Description: A large-eared deer with a tail that is either all black above or black tipped. Total length of an average adult about 6 feet. Tail about 8 inches. The coat is reddish in summer and blue-gray in winter. Under parts and insides of legs lighter in color. Some forms of this species have a white rump patch, others none. The tail may be black-tipped, or black over the whole dorsal surface, but is more sparsely haired than that of other native deer and is naked over at least part of the under surface. Only the bucks have antlers. These are typical in forking equally from the main beam. They are shed every year.
mule deer
The mule deer is typical of the western mountains. Even in early days it was never found east of the Mississippi and now is seldom seen east of the Rockies. Only one species is recognized in the United States, although over its vast range are many subspecific forms. All are notable for the size of their ears, from which derives the common name “mule.” The black-tailed deer of the Pacific Coast, long considered a distinct species, is now rated a subspecies of the mule deer.
In a general way the deer of the United States may be divided into two groups, these separated geographically by the Continental Divide. East of this line is the territory occupied by the white-tailed group; westward of it live the mule deer. Inasmuch as species seldom stop abruptly at geographical lines, we find in this instance that a whitetail subspecies, locally known as the Sonora fantail, is found along the Mexican border as far west as the Colorado River, territory also occupied by desert-dwelling mule deer. In like fashion the mule deer of the Rocky Mountains can even now be seen in the Badlands of North Dakota, several hundred miles east of the Continental Divide and well within the western range of the plains white-tailed.
Though the two species mingle in places, they are easily distinguished from each other, even by the novice. Because in many cases the animal is seen only in flight, the manner of running is perhaps the most prominent field difference. The mule deer, adapted to living in rough country, bounds away in stiff-legged jumps that look rather awkward on the level but can carry it up a steep incline with surprising speed. The white-tailed, on the other hand, stretches out and runs at a bobbing gallop. Deer seldom take leisurely flight from a human, usually straining every muscle to leave their enemy as soon as possible. In the rough, broken country frequented by mule deer this tactic often makes considerable commotion.
I am reminded of a herd of an estimated 70 deer that I jumped on a steep mountainside in southern Utah. The crashing of brush, crackling of hooves, and noise of rocks kicked loose in their flight created the impression of a landslide.
Another easily seen field difference between mule and white-tailed deer is the dark, short-haired tail of the former as compared with the great white fan of the latter. The tail of the mule deer seems in no way to be used as a signal. In flight it is not wagged from side to side as is that of the white-tailed.
Antlers of the mule deer are unlike those of any other large game species inhabiting their range. They are impressively large as a rule and, because of the high angle at which they rise from the head, often look larger. The spread is wide in proportion to the height; thus it is not unusual for a well-antlered buck to be mistaken for an elk, especially at a distance. The antlers are unique in having a beam that forks equally to form the points. Thus a typical head might have five points, these being: the basal snag, a small tine rising from the beam near the head; and four points, two from the forking of each division of the beam. The western manner of counting the points consists of numbering those of one antler only; the method often used in the East counts all of the points of both. The number of points does not necessarily denote the age of a deer. Under normal conditions the antlers will increase in size and points with every new pair until maturity is attained. They will then grow to approximately the same size for several years. In old age, the antler development will usually dwindle with each succeeding year until, in senility, they may be as small as those of a young deer. The condition of teeth and hooves is a more accurate indication of age even though this method lacks prestige of the time-honored system of points.
It would seem, from the ease with which this big deer can be established in varying types of habitat, that it is in little danger of extinction. It is probable that the various subspecies will disappear before long because their range is rapidly being taken up by agriculture or lumbering. Given some protection, the species will endure in the higher mountains for many years to come.