bailey in 1923.

Longtail Red Fox: Vulpes fulva macrourus. This species has a longer tail
than the average red fox. In color it is a reddish yellow to
golden yellow with grizzled whitish; underparts white; feet and
lower part of legs black.

The red fox although not common is occasionally seen in the north
and northeastern sections of the park. It was at first regarded as
rare but seems to be increasing somewhat in recent years.

Mountain Bobcat: Lynx rufus uinta.

Canada Lynx: Lynx canadensis. These two animals are very similar in
habits though the lynx is more a dweller in the colder forest
regions while the bobcat may be found in more open areas closer to
habitation. Both have tufted ears and a short tail and neither of
the above species has the distinct spots that are characteristic
of some of the species of bobcats. The lynx is the largest of the
bobcats and is slightly larger than the mountain bobcat. The
bobcat has a tail seven or eight inches long with two black bands
on the upper surface in front of a black tip while the lynx has a
tail only about four inches long and with black only on the tip.

These animals are rare in the park area and have only been
recorded in the northern section. My only observation of one was
about eight miles north of the park along the Yellowstone River.

Wolverine: Gulo luscus. Heavily built animals with short legs, short
ears, a short bushy tail, and long coarse hair. Appearing much
like a small, short-legged bear. Total length is from 37 to 41
inches and weight from 22 to 35 pounds. It is dark brown or
blackish in color with two broad, pale, lateral bands of brownish
white to yellowish white from shoulder to rump.

The wolverine is a powerful and savage fighter, strictly
carnivorous and well earns its name of “glutton.” It had a bad
reputation among trappers for it followed their trap lines, robbed
and even broke up their traps and dug up their food caches.
Wolverines are no longer common in this part of the country and
while there may have been a number of them in the park area some
years ago they are probably only very rare visitors now.

Brown Pocket Gopher: Thomomys talpoides fuscus. The piles of dirt which
suddenly appear in the grass of lawns or meadows are made by the
pocket gopher. He excavates a network of tunnels below the sod
line, pushing the dirt through an opening on to the surface, then
filling the opening up again. Their food consists of vegetable
matter such as roots, bulbs, tubers and surface foliage and green
vegetation.

The pocket gopher is rather small in size, about eight inches
long, including a tail of a little over two inches, and is light
brown in color. The tail is only sparsely haired and the front
feet are large and built for digging. The Uinta ground squirrel or
picket-pin is frequently referred to by some people as a gopher,
but it should not be confused with the true gopher and is seldom
seen above the ground.

Found in meadows and open areas throughout the park.

Rocky Mountain Jumping Mouse: Zapus princeps. Sometimes called Kangaroo
Mouse this little animal is a medium-sized mouse with greatly
elongated hind legs and a slender tail nearly six inches long. Its
upperparts are yellowish brown lightly sprinkled with blackish,
the underparts white.

This mouse lives on vegetation and seeds. It is found throughout
the park in meadows and open country but nowhere abundantly. It
hibernates during the winter.

Gale Redback Mouse: Clethrionomys gapperi galei. These mice live on
green vegetation, seeds, roots and stems and probably occupy most
of the forested sections of the park. They live in burrows and are
not very often seen. Several have been trapped in residences in
Mammoth. They are active all winter under the snow.

They are small to medium sized mice with the upperparts reddish
chestnut distinctly differing from the buffy gray sides;
underparts whitish to yellowish gray.

Dusky Shrew: Sorex obscurus.

Mountain Water Shrew: Sorex palustris navigator. Most species of shrews
are smaller than any mice, with pointed noses, minute eyes, and
small ears which are hidden in the fur. They are insect eaters and
like any kind of fresh meat. They are active all winter.

The dusky shrew is a sepia brown in color and is found throughout
most of the park area. Mountain water shrews make their homes in
banks of icy streams and are mouse-size with upper parts slaty
mixed with hoary. They have larger feet than the dusky shrew and
have bristly fringes along the toes with partial webs which equip
them for swimming readily.

The Rocky Mountain Shrew (Sorex vagrans monticola) has been
collected once in the park and it is also probable that the Masked
Shrew (Sorex cinereus) is also here as it has been found in the
surrounding area.

According to Bailey, Yeager and others the following bats have been found in the park during the summer, all migrating south for the winter:

Big Brown Bat: Eptesicus fuscus
Numerous over the central plateau section.
Hoary Bat: Lasiurus cinereus
A few range over most of the park.
Long-eared Bat: Myotis evotis
Numerous in the lower portions of the park.
Silver-haired Bat: Lasionycteris noctivagans
Fairly numerous in timbered areas.
Yellowstone Bat: Myotis lucifugus carissima
Numerous over most of the park and especially at Lake and around the
Devils Kitchen at Mammoth.

BIBLIOGRAPHY

Animal Life in Yellowstone National Park—Vernon Bailey
Yellowstone Information Manual—Fauna—Compiled by Dorr Yeager
Lives of Game Animals—E. T. Seton
Field Book of North American Mammals—H. E. Anthony
Meeting the Mammals—Victor H. Cahalane
A Field Guide to the Mammals—W. H. Burt and R. P. Grossenheider
How to Know the Mammals—E. S. Booth

INDEX

A
Alces americana shirasi, 9
Antelope, 2, 3
Antilocapra americana, 3

B
Badger, 28, 30, 46, 48, 49
Bat
Brown, 66
Hoary, 66
Long-eared, 66
Silver-haired, 66
Yellowstone, 66
Bear, 1, 14, 15, 16, 17, 28, 30, 44
Black, 14, 15, 16, 17, 19
Brown, 15
Cinnamon, 15
Grizzly, 17, 18, 19
Beaver, 5, 37, 38, 39, 40, 54
Bighorn, 3, 12, 13
Bison (Buffalo), 2, 5, 6
Bison bison, 5
Bobcat, 5, 22, 57, 64
Buffalo (see Bison)