In many places the soft, moist earth in the woods is riddled with little pits dug by these squirrels apparently when they are after larvæ or perhaps edible roots. Throughout the summer, but especially during the last half of the season, and in autumn Douglas squirrels work with persistent energy to amass great stores of seed-bearing cones, which they heap, sometimes bushels of them, about the bases of trees, stumps, and the upturned roots of fallen trees or under other shelter. Cones are also buried here and there in the loose leaves and humus. In winter many holes in the snow with piles of cone scales at the entrances show where the owners have dug down to their stores.

Some of their nests are constructed in hollow trees, many others on branches near their junction with the trunks, and still others in underground dens under roots, logs, or stumps. In winter when alarmed these squirrels sometimes race down the tree trunks and take refuge in holes leading through the snow to their food caches and underground burrows. The nests built in tree-tops are usually rather bulky, measuring a foot or more in diameter, and are made of small twigs, dry leaves, moss, grass, and fibrous bark. They are commonly lined with such soft material as feathers and fur. The young, numbering three to seven at a litter, are born at any time between April and October.

The extraordinary intelligence and sense of prevision possessed by squirrels of this group is well illustrated by certain local food migrations. These have been observed in eastern Oregon in years when the cone crop has failed and nothing was available to lay up for winter. Under such conditions to remain in the mountain forests would mean death by starvation before winter had fairly begun. In 1910 and 1913 failure of the cone crop occurred in eastern Oregon and these squirrels promptly left the mountain forests in September and descended along creek courses to the open sagebrush plains as much as seven or more miles from the border of their ordinary haunts. In this open country they wintered successfully, raiding the farmers’ grain bins, root cellars, and other stores, and otherwise showing their supreme fitness to survive in the struggle for existence. With the coming again of summer they promptly returned to their abandoned homes in the pines. It appears to be one of the marvels of animal intelligence that under such circumstances as those named above the entire body of the squirrels on the mountains should have known what to do, especially as a great percentage of their number could never have had any previous experience as a guide.

THE GRAY SQUIRREL (Sciurus carolinensis and its relatives)

(For illustration, see page 547)

The gray squirrel is so well known to everyone in the Eastern States that it scarcely needs an introduction. Many who have not seen it in its native haunts are familiar with it as a graceful and charming resident of parks in many cities. It is about twice as large as the red squirrel and intermediate in size between that species and the fox squirrel. Although sharing some of the range of both the species named, the color of the gray squirrel at once distinguishes it.

The gray squirrel is a North American species with no near relative in the Old World; on the Pacific coast, in the mountains of the Southwest, and in Mexico are other squirrels having much the same gray-colored body, but with no close relationship to it. Its range covers the deciduous forests of the Eastern States and southern Canada from Nova Scotia to Florida, and westward to the border of the treeless Great Plains. Wherever they occur these squirrels are an attractive element in the woodland life, their barking and chattering, their graceful forms, and their activity adding greatly to the cheerful animation of the forest. They are far less vociferous than red squirrels, but their notes are varied and serve to express a variety of meanings.

During the early settlement of the country west of the States bordering the coast, gray squirrels existed in great numbers and often made ruinous inroads on the pioneer corn and wheat fields. In 1749 they invaded Pennsylvania in such hosts that a bounty of three pence each was put on their scalps. Eight thousand pounds sterling was paid on this account, which involved the killing of 640,000 squirrels. In 1808 a law in force in Ohio required that each free white male deliver 100 squirrel scalps a year or pay $3 in cash. Records of the ravages of these squirrels in corn fields are extant also from Kentucky, Missouri, and other States.

Enormous migrations of gray squirrels from one part of the country to another occurred in those days, caused apparently by the failure of food supplies in the deserted areas. Some impulse to move in one general direction at the same time appeared to affect the squirrels and they swarmed across country in amazing numbers, carrying devastation to any farms crossed on the way. When engaged in such movements they appeared indifferent to obstacles and without hesitation swam lakes and streams even as large as the Hudson and the Ohio. Amusing legends grew up concerning these migrations, one of which avers that when the squirrels arrived on a river bank each dragged a large chip or piece of bark into the water and mounting it raised its bushy tail in the breeze and was wafted safely to the other shore! As a fact, many were drowned in crossing large streams and others arrived exhausted from their exertions.

