All about the White-tailed Deer

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 Jump down to: •Physical characteristics  •Antlers  •Behavior   •ReproductionHabitat 
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Male with velvet antlers.
(Alan D. Wilson / Nature’s Pics: cc by-sa 3.0)

Ask any child about deer and Bambi, the cute White-tailed fawn in Walt Disney’s famous animated movie, will surely come up. Some city folks count themselves lucky to have a Bambi visiting their yard and may even feed him. On the other hand are the gardeners desperate to protect their trees, shrubs and flowers. Love ’em or hate ’em, White-tailed Deer are elegant animals merely trying to survive in an increasingly urbanized world.

White-tailed Deer (Odocoileus virginianus) are mammals belonging to the order Artiodactyla (ART-ee-oh-DACK-tuh-luh, meaning even-toed animals) and the family Cervidae (SER-vuh-dee), which includes Moose, Elk and reindeer (known as Caribou in North America), among others. They’re native to the Americas and the most widely distributed hoofed animals in the Western Hemisphere. White-tailed Deer now number around 30 million in the United States and inhabit all states but Utah, Nevada and California. They’re most heavily represented east of the Rocky Mountains. They have no close relatives anywhere else in the world.

The word for the White-tailed Deer’s genus, Odocoileus, comes from Greek for “hollow tooth.” “Deer” comes from Old English dor, meaning “beast.” Like “Moose” and “sheep,” deer is both singular and plural.

White-tailed Deer evolved over millennia from small, antler-less, tropical herbivores to the animals we see today. Scientists have compared fossil records against DNA-dating and have established that White-tailed Deer date back to the mid-Pliocene Epoch. This was a period between 5.33 and 1.81 million years ago — a time of global cooling which led to the spread of grasslands and, in turn, created good deer habitat. The deer began to radiate northward from the tropics of Central America and South America, and by the Pleistocene Epoch (1.8 million to 10,000 years ago) they were common in eastern and central North America. White-tailed Deer now inhabit localized areas of Europe, having been introduced there in the mid-1800s.

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Whitetails are becoming increasingly urbanized. (© Robert Pernell)

The White-tailed Deer population has fluctuated significantly due to human activities. First, heavy trading by early settlers and American Indians reduced the number of deer. Then over-hunting for meat and sport dropped this country’s deer population in the 1800s to about 500,000. In some areas, White-tailed Deer disappeared altogether. The downward trend was steady until 1900 when a federal wildlife law, the Lacey Act, was enacted to prohibit interstate trafficking of wild game. That was followed within a few years by new laws in most states that further benefited the deer and their population began to steadily increase. The deer also benefited from the clear-cutting of forests to make way for farming and urban development. This allowed vegetation favored by deer to emerge, and it continues to this day — the more we clear, the more deer habitat we create. Today, there are more than 20 million White-tailed Deer, and humans and deer are increasingly living side-by-side.

There are numerous subspecies of White-tailed Deer. Taxonomists don’t agree on just how many. Depending on the source, there are somewhere between 30 and 40. Most subspecies have been named for the region they populate. For instance, there are the Florida Key Deer, the Dakota White-tailed, the Kansas White-tailed and even a Hilton Head Island White-tailed Deer. This naming pattern holds true for most of the subspecies in Mexico and South America, too, with such species as the Rain Forest White-tailed (southern Mexico) and the Northern Vera Cruz White-tailed.

Male White-tailed Deer are called bucks and females are does (DOZE). You may know the term “stag” for male deer, and that isn’t incorrect, but it’s more commonly used for larger members of the Cervidae family, like male Moose or Caribou.

Physical description
If you’ve never seen a White-tailed Deer “in person,” you’ll probably be surprised when you do. They’re much smaller than they seem in photos, where they often seem to be posing majestically in a grassy meadow, framed by a forest in the background and nothing nearby to serve as a comparison for judging their size.

