Mule Deer Odocoileus hemionus (Rafinesque)

Description:   Mule deer can be distinguished from other Kansas members of the family Cervidae by: 1) reddish-brown back and sides in summer that become grayish-brown in winter, 2) darker mid-dorsal region, and lighter sides, 3) white belly, throat and chin, 4) a large gray-white rump patch that contrasts strongly with the darker back and sides, 5) short tail, tipped with black, 6) large ears, and 7) antlers (males only) with Y-shaped forks (white-tailed deer have only a single curving antler beam bearing unforked tines). Antlers are shed during winter, and in spring new growth begins to restore the antlers.

Size:   Adults may attain the following dimensions: total length 1160-1800 mm; tail 110-230 mm; hind foot 325-590 mm; ear 120-250 mm; weight 50-200 kilograms. Mule deer are larger than white-tailed deer, and less than half the size of elk.

Range and Habitat:   Before settlers arrived in Kansas, mule deer were abundant in the western two-thirds of the state. They prefer river bottoms and flood plains, canyons, and rolling hills rather than open prairie. By 1937 the population of mule deer had reached a low ebb, and only a few remained in the far western drainages of the Cimarron, Smokey Hill, and Solomon rivers. Restocking combined with expansion of the remaining wild stock has greatly improved the status of mule deer in western Kansas, and they are now abundant.

   In mule deer the rut begins in late September and continues into December, with a breeding peak in late October to early 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. Gestation takes about 200 days, and the fawns (usually twins) are born in late May or June. The fawns are spotted at birth, as with other kinds of deer, and average weight is approximately 3.7 kilograms. They remain hidden except when the doe nurses them. Within a week after birth the fawns begin to follow the doe, and shortly begin to sample solid food. Fawns lose their spotted coats at eight to ten weeks of age, earlier than do white-tailed deer fawns. They continue to nurse for three to five months, at which time they weigh 25 to 35 kilograms. Female fawns on good range may become sexually mature at this age, but male fawns 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.

Color photo by David M. Watson.   Copyright 1999.   All rights reserved.

Habits:   In winter, mule deer tend to form herds, the size of which depends on terrain and weather. On broken landscapes or in severe winter weather, mule deer may migrate some distances to reach winter range with suitable forage, and herd size tends to be larger under these conditions. In spring and summer they are more widely dispersed. When disturbed while bedded down, mule deer spring up, pause a moment to look about, and then flee. They have a bounding gait when fleeing up steep hills and canyons that is shared with no other North American deer. Mule deer have an acute sense of hearing and smell. They are far sighted, but tend to focus on movement rather than form.

Food:   Mule deer feed mostly at night and return to heavy or rough cover during the day. They are primarily browsers, feeding upon shrubs, tree twigs, and some forbs and grasses. In Kansas they often consume corn, milo, soy beans, and alfalfa, and may cause some local crop damage.

Remarks:   Currently, mule deer in Kansas do quite well in close proximity to humans. Their status in Kansas seems secure at this time, although some farming practices reduce their habitat.

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