The gray and fox squirrels were favorite targets for pioneer marksmen. The early chronicles tell of the ability of Daniel Boone and other riflemen to “bark” a squirrel, which meant so to cut the bark of the branch on which the squirrel sat as to bring it to the ground stunned without hitting the animal. With the clearing away of the forests, the general occupation of the country, and the decrease of larger animals, gray squirrels have been deprived of most of their haunts and have become such desirable game that they have decreased to a point requiring stringent legal protection to save them from extermination.

Gray squirrels are more thoroughly arboreal than red squirrels and make their nests either in hollow trunks or build them in the tops of trees. These outside nests are common and much like a crow’s nest in appearance except that they are generally more bulky and show more dead leaves. They are built on a foundation of small sticks with a rounded top of leaves, and are lined with shreds of bark, moss, and similar soft material. In the extreme northern part of their range they live mainly in hollow trees, but farther south many winter in outside nests. During severe cold and in stormy weather they remain hidden, sometimes for days at a time.

They have two litters of four to six young a year, the first usually being born in March or April. The old squirrel is a devoted mother and if the nest is disturbed she will at once carry the young to some safer retreat.

In many parts of their range black, or melanistic, individuals are born in litters otherwise of the ordinary gray color. In some districts the number of the black squirrels equals or exceeds the gray ones.

Gray squirrels range through such a variety of climatic conditions that their food varies greatly. They eat practically all available nuts, including acorns, chestnuts, beechnuts, hickory-nuts, and pecans, besides numberless seeds, many small fruits, and mushrooms. They raid fields for corn and wheat, and steal apples, pears, and quinces from orchards to eat the seeds. Like most other small rodents, they are fond of larvæ and insects and also destroy many birds’ eggs and young birds. They are far less serious offenders, however, in destroying birds than the red squirrel.

On the approach of winter they lay up stores of seeds and nuts in holes in trees and in little hiding places on the ground. Many nuts are hidden away singly. In the public parks of Washington, where many gray squirrels exist, I have repeatedly seen them dig a little pit two or three inches deep, then push a nut well down it cover it with earth, which they press firmly in place with the front feet, and then pull loose grass over the spot. One squirrel will have many such hidden nuts, and with nothing to mark the location it appears impossible that they could be recovered. That the squirrels knew what they were doing I have had repeated evidence in winter, even with several inches of snow on the ground, when they have been seen sniffing along the top of the snow, suddenly stop, dig down and unearth a nut with a precision that demonstrates the marvelous delicacy of their sense of smell. Although mainly diurnal, they are sometimes abroad on moonlight nights, especially when gathering stores of food for winter.

Wherever they are, these squirrels are extremely graceful, moving along the ground by curving bounds, the long fluffy tail undulating as they go, or running through the tree-tops, leaping from branch to branch with an ease and certainty beautiful to see. When pressed they make amazing leaps from tree to tree or even from a high tree-top to the ground without injury. They are extremely cunning at concealing themselves by lying flat on top of branches or by gliding around tree trunks, keeping them interposed between themselves and the pursuer.

Gray squirrels are so responsive to protection that they may continue to grace our remaining forests if we properly guard them. In addition to their beauty, they are interesting game animals which should continue to afford a moderate amount of sport—sufficient to prevent them from becoming overabundant and destructive. Now introduced in many city parks throughout the United States and in parts of England, including London, their ready acceptance of people as friends renders them charming animals in such places; but natural food is so scarce under these artificial conditions that care must be taken to feed them at all seasons, especially in winter.

THE FOX SQUIRREL (Sciurus niger and its relatives)

(For illustration, see page 547)

THE RUSTY FOX SQUIRREL (Sciurus niger rufiventer)

(For illustration, see page 547)

Three species of tree squirrels inhabit the varied forests of eastern North America, each having its marked individuality expressed in color, size, and habits. All occupy a wide territory with varying climatic conditions, to which each species has responded by becoming modified into a series of geographic races, or subspecies. The red and the gray squirrels have already been described and it remains to give an account of the largest and in some respects the most remarkable of the three, the fox squirrel.

No other species of North American mammal can show such an extraordinary contrast in color among its subspecies as that between the rusty yellowish animal of the Ohio and upper Mississippi Valleys, and the handsome blackish one of the Southeastern States, both of which are pictured in the accompanying illustration.

The distribution of the fox squirrel is limited to the forested parts of the Eastern States. There it ranges from the Atlantic coast to the border of the Great Plains, and from southern New York and the upper Mississippi Valley southward to Florida, the Gulf coast, and across the lower Rio Grande into extreme northeastern Mexico.