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White-tailed Deer are small, as this young boy’s height shows by comparison.(© Alex Shalamove)

So, it may be surprising to learn that the shoulder height of an adult White-tailed Deer is about the height of a typical 5-year-old child — about 32 to 40 inches, with males being taller than females. Body length runs 52 to 95 inches. As for weight, occasionally a male might weigh up to 350 pounds, but typically they weigh no more than about 150 pounds. Females weigh around 90 to 100 pounds — by comparison, German Shepherd dogs weigh up to 100 pounds and a female English Mastiff can weigh between 120 and 200 pounds. White-tailed Deer living in cooler climates tend to be larger than those living in warmer climates.

White-tailed Deer get their name from their tail, which is fringed with white and has a white underside. This is barely seen unless the deer is running or disturbed, at which point the bushy tail flips up and curls forward, exposing the white hair. The tail is around 10 inches long.

(© gsagi / iStock)

(© gsagi / iStock)

In summer, the White-tail’s hair is reddish-brown and relatively short, with a thin, wiry texture. It dulls to grayish in winter, with long guard hairs and a thick undercoat to provide insulation. The hair of White-tailed Deer who live in northern regions has hollow shafts which fill with air. (There’s a unique subspecies of white-haired (not albino) White-tailed Deer living on protected grounds of the former Seneca Army Depot in Romulus, New York, the only ones in the world. Their future is in jeopardy. Read more about them.)

White-tailed Deer have excellent senses: Their vision is sharp, including superb peripheral vision — because their eyes are located at the sides of their head, they can see almost all the way around their body. Also, their eyes have more light-detecting cells than we humans have, which give them great night vision. Sharp as their vision is, smells and sounds carried in air currents can alert them to danger long before their eyes can detect it: Their sense of smell is their strongest sense — reportedly 10,000 times better than ours. And, their large, upright ears, 5 to 12 inches long, can capture the softest sounds.

White-tailed Deer have 32 teeth, but no front teeth in their upper jaw. Instead, a tough pad sits in their place. It’s used to help the lower front teeth hold food in place.

Deer skeleton (Jean-Georges Ferrié, Michel Coutureau and Cédric Beauval)

Deer skeleton (Popular Science Monthly, Vol. 4 / Wiki; PD)

Their legs are long and slender with powerful muscles — perfectly build to escape predators. The front legs provide swift turning and pivoting ability. The back legs are built for leaping and speed — they can jump 10 feet high or 30 feet forward in a single bound and gallop 35 miles per hour. They’re also great swimmers — up to 13 miles per hour. Their agility makes the deer a challenge for predators (for gardeners, too — if White-tailed Deer see something yummy inside a garden fence, well, over it they go.)

Deer feet are “cloven” hooves, meaning split into two toes, which bear the weight of the animal. They have two other toes located higher up on the leg. Called dewclaws, they’re similar in structure to the hooves, but smaller, and they don’t touch the ground, except when the deer runs, jumps or is on soft ground. The outer surface of the hoof, called the hoof wall or horn, is hard and similar to our fingernails.

Antlers

Male with partly grown antlers. (Larry Smith / Flickr; cc by 2.0)

 It’s commonly assumed that “antler” and “horn” are two names for the same thing, but there’s a difference. Antlers come in pairs, they’re branched and protrude from the front of the deer’s skull. As for horns, they also protrude from the front of the skull, but they’re permanent and don’t branch.

Antlers are grown each spring and are temporary. Growth begins as longer days trigger an increase in the male’s testosterone level. First thing, two bumps on his forehead, one a few inches above each eye, react to the hormone by forming a “bud” from which the antlers will grow. Called pedicle, they’re covered with skin and hair and made of spongy bone. (Male fawns begin to grow them at only a couple of months old.)

Within a month the first tine (or point) begins to form. A month later, a second tine starts forming. Antlers grow fast — up to 2 inches or more per week — and in about four months they’re fully developed.

Antlers

(Popular Science Monthly, Vol 9; / Wiki; PD)

Each antler has a main beam that first grows slightly in a backward direction, then reverses and curves forward and over the face. Each main beam holds from one to several un-branched tines. Antler width (or spread) for the White-tail is calculated by the greatest inside spread between the main beams. Spread may range anywhere from 3 to 25 inches. Antlers are usually symmetrical, but asymmetrical pairs also occur, with tines growing in every direction.

