NATIONAL PARK SERVICE Wildlife Portfolio of the Western National Parks

CALIFORNIA MULE DEER occur abundantly in Sequoia, Kings Canyon, and Yosemite National Parks. Under the protection afforded these animals by the National Park Service—no hunting or shooting of deer being allowed in our national parks—they have increased and multiplied there, so that the surplus overflows and provides hunting in the areas surrounding the parks.

This species has a robust body and is considerably larger than the white-tailed deer of the eastern United States and somewhat smaller than the Rocky Mountain mule deer. An average adult buck has a total length of about 57 inches and a black-tipped tail about 6-1/2 inches long. A fair-sized buck stands about 40 inches high at the shoulder and weighs between 150 and 200 pounds. Females are smaller and lighter than males.

Deer have distinct summer and winter coats. In summer the hair is reddish brown; in winter it is a fairly dark gray, commonly referred to as the "blue" coat. (See illustration on page 60.)

The evenly forked, widespreading, massive antlers are typical in all races of mule deer. Normally, these are borne by the males only and are shed each year, usually between January 15 and February 25 at the end of the "rut" or mating season. Each spring new antlers sprout and grow. While growing they are covered with a soft velvet (see illustration), are warm to the touch, and are evidently quite tender because when feeding together at this time of the year the bucks are careful to avoid striking them against those of other bucks or any hard or rough object. It is amusing to watch the care exercised in this regard, in view of the fact that a few months later, when the antlers are fully grown, hardened, and polished, the bucks may take part in fierce combats and use the antlers to defeat and sometimes even to kill each other.

The gait of the mule deer is not so smooth and graceful as that of the white-tailed deer. It is characterized by a bold, bounding action which serves two functions. First, it enables the mule deer to travel rapidly over rough broken rocks, bushes, and boulders which are frequently encountered in the West. Secondly, the high jumps of this bounding gait temporarily give the animal an elevated vantage point from which it can see any pursuing enemy.

The bucks often run separately from the does and fawns during the summer, but in the breeding season each buck keeps jealous watch over his "harem." Normally bucks are not the leaders of mixed bands of deer. Throughout most of the year the real leader is some wise old doe, usually the mother of fawns in the group, that knows the best feeding grounds where forage is plentiful.

PHOTOGRAPH, YOSEMITE NATIONAL PARK, AUGUST 1, 1929.

THE FAWNS, born late in June or early in July, are reddish-brown, spotted at birth with creamy white. Usually there is but one fawn in a litter, but often twins are born. Beginning July 9, 1928, in Yosemite, I watched a pair of twin fawns from the time of their birth, which was actually witnessed, and weighed and measured them each day for the succeeding 10 days. Then they could outrun me, so I was unable to catch them. I found that at birth the fawns weighed about the same as an average human baby and that for the first week of their lives the daily gain was about the same as in a human infant. When 24 hours old a typical female fawn weighed 6-1/4 pounds and a male fawn 7-1/2 pounds. The "spots" are lost in September when the summer coat is shed.

Most of the food of mule deer is obtained by browsing rather than grazing, although these animals eat considerable quantities of grass at certain times, especially in the early spring. The leaves and young shoots of many shrubs and trees are eaten at all seasons, deer brush, manzanita, and snowbrush being favorites. Acorns are frequently eaten in early winter.

As the colder days of fall approach, the bucks frequently choose a sunny spot in the forest for a bed. There, after pawing out any protruding rock or branches, they curl up and go to sleep for a daily sun bath. During the winter I have found that some bucks often seek a bed of dry leaves under a sheltering rock or tree rather than bed down in the snow, although they will take the snow bed if nothing better is available. In the heat of summer they will choose a cool bed under the shade of some dense pine tree.

The most important natural enemies of the California mule deer are the mountain lion, the mountain coyote, and the human hunter. Both the mountain lion and man seem to exercise a preference for deer in the best physical condition, although there are many humans as well as cougars that take the first available deer. Contrasted to this, it has been my experience that the coyote exercises a selective pruning effect on deer in California in that the majority of deer captured by coyotes are weak, sickly, or diseased individuals, probably because the coyote can more easily capture these. It should be pointed out that the elimination of such diseased deer may benefit the species by preventing contagion of healthy individuals.

Woodticks are probably the most important external parasites of the California mule deer, while lungworms and the nasal botfly infest the lungs and nasal passages of deer. A parasitic eye worm of the genus Thelisa has recently been found infesting the deer at Sequoia National Park.

In spite of natural enemies, disease, parasites, and human hunters, the mule deer in California are increasing.

PHOTOGRAPH, YOSEMITE NATIONAL PARK, OCTOBER 30, 1929.