Variations in the character of the haunts of the different subspecies of this squirrel almost equal their differences in color. In the upper Mississippi and Ohio Valleys the rusty-colored race frequents the upland woods, where the nut-bearing hickory trees characterize the forests. In the South the dark-colored squirrels have more varied homes, either amid the live oaks draped in long Spanish moss, in the mysterious cypress forests of the swamps, or out in the uplands among the southern pines.

In early days fox squirrels were plentiful, but never equaled the numbers of the gray squirrel. They appear always to have been more closely attached to their own district, for we have no records of the great migrations so notable in the other species.

Fox squirrels are not only distinguished from gray squirrels by their color, but are also nearly twice their size, commonly attaining a weight of two and sometimes nearly three pounds. They are the strongest and most heavily proportioned of all American squirrels. A deliberation of movement going with heaviness of body is in marked contrast to the graceful agility of most other tree squirrels. On the ground they walk with a curiously awkward, waddling gait, and even when hard pressed climb trees with none of the dashing quickness shown by other species. They often move about on the ground by a series of bounds, and at such times, with broad, feathery tails undulating in the air, present a most graceful and attractive sight.

Fox and gray squirrels occupy the same districts throughout most of their ranges, but often become so segregated locally that the grays may be found almost exclusively along bottom-lands and the fox squirrels on the higher ridges, but there is no hard and fast separation of haunts and the two forms usually share the same woodlands.

Much time is spent by fox squirrels on the ground searching for food. When danger approaches, in place of promptly taking refuge in a tree, as is a common habit with most tree squirrels, they retreat along the ground, mounting a stump or log now and then, to look back at a suspected intruder, whose footsteps they can hear at a long distance. If the hunter is without a dog they may run away and be lost. A dog soon forces them up a tree and if a knot-hole or other hollow is available they at once take refuge in it. Otherwise they hide skillfully in bunches of leaves high in the top or lie flat on a limb or against the trunk, slyly moving to keep on the opposite side as the hunter draws near. In the Mississippi Valley during the crisp days when the hickory nuts are falling and the trees are decked in all the glories of autumn foliage, few sports afield yield more pleasurable sensations than fox-squirrel hunting.

The fox squirrels become fatter than most of their kind and their flesh is not so dry, although all furnish appetizing meat. Owing to their size and the quality of their flesh, they have been such desirable game animals that with the constantly growing number of hunters and the destruction of forests they have already disappeared from large areas where formerly abundant and are in real danger of extermination in the not-distant future. They are among the most notable and attractive of the forest animals in the Eastern States, and before it is too late every effort should be made to protect them from overshooting. With reasonable conservation they will continue to thrive and keep some of the old-time primitive spirit in our woods. Formerly they had the same predilection as the gray squirrel for the farmers’ corn fields and were under the ban, but their numbers are now so reduced that they give little trouble in this way. In some city parks where they have been introduced, they soon become tame and do well, except that in losing their fear of man they become subject to many accidents.

Fox squirrels, like many others of their kind, have homes both in knot-holes or other hollows in tree trunks, and in bulky nests of sticks and leaves high up among the branches. Both kinds of nesting places are often located in the same tree, the owner living in the outside nest in warm weather and retiring to the shelter of the hollow trunk in severe weather or to escape an enemy. The young, two to four in number, are usually born in March or April, and it is not definitely known whether there is a second litter. These squirrels have a barking call as well as several other rather deep-toned chucking notes.

They are as omnivorous as any of their kind, eating many kinds of nuts, seeds, fruits, mushrooms, insects, birds, birds’ eggs, and other flesh food when available. The principal nuts in their haunts are hickory-nuts, beechnuts, walnuts, pecan nuts, and the seeds of pines and cypresses. Toward the end of summer and in fall they work busily gathering and storing food for winter in hollow trees, in old logs, about the roots of trees, and in any other snug place where it may be kept safely until needed. Many single nuts are buried here and there in little pits three or four inches deep dug in the soft surface of the earth under the trees. These scattered stores are located when needed by the acute sense of smell which the owners possess.