While antlers are growing they’re soft to the touch and covered in “velvet,” a skin tissue filled with a rich supply of blood vessels and nerves. (The top photo on this page shows velvet antlers.) By late summer, however, decreasing day length signals the testosterone level to drop and the blood supply turns off. The velvet, now starved of blood, dries up and falls off, often in just a day or two. Males rub their antlers against trees during this time, which clears off the velvet and, incidentally, polishes their antlers to a rich shine.

Males use their now-hardened antlers for combat displays of strength and dominance over one another during the breeding season. The sound of antlers colliding can often be heard over long distances and this sometimes attracts females in heat. After breeding season is over, antlers drop off, or “shed.” This leaves an open wound, but it covers over with skin. Come next spring, the process starts all over again.

Cast-off antlers are rarely found in nature. They’re rich in nutrients and other animals gnaw them right up. Interestingly, if the tissue that gives growth to antlers is surgically removed from a male’s head and grafted onto another part of his body, a tiny antler will grow there. (Oh, dear, scientists will try most anything!)

Antlers generally get bigger as animals grow older. Bucks at 1.5 years old average four tines, while at 3.5 years and older, they average 8 tines. After about 7.5 years the antler size declines. It seems like this would be a good way to judge an individual buck’s age. But, not so, say the experts — genes and injury influence antler growth, as do any nutritional deficiencies in calcium, protein, phosphorus or other vitamins.

So, what do the experts do? They check the teeth. It so happens that fawns have baby teeth, just like humans — they’re born with four and in a few months will grow baby incisors and premolars. At around 18 months the baby teeth will have been replaced with adult teeth, which are permanent. After that, amount of wear on the molars is used to establish the animal’s age — teeth lose about 1 millimeter of height above the gum line each year.

Four-chambered stomach

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Four-chambered stomach of deer (Pearson Scott Foresman / Wiki; CC)

White-tailed Deer are “ruminants,” a word taken derived from Latin for “to chew the cud.” There are about 150 other species of ruminants, including cattle, goats, sheep, antelope, camels and llamas.

White-tailed Deer are herbivores. Plants of various kinds are their only food once they’re weaned from their mothers. They have a stomach with four chambers specifically designed to undertake the tough demands of a high-cellulose diet.

The first two chambers are the rumen (ROO-men) and reticulum (ruh-TIC-u-lum). They perform the same function and are collectively called the reticulorumen (ruh-TIC-u-low-ROO-men). After food is partly chewed and swallowed, it passes back and forth in the reticulorumen, mixing with saliva and breaking down into solids and liquids. The solid material clumps together and is regurgitated. Deer slowly re-chew (ruminate) the material (the cud) to mix it with more saliva and break it down into smaller particles. Depending on how much fiber is in the food, they may spend several hours a day chewing their cud.

Once swallowed again, the cud passes through the reticulorumen into the omasum (oh-MAY-sum), where many of the mineral elements are absorbed into the blood stream. From there the mixture moves into the abomasum (AB-oh-MACE-um), which is equivalent to a human stomach, and from there into the small intestine. All four chambers contain huge populations of various bacteria and other microbes which break down and ferment the food material.

Behavior
White-tailed Deer, being prey animals, are shy and always on alert. They may be active to some extent at all times, but primarily move about in the hours near dawn and dusk, when they can’t be easily seen. They reduce their exposure to danger by leaving their cover only briefly — for instance, to quickly eat and then move back into hiding. During hunting season they may become completely nocturnal. During breeding season, roughly late-September through January, males shed some of their hyper-wariness and leave heavy cover to seek out mates. Hunting season is timed so hunters can take advantage of this.

White-tailed Deer live in social groups consisting of an adult female, her fawns and her yearling female offspring. They usually remain together until fall, at which time the yearling males separate from their mother and sisters as breeding season approaches. (If they don’t leave voluntarily, the females will drive them away.) All males are solitary during breeding season, but may live together in small groups the rest of the year.

