White-tailed deer

Appearance

The deer's coat is a reddish-brown in the spring and summer and turns to a grey-brown throughout the fall and winter. The deer can be recognized by the characteristic white underside to its tail. It raises its tail when it is alarmed to warn the predator that it has been detected.

An indication of a deer age is the length of the snout and the color of the coat, with older deer tending to have longer snouts and grayer coats. White-tailed deer's horizontally slit pupils allow for good night vision and color vision during the day.

Naming

The scientific name of white-tailed deer is "Odocoileus virginianus". There are 38 subspecies in the world.

Distribution

In North America, the species is widely distributed east of the Rocky Mountains as well as in southwestern Arizona and most of Mexico, aside from Lower California.

It is mostly replaced by the black-tailed or mule deer from that point west except for in mixed deciduous riparian corridors, river valley bottomlands, and lower foothills of the northern Rocky Mountain region from South Dakota west to eastern Washington and eastern Oregon and north to northeastern British Columbia and southern Yukon, including in the Montana valley and foothill grasslands.

Texas is home to the most white-tailed deer of any U.S. state or Canadian province, with an estimated population of over four million. Notably high populations of white-tailed deer occur in the Edwards Plateau of Central Texas.

Michigan, Minnesota, Iowa, Mississippi, Missouri, New Jersey, Illinois, Wisconsin, Maryland, New York, North Dakota, Ohio, Pennsylvania, and Indiana also boast high deer densities.

Behavior

Males compete for the opportunity of breeding females. Sparring among males determines a dominance hierarchy. Bucks attempt to copulate with as many females as possible, losing physical condition, since they rarely eat or rest during the rut.

White-tailed deer have many forms of communication involving sounds, scent, body language, and marking. In addition to the aforementioned blowing in the presence of danger, all white-tailed deer are capable of producing audible noises unique to each animal.

Fawns release a high-pitched squeal, known as a bleat, to call out to their mothers. This bleat deepens as the fawn grows until it becomes the grunt of the mature deer, a guttural sound that attracts the attention of any other deer in the area.

A doe makes maternal grunts when searching for her bedded fawns. Bucks also grunt, at a pitch lower than that of the doe; this grunt deepens as the buck matures. In addition to grunting, both does and bucks also snort, a sound that often signals an imminent threat. Mature bucks also produce a grunt-snort-wheeze pattern, unique to each animal, that asserts its dominance, aggression, and hostility.

Another way white-tailed deer communicate is through the use of their white tail. When spooked, it will raise its tail to warn the other deer in the immediate area.

Habitat

White-tailed deer are generalists and can adapt to a wide variety of habitats. The largest deer occur in the temperate regions of North America.

Although most often thought of as forest animals depending on relatively small openings and edges, white-tailed deer can equally adapt themselves to life in more open prairie, savanna woodlands, and sage communities as in the Southwestern United States and northern Mexico.

Reproduction

Females enter estrus, colloquially called the rut, in the autumn, normally in late October or early November, triggered mainly by the declining photoperiod. Sexual maturation of females depends on population density, as well as availability of food. Young females often flee from an area heavily populated with males. Some does may be as young as six months when they reach sexual maturity, but the average age of maturity is 18 months. Copulation consists of a brief copulatory jump.

Females give birth to one to three spotted young, known as fawns, in mid- to late spring, generally in May or June. Fawns lose their spots during the first summer and weigh from 44 to 77 lb by the first winter.

Male fawns tend to be slightly larger and heavier than females. For the first four weeks, fawns are hidden in vegetation by their mothers, who nurse them four to five times a day. This strategy keeps scent levels low to avoid predators.

After about a month, the fawns are then able to follow their mothers on foraging trips. They are usually weaned after 8–10 weeks, but cases have been seen where mothers have continued to allow nursing long after the fawns have lost their spots as seen by rehabilitators and other studies. Males leave their mothers after a year and females leave after two.

Bucks are generally sexually mature at 1.5 years old and begin to breed even in populations stacked with older bucks.

Food

White-tailed deer eat large amounts of food, commonly eating legumes and foraging on other plants, including shoots, leaves, cacti, prairie forbs, and grasses. They also eat acorns, fruit, and corn.

Their special stomachs allow them to eat some things humans cannot, such as mushrooms and poison ivy. Their diets vary by season according to availability of food sources. They also eat hay, grass, white clover, and other foods they can find in a farm yard.

Though almost entirely herbivorous, white-tailed deer have been known to opportunistically feed on nesting songbirds, field mice, and birds trapped in mist nets, if the need arises. A grown deer can eat around 2,000 lb of vegetable matter annually. A foraging area around 20 deer per square mile can start to destroy the forest environment.

Predators

There are several natural predators of white-tailed deer with wolves, cougars, American alligators, jaguars and humans being the most effective natural predators. Aside from humans, these predators frequently pick out easily caught young or infirm deer, but can and do take healthy adults of any size.

Bobcats, Canada lynx, bears, wolverines, and packs of coyotes usually prey mainly on fawns. Bears may sometimes attack adult deer, while lynxes, coyotes, and wolverines are most likely to take adult deer when the ungulates are weakened by harsh winter weather.

Many scavengers rely on deer as carrion, including New World vultures, raptors, foxes, and corvids. Few wild predators can afford to be picky and any will readily consume deer as carrion.

Defense

White-tailed deer typically respond to the presence of potential predators by breathing very heavily and fleeing. When they blow, the sound alerts other deer in the area. As they run, the flash of their white tails warns other deer. This especially serves to warn fawns when their mother is alarmed.

Cultural

In the U.S., the species is the state animal of Arkansas, Georgia, Illinois, Michigan, Nebraska, Mississippi, New Hampshire, Ohio, Pennsylvania, and South Carolina, the game animal of Oklahoma, and the wildlife symbol of Wisconsin.