THE ABERT SQUIRREL (Sciurus aberti and its subspecies)

(For illustration, see page 550)

THE KAIBAB SQUIRREL (Sciurus kaibabensis)

(For illustration, see page 550)

Among the many kinds of squirrels which lend animation and charm to the forests of North and South America, none equal in beauty the subjects of this sketch—the Abert and the Kaibab squirrels. These are the only American squirrels endowed with conspicuous ear tufts, which character they share with the squirrels occupying the forests in the northern parts of the Old World from England to Japan. In weight they about equal a large gray squirrel, but are shorter and distinctly more heavily proportioned, with broader and more feathery tails.

Their range covers the pine-forested region of the southern Rocky Mountains in the United States and the Sierra Madre of western Mexico. The Abert squirrel and its several subspecies is the more widely distributed, being found from northern Colorado, south through New Mexico, Arizona, Chihuahua, and Durango. The Kaibab squirrel, which is even more beautiful than its relative, shows marked differences in appearance and yet is evidently derived from the same species.

The typical Abert squirrel lives in the pine forests along the southern rim of the Grand Canyon in northern Arizona, and the Kaibab squirrel lives in the pines visible on the northern rim of the canyon less than 15 miles away. It is confined to an islandlike area of pine forest above 70 miles long by 35 miles wide, on the north side of the canyon, on the Kaibab and Powell plateaus, directly across from the end of the railroad at the Grand Canyon Hotel. The two species live under practically identical conditions as to vegetation and climate.

In these sketches of our mammal life I have repeatedly noted the effect of changing environment in modifying the animals subject to it. In the present case the change in the squirrels on the north side of the Grand Canyon has evidently been brought about by that powerful factor in evolution known as isolation. Cut off from their fellows by the deepening canyon of the Colorado, Kaibab squirrels have occupied a forest island ever since, with the resulting change in characters we now have in evidence.

The home of both the Abert and the Kaibab squirrels is almost entirely between 6,000 and 9,500 feet altitude, on the mountain slopes and high plateaus overgrown with a splendid open forest of yellow pine mixed in many places with firs and aspens. Occasionally, as food becomes scarce in their ordinary haunts, they range up into the firs or down into the oaks and piñon pines. In winter their haunts are buried in snow, but in summer on every hand present lovely vistas among the massive tree trunks, varied here and there by gemlike parks. Everywhere the ground is covered with grasses and multitudes of flowering plants. In the wilder parts of this fascinating wilderness roam bears, mountain lions, wolves, deer, and wild turkeys, and only a few decades ago still wilder men, belonging to some of our most dreaded Indian tribes.

Although these squirrels commonly make use of large knot-holes or other hollows in trees, they regularly build high up in the branches bulky nests of leaves, pine needles, and twigs and line them with soft grass and shredded bark. Sometimes several full-grown squirrels may be found occupying one of these outside nests, probably members of one family. They are active throughout the year, but remain in their nests during storms and severe winter weather. In northern Arizona I have known them to stay under cover for a week or two at a time in midwinter.

The young appear to be born at varying times between April and September. Although not definitely known, it seems probable that they have two litters of from three to four young each season.

The seeds and the tender bark from the terminal twigs of the yellow pine (Pinus ponderosa) furnish their principal food supply. During periods when pine seeds are not available the squirrels cut the ends of pine twigs, letting the terminal part bearing the leaves fall to the ground, while the stem, several inches in length, is stripped of bark. Often at times of food scarcity the bark will be eaten for a considerable distance along the outer branches, almost like the work of porcupines. The ground under the pines where the squirrels are at work is sometimes almost covered with the freshly dropped tips of branches.

The Abert squirrels also eat the seeds of Douglas spruce, of the piñon pine, acorns, many seeds, roots, green vegetation, mushrooms, birds’ eggs, and young birds. Now and then they rob cornfields planted in clearings, but they do little damage to crops. Some years they are extremely numerous and are in evidence everywhere; again they become scarce and so wary that it is difficult to see one, even where its fresh workings are in evidence.

Both these squirrels have a deep churring or chucking call, sometimes becoming a barking note resembling that of the fox squirrel. They also have a variety of chattering and scolding notes when excited or angry. At times they become almost as aggressive as the red squirrel and come down the tree trunk or to a lower branch, whence they scold and berate the object of their disapproval.

When much alarmed they are expert at hiding among tufts of leaves near the ends of branches, on tops of large limbs, or behind trunks. They will remain hidden in this way for an hour or more, patiently waiting for the danger to disappear, but one is often betrayed by the wind blowing the feathery tip of its tail into view.