White-tailed Deer rest in “deer beds,” which are oval depressions in leaves, soft dirt or grasses. The beds are always surrounded by shrubs and grasses to shield the deer from prying eyes and bad weather. They rarely bed in the same spot twice, a tactic that probably protects them from predators.

Communication
White-tailed Deer have several ways of communicating with each other. For example, males use their antlers to strip bark off small trees — this marks their territory. The mark is called a “rub.” They also make scrape lines in their territory by using their front hooves to expose bare ground.

They vocalize, too. Not a lot, but 13 different calls have been identified. One particular call is used by females to locate other members of their family group. Another is made by mothers to call their fawns. Still another announces when a female is ready to mate. Bucks, also, have several different calls. Listen to deer sounds.

Another way White-tailed Deer communicate is with scent glands. Glands are located between the two parts of each hoof, on the outside of each hind leg, on the inside of each hind leg at the hock, between the eyes and at the base of each antler. The deer leave a scent every time they rub trees or shrubs. Scents alert females when males are moving through their area during breeding season. Scents also let males know when challengers are in the area. The scent glands between the hooves emit a substance with an offensive odor, so with every step a White-tail takes, a scent is left on the ground. Scent also serves as a danger-alert: The deer stomp their feet when they’re alarmed, which leaves an excessive amount of scent as warning to others.

Whited-tailed bucks sparring. (Brian Sstansberry / Wiki ;cc by 3.0)

Whited-tailed bucks sparring. (Brian Stansberry / Wiki; cc by 3.0)

Reproduction
Breeding season seems to be timed to occur about 6.5 months prior to the best fawning period for a particular locale. Commonly called rutting season or “the rut” by hunters, it runs when females are in estrus and males have high testosterone levels, anywhere from late-September through January.

Males spar with each other to win the rank of top deer. The reward is first choice of females. Sparring consists of ramming into each other, clicking antlers, trying to push each other backward, kicking and flailing their legs.

A male will chase a female for several days prior to mating, then mate with her several times. He remains with her for several days more to keep other bucks away. When they part company, the buck will go on to mate with several other females before the breeding season ends. He won’t be involved with females again until the next mating season.

The gestation period is about 200 days. A healthy female might mate when she’s as young as 7 months old. Females usually give birth to only one fawn the first time. After that, they usually have twins or, sometimes, triplets. The fawns are born quickly, sometimes with the mother standing.

Newborns weigh 5 to 8 pounds and wear a reddish-brown coat with white spots. Their eyes are open and they can stand and walk within an hour or two. They nurse almost immediately. This first nursing provides a high-protein milk called colostrum, which contains an assortment of antibodies that will help the fawns resist disease until their own immune system is developed.

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Can you spot the fawn? (Dherman1145 / Flickr; CC )

A mother stays away from her fawns, hiding them in dense vegetation to protect them from predators. She returns only two or three times a day to nurse them. While they wait, fawns tuck their legs, head and neck into their body for maximum concealment. They lie completely motionless when a predator is nearby. Their coat is a perfect camouflage in the dappled sunlight striking a forest floor. Even if out in the open, it’s hard for predators to see them, and they can’t smell them, either: Fawns have no body odor and hold their urine and feces until their mother returns. When she does, she ingests whatever the fawns eliminate in order to remove any tell-tale odors.

Fawns munch on vegetation as early as a week or so old. At about one month, they start accompanying their mother. Should a predator approach a fawn, their mother will show herself and run off in another direction, hoping to lure it away. Fawns are playful and spend their time frolicking, nudging, jumping and boxing one another with their legs and feet. They’re weaned at 8 to 12 weeks. They’ll sport their distinctive white spots for 3 or 4 months, until their winter coat grows.

White-tailed doe and fawn

Doe and her fawn. (Larry Smith / Flickr; cc by 2.0)

The family stays together until the next spring when the mother leaves her fawns and returns to her favorite birthing area to breed. All of her female offspring will remain in the same general area as their mother throughout their lives. Males, on the other hand, leave their mother in the fall, or certainly by the next spring — if they don’t, the females will force them to leave. Males might have to travel long distances to find new territories.

