Mule deer can be distinguished from other members of the deer family in Kansas by their conspicuously long ears, small tail with a black tip over a white rump patch, and antlers (in males) with Y-shaped forks. The pelage is reddish-brown on the back and sides in summer but grayish-brown in winter. The mid-dorsum is darker, whereas the venter, throat, and chin are white.
The mule deer may be confused with the white-tailed deer, from which it differs in shape of antlers, size and color of tail, how the tail is held when running, and the color of the hindquarters. Occasional hybridization between the species results in offspring that are intermediate in features such as the antlers and tail.
The mule deer occurs in much of western North America from Alaska to Mexico. The species was abundant in the western two-thirds of Kansas before settlers arrived in the state. Excessive hunting led to their near extirpation by about 1900. By 1937, only a few mule deer remained in the far western drainages of the Cimarron, Smokey Hill, and Solomon rivers. Conservation and restocking, followed by dispersal of individuals from introduced herds, coupled with with expansion of the remaining wild stock, resulted in reestablishment of the mule deer throughout much of western Kansas. However, there is some evidence that the species is retreating westward as a result of competition with the more abundant white-tailed deer.
County Breakdown: County Name (# occurrences)
Clark (1), Comanche (1), Ellis (2), Finney (1), Gove (1), Hamilton (10), Jefferson (1), Logan (3), Meade (2), Osborne (1), Rawlins (3), Rush (9), Trego (2)
In Kansas, rut typically begins in late September and continues into December, with a breeding peak in late October and November. As in male wapiti, the neck and shoulders of male mule deer swell during the breeding season. They become quite belligerent and incautious while competing for does. Females are in estrous for only a few hours at a time but repeat their estrous cycle every 3 or 4 weeks until bred. Gestation lasts an average of 203 days, and the fawns (usually twins) are born in late May or June. The fawns are spotted at birth, as in other species of deer, and average weight is approximately 3.7 kg. They remain hidden, except when the doe nurses them, for several days, after which they begin follow the doe. Fawns lose their spotted coats at 8 to 10 weeks of age. Females may bread during their first year, but males do not attain breeding condition until the next season. They usually remain in the same herd with the female during the first winter and disperse the following spring.
Mule deer may be found in numerous habitats but seemingly are most abundant on shrubland where the terrain is broken and rough. They prefer river bottoms and flood plains, canyons, and rolling hills to open prairie. In winter, mule deer tend to form herds, the size of which depends on terrain and weather. On the Great Plains, mule deer tend not to be migratory although they may move several kilometers over the course of a year. During severe winter weather, herds may congregate in sheltered areas where food is plentiful. Activity is mostly nocturnal or crepuscular during warm months, becoming more diurnal in winter. Mule deer have a bounding gait that is shared with no other North American deer.
Mule deer feed mostly at night and return to heavy or rough cover during the day. They browse on a wide variety of woody plants but also graze forbs and grasses. In Kansas, they often consume corn, milo, soy beans, and alfalfa in addition to native plants.
Predators and Defense:
Predation in Kansas is heaviest on fawns, primarily by coyotes. The most important predators on adults are pumas, coyotes, and dogs. Other important sources of mortality are vehicular traffic and hunting.
Growth and Longevity:
Measurements of adult males, followed by those of adult females, are as follows: total length 1370-1800, 1160-1800; length of tail 150-230, 110-200; length of hind foot 410-590, 325-510; length of ear 120-250, 120-240; weight 50-215, 33-72 kg. Females reach maximum size in about 2 years, whereas males continue growing until they are 9 or 10 years old. Mule deer are larger than white-tailed deer but less than half the size of elk. Mule deer may survive up to 20 years in the wild, but such longevity is rare and population turnover is high.
The subspecific name that applies to populations of the mule deer in Kansas is Odocoileus hemionus hemionus.
The genus Odocoileus has been speculated to be of Old World origin. The earliest records in North America are from Arizona, California, and Kansas in the mid- to late Pliocene. Unambiguous specimens of the species Odocoileus hemionus are not available until after the Pleistocene.
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