On the ground the tail is usually carried upraised in graceful curves. Here these squirrels spend much time among fallen cones and in digging for roots and other food. When they walk they have an awkward waddling gait, but when they are alarmed, or desire to move more rapidly for any cause, they progress in a series of extremely graceful bounds, which show the plumelike tail to good advantage. When the Kaibab squirrel is moving about on the ground its great white tail is extraordinarily conspicuous in the sunshine. This repeatedly drew my attention to these squirrels, even at such long distances that they would otherwise have been overlooked.

Although so heavily built, these squirrels are adept in leaping from branch to branch and from tree to tree. On one occasion a branch on which an Abert squirrel was standing near the top of a pine tree was struck by a rifle ball; the squirrel promptly ran to the end of a large branch about fifty feet from the ground, and although no tree was anywhere near on that side, leaped straight out into the air, with its legs outspread just as in a flying squirrel. It came down in a horizontal position and struck the ground flat on its under side and the rebound raised it several inches. Without an instant’s delay it was running at full speed across a little open park and disappeared in the forest on the other side. I was standing only a few yards to one side of the falling squirrel and the widely spread feet and legs were perfectly outlined against the sky. It was evident that this squirrel and probably all of its kind appreciate that such an attitude will help break the force of the descent. This suggested the possibility of a similar habit having influenced the origin of the flying squirrel’s membranes.

One summer day in the Sierra Madre of western Durango I sat on a mountain slope watching for game. Below me stood the hollow-topped stub of an oak, the top being on a level with my eyes and about twenty yards away. Soon after I arrived the heads of four half-grown squirrels of the Abert family appeared in a row at the upper border of the opening, their bright eyes turning on all sides. Suddenly a hawk glided by, one of its wing tips almost brushing the noses of the squirrels. Instantly they vanished from sight and a noise of scratching and frightened chattering continued for several minutes, as though they were burying themselves under the nest. About twenty minutes later the boldest of the family showed the tip of his nose at an opening in a hollow branch near the top of the stub, but it required another ten minutes for him to venture forth his head. Finally, becoming confident that no danger threatened, he came out on the limb and deliberately stretched himself, yawning as widely as his little mouth would permit, after which he flirted his tail and frisked over to the trunk of the stub, where he began frolicking about with all the abandon of a kitten at play. When I departed his more timorous companions were still peering fearfully out of the hole, anticipating the return of the dreaded hawk.

THE FLYING SQUIRREL (Glaucomys volans and its relatives)

(For illustration, see page 551)

No one can see one of our small flying squirrels in life without being charmed by its delicate grace of form and velvety fur, nor fail to note the large black eyes which give it a pleasing air of lively intelligence. Flying squirrels are distinguished from all other members of the squirrel family by extensions of the skin along the sides, which unite the front and hind legs, so that when the animal leaps from some elevated point with legs outspread the membrane and the underside of the body present a broad, flat surface to the air. This enables it to glide swiftly down in a diagonal course toward a tree trunk or other vertical surface on which it desires to alight. It is able to control its movements and to turn with ease to one side or the other, or upward before alighting. When gliding down a wooded hillside or through thick growths of timber, it is thus able to avoid obstacles and alight on the desired place.

Flying squirrels are circumpolar in distribution. In the Old World they occupy forested areas in eastern Europe, and nearly all of Asia. In the New World they are peculiar to North America, where they frequent nearly all the wooded parts from the Arctic Circle to the Mexican border, and in forests in Mexico along the eastern border of the highlands as well as through Chiapas and Guatemala. In Asia, the center of development of these interesting rodents, many extraordinary forms occur. Some are giants of their kind, measuring nearly four feet in total length. In America there are two groups of species, the smaller and better known of which, the subject of this sketch, occupies the eastern United States and southward. The northern and western animals are larger, some of them more than twice the weight of the eastern species.

In many parts of the United States flying squirrels are common and even abundant, but their habits are so strictly nocturnal that they are infrequently seen. They make their homes in woodpecker holes, knot-holes, and hollows in limbs, and trunks of trees and stubs. In addition they take possession of many odd places for residence, among which may be mentioned bird-boxes, dove-cotes, attics, cupboards, boxes, and other nooks in occupied or unoccupied houses that are located within or at the borders of woods.

