White-tailed Deer Biology

(Odocoileus virginianus)

Description and Range:

Adult white-tailed deer are about three feet tall at the front shoulders. Maryland yearling bucks (males) weigh an average of 105 pounds; yearling does (females) average 90 pounds. During the warm months, deer possess reddish-brown hair. A grayish-brown coat with a thick undercoat replaces the reddish hair during the cold time period. The white-tailed deer’s distinctive white tail and white rump patch is readily visible when they bound away from real or perceived danger. White-tailed deer sprint up to 35 miles per hour and are able to leap over 8 foot tall barriers.

Only white-tailed bucks possess antlers. In extremely rare cases, does may grow antlers. Bucks use their hard antlers to establish dominance over other bucks during breeding season. Antlers are grown and shed each year. Antlers, which are composed of true bone, begin to grow in late March and early April. The growing antlers are covered with skin and blood vessels called velvet.

White-tailed deer can be found in every county in Maryland. White-tailed deer are also common throughout much of the United States, southern Canada and even parts of central America.

WT-Deer_DoeandBuck.jpgDoe (left) by John White and a buck with velvet antlers (right), by Kerry Wixted
Doe (left) by John White and a buck with
velvet antlers (right), by Kerry Wixted

Habitat:

Maryland white-tailed deer habitat includes most of the state except for open water and intensely developed urban areas (e.g. downtown Baltimore). Deer thrive in landscapes with wooded/brush sections and open areas such as cropland, pasture or landscaped yards. Deer use the wooded areas for food and cover, and open areas provide food. Landscapes with an abundance of edge habitat (areas where forested and open habitat meet) support prime deer habitats. Because of this, suburban sprawl creates ideal habitat conditions for white-tailed deer. When forested areas are converted into housing developments, portions are cleared for roads and home sites, while other sections remain forested. When open farmland is transformed into residential areas, new homeowners plant trees, shrubs and perennials. Both of these types of residential conversions provide excellent deer habitat. To learn more about managing deer damage, then click here.

The typical, annual average home range for white-tailed deer is considered about one square mile (640 acres). However, the sex and age of the deer and habitat types will influence varying size home ranges. Yearling males will move many miles while adult females usually have smaller stable, annual home ranges. Deer in good quality habitat will need to travel less than deer in poor quality habitat.

Diet:

Deer feed on nuts and berries, leaves, woody shoots and stems, grasses and cultivated crops. Some of their favorite natural foods include acorns, honeysuckle, poison ivy, green briar, young tree seedlings and mushrooms. Soybeans, corn and ornamental shrubs are several of their favorite foods planted by humans.

Deer have a four-chambered stomach that is required to digest the vegetation. Food first travels to the rumen that contains the bacteria and protozoans, which begin the digestive process. The reticulum circulates food back to the mouth so that the deer can chew the food again. The omasum functions as a pump and directs the partially digested food from the reticulum to the abomasum. This final chamber functions as a true stomach and completes the digestive process. Because of this special digestion process, it is generally not recommended to feed deer during the winter. Click here to view White-tailed Deer Facts​.

Reproduction:

Maryland white-tailed deer begin breeding in October and continue to breed through mid December. The shortening of day length (photo period) triggers the breeding season. Most does become pregnant during the first half of November. Because white-tailed deer are polygamous, one dominant buck can breed numerous does. Any receptive doe that does not become pregnant will cycle back into estrous (heat) in about 28 days and will mate again.

Fawns (baby deer) are born during May and June after a gestation period of about 200 days. Yearling does usually give birth to single fawns. Mature does in good physical condition frequently produce twins.

Newborn spotted fawns remain hidden and solitary for about three weeks. The doe visits her young only two to three times per day in order to nurse and groom the offspring. When the fawn is strong enough to run with the doe, it will follow its mother and begin to sample foods eaten by the doe. Fawns can live independently of their mother at about two months old.

Fawn_KWixted.jpgFawn hiding among ferns, by Kerry Wixted 

Sounds:

Deer typically make three different types of sounds: alarm, maternal, reproductive.

Alarm calls help to warn other deer of real or perceived danger. When a deer is surprised, it will snort by forcing out air rapidly from the nostrils. When fawns or young adults are captured by a predator or trapped, they will make a bleating or groaning sound.

Does also use low grunts to communicate with her young and to maintain contact. Fawns respond with a mew like sound. Fawns will also use bleats to get attention from the maternal doe. Communication between does and young help to maintain a close pair bond.

During the breeding season, bucks make grunt sounds while searching for receptive does and while tending does. Bucks also advertise their presence to prospective does and potential competitive bucks with grunts of varying pitch and volume.

Behavior:

Bucks are often solitary creatures aside from the breeding season and occasionally during the summer when they form bachelor bands. In the breeding season, bucks will actively seek out females to mate with as well as spar with other males to fight for the rights to breed.

Does, on the other hand, can often be seen traveling together particularly in the winter when food tends to be scarce. Often, fawns will remain with their mothers through the winter and into early spring. Typically, young bucks leave their mothers earlier than young does.

Management:

White-tailed deer are primarily managed by hunting in Maryland. Click here to learn more about hunting as an effective tool for white-tailed deer management. Click here to learn more about white-tailed deer management, in general.

For an information sheet on common deer sign, please click here​.

Photo Acknowledgements:

  • Doe by John White
  • Buck with velvet by Kerry Wixted
  • Fawn by Kerry Wixted
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