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The Mammals of Texas -
Online Edition White-tailed Deer
Distribution in Texas. Suitable brushy or wooded country throughout the state. Habits. White-tailed deer occur almost entirely in the hardwood areas within their general range except for the southeastern section of Texas where the principal vegetation is a mixture of pines and hardwoods or nearly pure stands of pines. In the Chisos Mountains of Texas they occur in the mountains, whereas the mule deer occupies the lower foothills and broken deserts; in most other places this habitat relationship is reversed. For example, in the Guadalupe Mountains the whitetail occurs almost entirely in the foothills; the mule deer, in the higher mountains. White-tailed deer have a relatively small home range and cruising radius. Normally, when food conditions are adequate, the deer tend to stay in one locality for long periods. For example, in the Edwards Plateau region, where deer were belled in an experimental study, many of the marked deer remained on an area of 259 ha for at least 3 years. A few of them were found as far away as 8 km. Deer are most active just before sunset and again shortly after sunrise. It has been found in experimental trials that they are most easily observed in the hour just before dark. During the middle part of the day they are generally bedded down in some thicket or on some promontory where they are more or less protected. Under cover of darkness it is not uncommon for them to feed well into the night, but there is usually a period of resting and cud chewing during the middle part of the night. In regions heavily populated with deer their trails and beds, the latter usually scraped out places under the protection of overhanging boughs or at the bases of trees, are readily seen and give some clue to the density of the population. As with most other mammals, the feeding habits of whitetails vary from place to place and from season to season. E. L. Atwood listed more than 500 different plants utilized by whitetails in the United States. Availability determines in large measure what the animals will eat but if adequate food is available, the deer are dainty eaters and exercise considerable choice in the items taken. In the Chisos Mountains of Trans-Pecos Texas, whitetails feed extensively on mountain mahogany and other low shrubs. In the Edwards Plateau region the deer graze twice as much as they browse. There, 67% of their total feeding time was spent in grazing on forbs and grasses, 26% in eating fruits and mast, and only 7% in browsing. In South Texas, however, browse species make up the bulk of the diet. The 10 most favored foods as observed in the Edwards Plateau of Texas are grasses and weeds, Mexican persimmon, live oak acorns, live oak leaves, mesquite beans, oats or other grain, Spanish oak acorns, spike rush, Foresteria or elbow bush, and turkey pear. On the basis of food consumed, seven deer will eat about as much as one medium-sized cow. White-tailed deer are polygamous. The rut begins in early fall and continues through early winter. The onset of breeding varies considerably from one section of the country to another. In coastal Texas, for example, it is not uncommon for breeding to begin as early as September. In the Edwards Plateau, not more than 300 km distant, the peak of the breeding season is in November, whereas in the southern "brush country" section of Texas the peak is in late November and December. The fawns, usually one or two in number, are dropped after a gestation period of approximately 7 months and hidden by the female for 10 days to 2 weeks. She goes several times daily to nurse them but as soon as they are strong enough to follow her about they do so. The spots are retained until the fawns molt in early fall by which time they are usually weaned. Normally, sexual maturity is not reached in females until the second year but occasionally, when food conditions are excellent, female fawns mate the first fall and produce offspring the following spring when they themselves are only 1 year old. This appears to be unusual throughout most of their range, however. There is a relationship between testicular activity and the growth and shedding of antlers. The antlers begin their annual growth when the testes and accessory organs are inactive, harden and lose their velvet when these glands are enlarging, and are shed when they begin to decline. Castration following loss of the velvet results in shedding within 30 days. New growth, which occurs at the normal time, is abnormal in shape and the velvet is not lost. Growth ceases at the usual time and part of the growth, being somewhat fragile, may be lost by accident. Renewed growth activity follows in the spring. Eventually, an aggravated burr is produced. These events have been interpreted as indicating that antler growth is under the influence of a nontesticular hormone, possibly from the anterior pituitary, and antler hardening and subsequent loss of the antler is due to the action of a testicular hormone. One can estimate the age of whitetails by examination of the teeth. At 9 months of age the fawn will be acquiring the middle pair of permanent incisors while the remainder of the incisors as well as the premolars will be milk teeth. At this age one molar on either side of each jaw is well developed while the second is barely breaking through the gum. At the age of 1½ years all milk incisors have been replaced by permanent teeth. At least two molars are fully developed while the third may be in any condition from barely emerging from the mandible to fully emerged. At the age of 2 years the full set of permanent teeth is acquired. Beyond 2 years age determination is somewhat uncertain but can be roughly estimated by the wearing of the teeth. Wear of the teeth is gradual until at 5 years the ridges of enamel are no longer sharp, but rise slightly and gradually above the dentine. At still later ages the crowns of the premolars and molars rise only a short distance above the gums, and the grinding surfaces are worn practically smooth. Contrary to popular opinion, it is almost impossible to determine accurately the age of deer by the number of points on the antlers. For example, the shed antlers collected from one buck in Texas over a period of 5 years had each year either four or five points on each side. There is some correlation between age and diameter of the beam of the antler, however. The older bucks tend to have heavier antlers, but antler development is also so closely associated with nutrition that it is hazardous to make generalizations concerning age and diameter of the beam. Also, a certain amount of geographic variation is seen in antler development. White-tailed deer are the most important big game animals in Texas. In the face of an expanding human population this species has done remarkably well. It is estimated that our 1991 white-tailed deer population numbered more than 3.1 million in spite of heavy hunting pressure and approximately 474,000 were harvested by hunters in that year. On some ranges there is considerable competition for forage between white-tailed deer and domestic livestock. This is particularly true between deer and domestic goats. Competition between deer and cattle is not so severe. Where abundant in farming areas, deer often become pests and destroy such crops as peas, peanuts, wheat, oats, and other small grains. |
Description. A relatively small deer with
relatively short ears; all major points of the antlers
come off the main beam; tail relatively long, broad
basally, and white underneath; metatarsal gland small and
circular; females usually antlerless; upperparts reddish
brown in summer, bright grayish fawn sprinkled with black
in winter; face and tail usually lack blackish markings;
underparts white. Dental formula as in the