They also make nests of leaves, lining them with fine fibrous bark, grass, moss, fur, or other soft material placed securely in the branches or in forks in trees. They often remodel old bird or squirrel nests into snug homes for themselves. The size and construction of these outside nests vary according to the locality and the material available.

As a rule, the nests are small and accommodate only a single pair with their young, and sometimes hold only a single individual, but numerous exceptions to this have been observed. In southern Illinois fifty flying squirrels were discovered in one nest in a tree; in Indiana fifteen were found in a hollow stump; and near Philadelphia thirty were evicted from a martin box they had usurped.

In the southern part of their range flying squirrels are active throughout the year, but in the North they become more or less sluggish if they do not actually reach the stage of real hibernation during the severest weather.

Their food is extremely varied and includes whatever nuts grow in their haunts, as beechnuts, pecans, acorns, and others, with many kinds of seeds, including corn gathered in the field, and buds, and fruits of many kinds. They also eat many insects, larvæ, birds and their eggs, and meat. Taking advantage of their known liking for bird flesh, they may frequently be caught by concealing a trap on top of a log in the woods and scattering bird feathers over and about it. Trappers for marten and other forest fur-bearers are much annoyed in winter by the persistence with which the flying squirrels search out their traps and become caught in them, thus forestalling a more valued capture. Trappers in Montana who run long lines of traps for marten through the mountain forests capture hundreds of these squirrels in a single season.

Flying squirrels have several notes, one of which is an ordinary chuck, chuck, much like that of other squirrels. They also utter sharp squeaks and squeals when angry or much alarmed, and a clear musical chirping note, birdlike in character, which is frequently repeated for several minutes in succession and is undoubtedly a song.

These beautiful little animals become the most delightful of pets, as they are notable for extraordinary playfulness and a readiness to accept man as a friend. Many interesting accounts have been published concerning the affectionate attachment they form for their human hosts and the amusing and tireless activity they show at night. By day they remain sound asleep, rolled up in a furry ball in some dark corner.

They are known to have a litter of from two to six young in April, and young are born at various times throughout the summer, but it is still unsettled whether there is more than one litter a year. The mother is devoted to the young, and if driven from them will keep close by at the risk of her life, showing much anxiety and readiness to do what she can to protect them. One instance well illustrates this maternal care. From a nest in a hollow stub the helpless young were taken and placed on the ground at its base, while the despoiler of the home stood by to observe the result. The mother soon returned and not finding her family in the nest promptly located them on the ground. Quickly descending, she took one in her mouth, carried it to the top of the stub and, launching into the air, sailed to a tree thirty feet away, up which she carried her baby and placed it safely in a knot-hole. The trip was quickly repeated until the family was reunited in its new location.

At night the curiosity of flying squirrels about strange things and their mischievous activities are often most entertaining, and sometimes exasperating. Whatever is accessible within their territory is certain to be thoroughly explored. A large apartment building, seven stories high, in Washington stands on the border of the woods of the Zoological Park. During one summer night a friend occupying an apartment on the seventh floor of this building, fronting the park, observed some movement on one of his window sills and by later observation and by inquiry among the other residents learned that flying squirrels were habitually climbing all about the high walls to the top of this building, using it and some of the rooms as a nightly playground. Several occupants of apartments in different parts of the building regularly placed nuts of various kinds on the window ledges for them, and now and then were amused to find that during the night the squirrels had carried away some of their nuts, but had replaced them with other kinds, sometimes brought from a window at a considerable distance on another side of the building. The presence of these squirrels was warmly welcomed and furnished much interest to their hosts.

The constant activity of these little animals at night enables owls and cats to capture many, but their small size and the shelter of their homes by day will prevent their serious decrease in numbers so long as suitable forests remain to supply their needs.

THE BLACK-FOOTED FERRET (Mustela nigripes and its relatives)

(For illustration, see page 551)

Of all the varied forms of mammalian life in America, the black-footed ferret has always impressed me as one of the strangest and most like a stranded exotic. It is about the size of a mink, but, as the illustration shows, is entirely different in appearance and has the general form of a giant weasel. It has no close relative in America, but bears an extraordinarily close resemblance in size, form, and color to the Siberian ferret (Mustela eversmanni).

The black-footed ferret occurs only in the interior of the United States, closely restricted to the area inhabited by prairie-dogs, from the Rocky Mountains eastward and from Montana and the Dakotas to western Texas. It is known also west of the mountains in Colorado. Like others of the weasel tribe, it must have a wandering disposition, since one was captured at 9,800 feet altitude, and another was found drowned at 10,250 feet in Lake Moraine, Colorado.