Life span
Life expectancy is up to 10 years in the wild, but males usually live no more than 2 or 3 years and females 5 to 6 years. In captivity, White-tailed Deer can live up to 20 years.

Habitat
The perfect habitat for a White-tail is an area of one or two miles composed of a mixture of trees, shrubs, vines, flowering plants, grasses and miscellaneous other plants, such as fungi. Water, too, of course. That’s the ideal, but White-tailed Deer are highly adaptable and manage to survive, even thrive, in many different environments, including forests, farmland, brushy areas, even shrubby deserts and from sea level to mountain ranges.

In agricultural areas, White-tailed Deer stay within a forested area until evening, then move out to feed in the fields. On the Plains, which are wide-open and scantily dotted with areas of cover, White-tailed Deer travel along grassy gullies and draws that offer them some cover.

Some White-tailed Deer live year-round in swamps, which provide them with water, many species of trees that drop nuts or offer good wood for browsing, and soft bedding and cover for hiding. In some areas, during hunting season White-tailed Deer head for boggy swamp areas that are inaccessible to hunters.

In summer, White-tailed Deer like fields and meadows, and seek shade on hot days in deciduous and coniferous forests. In winter, the forests offer some protection from harsh weather.

All a White-tail needs for encouragement to become a city resident is a park or neighborhood with 20 acres or more of habitat offering them food, water, shelter and cover.

Food Sources
White-tailed Deer are herbivores and their diet is based on the plants available to them. In a forest, they might feed on undergrowth and fungi. In agricultural areas they eat such crops as corn and alfalfa, while in the city their diet might consist of shrubs, fruits, nuts, vegetables and flowering plants. Soft-stemmed, broad-leaved, flowering plants (forbs) are their favorites and, given a choice, they’ll pick these over most woody plants and grasses every time. That’s because forbs are more easily digested, providing their body with more available protein. In some tropical and subtropical areas, White-tailed Deer survive without eating any woody plants.

Predators
White-tailed Deer are very alert to everything going on around them. They’re agile and fast. They often enter streams and lakes to escape predators. But life is perilous, particularly for fawns. It’s estimated that the amount of fawns lost from all causes runs 40 to 50 percent. Predators of fawns and adult White-tailed Deer include coyotes, mountain lions, bobcats, wolves and wild dogs. Humans are the main predator of adults — hunters kill an estimated 6 million a year and injure about twice that number. In some states, hunters take up to 80 percent of the antlered deer each year. Motor vehicles annually kill almost two million more.

White-tailed Deer at a glance

Appearance: Tail: white on edge, underside; summer coat: reddish-brown; winter: grayish; fawns: white spots
Size: Height: 32-40 in; Length: 52-95 in.;  Weight: females: 90-100 lbs.; males: 150+ lbs. Lifespan: 10 yrs. in wild; 25 yrs. in captivity
Range/habitat: Across U.S.
Behavior: Shy, alert; active at dawn, dusk; scent glands mark trails, territory; sexes socialize only in breeding season; females form family groups, males may group together Foods: Herbivorous: twigs, leaves, grasses, fruits, vegetables, nuts, flowering plants
Cover: Tall grasses, forests, hedges, undergrowth, whatever is available
Reproduction: Breeding season Sept.-Jan. depending on locale; 200 day gestation; 2-3 fawns
Predators: Coyotes, bobcats, mountain lions, wolves, wild dogs, hunters, autos
Called: Male:buck; female: doe; young: fawn.
Scientific classification
Kingdom: Animalia
Phylum: Chordata
Class: Mammalia
Order: Artiodactyla (even-toes ungulates)
Suborder: Ruminantia (cud chewers)
Family: Cervidae
Genus: Odocoileus Species:
virginianus
 

*Top photo: White-tailed buck and doe. (Larry Smith / Flickr; cc by 2.0)

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