These ferrets exist as parasites in the prairie-dog colonies, making their homes in deserted burrows and feeding on the hapless colonists. In Kansas their presence in certain localities appears to have been effective in exterminating prairie-dogs, and similar activities may account for the deserted “dog towns” which are not infrequently observed on the plains with no apparent reason for the absence of the habitants.

They do not appear to be numerous in any part of their range and little is known concerning their habits. Now and then they are seen moving about prairie-dog “towns,” passing in and out of the burrows at all hours of the day, but it is probable that they are mainly nocturnal. This probability is strengthened by the extreme restlessness shown at night by captive animals. With the occupation of the country and the inevitable extinction of the prairie-dog over nearly or quite all of its range, the black-footed ferret is practically certain to disappear with its host species.

It has the same bold, inquisitive character shown by the weasel, and when its interest is excited will stand up on its hind legs and stretch its long neck to one side and another in an effort to satisfy its curiosity. When surprised in a “dog town” it commonly retreats to a burrow, but promptly turns and raises its head high out of the hole to observe the visitor. As a result ferrets are readily killed by hunters. When one is captured it will at first hiss and spit like a cat and fight viciously, but is not difficult to tame.

Although mainly dependent upon prairie-dogs for food, there is little doubt that ferrets, after the manner of their kind, also kill rabbits and other rodents in addition to taking whatever birds and birds’ eggs may be secured. In one instance a black-footed ferret lived for several days under a wooden sidewalk in the border town of Hays, Kansas, where it killed the rats harboring there.

THE LARGE WEASELS, OR STOATS (Mustela arcticus and its relatives)

(For illustration, see page 554)

The weasel family includes not only the true weasels, but numerous other carnivores, as the sable or marten, mink, ferret, skunk, and land and sea otters, all of which rank among our highly valued fur-bearers. The large weasel may be distinguished from others of its family by the small size and the snakelike proportions of the flattened and pointed head, combined with a long, extremely slender neck and body and a comparatively long tail. The best known of these animals are the stoat of the northern parts of the Old World (Mustela erminea) and its close relative in northern North America (Mustela arcticus), the winter skins of which furnish the famed ermine, once sacred to the trappings of royalty.

The northern weasels are strongly marked by their habit of changing their brown coat to one of snowy white at the beginning of winter. To the south the change becomes less complete as the winter snows decrease, and south of the limit of snow the brown coat is retained throughout the year. The time of change depends on the coming of the snow and varies with the year, and the time of resumption of the brown coat in spring depends in the same way on the season. The white winter coat of the larger and medium-sized species is accompanied by a strongly contrasting jet black tip to the tail.

Weasels are circumpolar in distribution and occupy nearly all parts of Europe, Asia, and North and South America, the greatest number and variety of species occurring in North America. Surprisingly enough, the largest of these eminently northern animals is found in the forests of the American tropics. The Arctic weasel ranges to the northernmost polar lands of North America, where its presence has been recorded many times by ice-bound explorers. Other species are more or less generally distributed over the remainder of the continent. In Mexico I have found them from sea level to above timberline, at more that 13,000 feet altitude on the high volcanoes.

The strong personality of the weasels as a group is based mainly on their extraordinary celerity of movement, their courage, and their insatiable desire to kill. They are not satisfied with supplying the call for food, but whenever opportunity arises kill from sheer lust of slaughter.

Their slender forms enable them to follow their prey to the remotest depths of their retreats, and that all rodents have an abiding horror of them is shown by the effect of a weasel’s appearance. Rabbits, although many times their size, become easy victims, and in one instance when a large rat, which had fought its human captor viciously, was put in a cage with a weasel, it at once lost all its courage and permitted itself to be killed without an effort at defense.

Weasels are wonderfully endowed for their predatory work and are undoubtedly the most perfectly organized machines for killing that have been developed among mammals. Their keen eyes are constantly alert to observe everything about them, their ears are attuned to catch the faintest squeak of a mouse or cry of any other small animal, and their powers of scent are very great. When hunting they dart in and out of the holes of rodents, among crevices in the rocks, or through brush piles, pausing now and then to stand upright on their hind feet, the head swaying to and fro as they peer about. The squeak of a mouse starts them instantly in search of it, and like a dog they trail rabbits and other rodents by scent.

As a rule, weasels are terrestrial, but in wooded country they climb trees and leap from branch to branch with all the ease of squirrels. In most localities they are not common, but now and then, where conditions are peculiarly favorable, they become numerous. At one naturalist’s camp in the upper Yukon they were surprisingly abundant, so much so that more than forty were caught in a few days in traps set among broken rocks. There they were extremely bold, hunting for their prey among the rocks within a few feet of the trappers.

The prey of weasels includes almost every kind of small rodent and bird living within their territory. They feed especially upon northern hares, cottontails, conies, ground squirrels, chipmunks, tree squirrels, wood rats, mice, lemmings, quail, ptarmigan, spruce and ruffed grouse, ducks, and numberless other small species. They are also very destructive to domestic fowl, often killing thirty or forty in a night. They unhesitatingly attack rodents many times their own weight.

Once when hunting on the open plain near the southern end of the Mexican table-land, I saw at some distance what appeared to be a brown ball rolling about on the ground. This was soon determined to be a weasel fastened to one of the large and powerful pocket gophers of that region. The weasel had its teeth set in the back of the neck of the gopher, while the latter was blindly trying to tear itself loose. I fired an ineffectual shot at the weasel and it vanished like a flash in the open tunnel of the gopher. As I drew near, the gopher, still in fighting mood, faced me with bared teeth. Later, when I removed its skin, I found that the weasel had torn loose the attachment of the heavy neck muscles to the back of the skull until only a thin layer remained to protect the spinal column. This had been accomplished without breaking the thin, but extremely tough, skin of the gopher.

When a weasel is attacking an animal which resists, like a large ground squirrel, it raises its head and sways its long neck back and forth, its eyes glittering with excitement as it watches for an opening to spring forward and seize its prey. Its attack is always aimed at a vital point, commonly the brain, the back of the neck, or the jugular vein on the side.

Weasels dig their own burrows under the shelter of slide rock, ledges, stone walls, stumps, and outbuildings, or they occupy hollow trees and the deserted burrows of other animals. In nests thus safely located they have one litter containing an average of from four to six, but sometimes numbering up to twelve, young a year. They are born at any time from April to June, according to the latitude. The number of young in a litter is enough to render weasels very abundant, but this is rarely the case, and raises the question as to the influence which holds their number in check.

They are both nocturnal and diurnal, apparently in almost equal degree, since they are frequently observed hunting in the middle of the day, while their nocturnal raids on poultry houses testify to their activities at night. When hunting they appear like sinister shadows and are persistent in pursuit. The young commonly remain with the female until nearly or quite grown and follow her closely on hunting-trips. It is interesting to see a pack of these deadly carnivores working, the mother leading and the young skirmishing on all sides, now spreading out, now closing in, like a pack of miniature hounds. On these family hunting parties, however, they usually keep close to the rocks, logs, brush, or other cover.

Themselves subject to the law of fang and claw, weasels are killed and eaten by wolves, coyotes, foxes, and various birds of prey. Their very lack of fear perhaps in many cases leads to their destruction.

These representatives of the primitive woodland life continue to occupy practically all of their original range. They visit farms in all parts of the country and I have seen them near the outskirts of Washington.

It is well that weasels are not abundant, for beasts with such innate ferocity and love of killing would otherwise be a menace to the existence of many useful species of birds and mammals, especially the game birds. In many places they live almost entirely on mice, and there they should be left unmolested; but whenever they locate in the vicinity of a chicken yard the owner will do well to take proper measures for protection.

THE LEAST WEASEL (Mustela rixosus and its relatives)

(For illustration, see page 554)

In addition to the larger members of the tribe briefly described in the foregoing sketch, the true weasels include another group of species, so small they may appropriately be termed the dwarfs of their kind. They vary from a half to less than a fourth the size of the larger weasels, but have the same characteristic form and proportions, except that the tail is very short and never tipped with black. Like the larger species, they change their brown summer coat for white at the beginning of winter and back again in spring.

The least weasels are also circumpolar in distribution, but are limited to the northern parts of Europe, Asia, and North America. In England and other parts of the Old World the group is represented by the well-known species Mustela vulgaris. In North America several species are known which, between them, share all the continent from the Arctic coast south to Nebraska and Pennsylvania. On the desolate islands extending from the mainland far toward the Pole their place seems to be taken by the ermine.