Our Animals - White-Tail Deer

Our Animals > White-Tail Deer

The white-tailed deer (Odocoileus virginianus), also known as the Virginia deer, or simply as the whitetail, is a medium-sized deer native to the United States (all but five of the states), Canada, Mexico, Central America, and in South America as far south as Peru. It has also been introduced to New Zealand and some countries in Europe, such as Finland and the Czech Republic.

The species is most common east of the Rocky Mountains, and is absent from much of the western United States, including Nevada, Utah, California, Hawaii, and Alaska (though its close relatives, the mule deer and black-tailed deer Odocoileus hemionus, can be found there). It does, however, survive in aspen parklands and deciduous river bottomlands within the central and northern Great Plains, and in mixed deciduous riparian corridors, river valley bottomlands, and lower foothills of the northern Rocky Mountain regions from Wyoming to southeastern British Columbia. The conversion of land adjacent to the northern Rockies into agriculture use and partial clear-cutting of coniferous trees (resulting in widespread deciduous vegetation) has been favorable to the white-tailed deer and has pushed its distribution to as far north as Prince George, British Columbia. Populations of deer around the Great Lakes have also expanded their range northwards, due to conversion of land to agricultural uses favoring more deciduous vegetation, and local caribou and moose populations. The westernmost population of the species, known as the Columbian white-tailed deer, once was widespread in the mixed forests along the Willamette and Cowlitz River valleys of western Oregon and southwestern Washington, but today its numbers have been considerably reduced, and it is classified as near-threatened. The white-tailed deer is well-suited for its environment.

Description

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, which it shows as a signal of alarm by raising the tail during escape.

The North American male deer (also known as a buck) usually weighs from 130 to 300 pounds (60 to 130 kg) but, in rare cases, bucks in excess of 375 pounds (159 kg) have been recorded. The record-sized White-tailed Deer weighed just over 500 pounds and was found in Minnesota.[4] The female (doe) usually weighs from 90 to 200 pounds (40 to 90 kg). Length ranges from 62 to 87 inches (160 to 220 cm), including the tail, and the shoulder height is 32 to 40 inches (80 to 100 cm).[5] White-tailed deer from the tropics tend to be much smaller than temperate populations, averaging 77–110 pounds (35–50 kg).

Female with characteristic tail coloringMales re-grow their antlers every year. About 1 in 10,000 females also have antlers, although this is usually associated with hermaphroditism.[7] Bucks without branching antlers are often termed "spiked bucks". The spikes can be quite long or very short. Research in Texas has shown that the length and branching of antlers is genetic and can be influenced by diet. Healthy deer in some areas that are well fed can have eight point branching antlers as yearlings (one and a half years old). The number of points, the length or thickness of the antlers are a general indication of age but cannot be relied upon for positive aging. A better indication of age is the length of the snout and the color of the coat, with older deer tending to have longer snouts and grayer coats. Many say that deer that have spiked antlers should be culled from the population as they are not as large or as hardy as bucks with branching antlers, and never will be, but this is only true in areas where the deer's complete nutritional needs are met, which is only a small percentage of their range. Spike deer are different from "button bucks" or "nubbin' bucks", that are male fawns and are generally about six to nine months of age during their first winter. They have skin covered nobs on their heads. They can have bony protrusions up to a half inch in length, but that is very rare, and they are not the same as spikes.

Antlers begin to grow in late spring, covered with a highly vascularised tissue known as velvet. Bucks either have a typical or non-typical antler arrangement. Typical antlers are symmetrical and the points grow straight up off the main beam. Non-typical antlers are asymmetrical and the points may project at any angle from the main beam. These descriptions are not the only limitations for typical and a typical antler arrangement. The Boone and Crockett or Pope & Young scoring systems also define relative degrees of typicality and atypicality by procedures to measure what proportion of the antlers are asymmetrical. Therefore, bucks with only slight asymmetry will often be scored as "typical". A buck's inside spread can be anywhere from 3–25 in (8–64 cm). Bucks shed their antlers when all females have been bred, from late December to February.

There is a population of white-tailed deer in the state of New York that is entirely white (except for areas like their noses and toes) - not albino - in color. The former Seneca Army Depot in Romulus, New York, has the largest known concentration of white deer. Strong conservation efforts have allowed white deer to thrive within the confines of the depot.

The white-tailed deer is a ruminant, which means it has a four-chambered stomach. Each chamber has a different and specific function that allows the deer to quickly eat a variety of different food, digesting it at a later time in a safe area of cover. The Whitetail stomach hosts a complex set of bacteria that change as the deer's diet changes through the seasons. If the bacteria necessary for digestion of a particular food (e.g. hay) are absent it will not be digested.

Behavior and reproduction

These bucks were pursuing a pair of does across the Loxahatchee River in Florida— the does lost them by entering a Mangrove thicket too dense for the buck's antlersFemales enter estrus, colloquially called the rut, in the fall, normally in late October or early November, triggered mainly by declining photoperiod. Sexual maturation of females depends on population density. Females can mature in their first year, although this is unusual and would occur only at very low population levels. Most females mature at 1–2 years of age. Most are not able to reproduce until six months after they mature.

Males compete for the opportunity of breeding females. Sparring among males determines a dominance hierarchy. Bucks will attempt to copulate with as many females as possible, losing physical condition since they rarely eat or rest during the rut. The general geographical trend is for the rut to be shorter in duration at increased latitude. There are many factors as to how intense the "rutting season" will be. Air temperature is one major factor of this intensity. Any time the temperature rises above 40 degrees Fahrenheit, the males will do much less traveling looking for females, or they will be subject to overheating or dehydrating. Another factor for the strength in rutting activity is competition. If there are numerous males in a particular area, then they will compete more for the females. If there are fewer males or more females, then the selection process will not need to be as competitive.

Females give birth to 1–3 spotted young, known as fawns, in mid to late spring, generally in May or June. Fawns lose their spots during the first summer and will weigh from 44 to 77 pounds (20 to 35 kg) by the first winter. Male fawns tend to be slightly larger and heavier than females.

White-tailed deer communicate in many different ways using sounds, scent, body language, and marking. 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. Does also bleat. Grunting produces a low, guttural sound that will attract the attention of any other deer in the area. Both does and bucks snort, a sound that often signals danger. As well as snorting, bucks also grunt at a pitch that gets lower with maturity. Bucks are unique in their grunt-snort-wheeze pattern that often shows aggression and hostility. Another way white-tailed deer communicate is with their white tail. When a white-tail deer is spooked it will raise its tail to warn the other deer in the area that can see them.

Male white-tailed deer (Florida Keys subspecies) before breeding season with antlers still in velvet.White-tailed deer possess many glands that allow them to produce scents, some of which are so potent they can be detected by the human nose. Four major glands are the pre-orbital, forehead, tarsal, and metatarsal glands. It was originally thought that secretions from the pre-orbital glands (in front of the eye) were rubbed on tree branches; recent research suggests this is not so. It has been found that scent from the forehead or sudoriferous glands (found on the head, between the antlers and eyes) is used to deposit scent on branches that overhang "scrapes" (areas scraped by the deer's front hooves prior to rub-urination). The tarsal glands are found on the upper inside of the hock (middle joint) on each hind leg. Scent is deposited from these glands when deer walk through and rub against vegetation. These scrapes are used by bucks as a sort of "sign-post" by which bucks know which other bucks are in the area, and to let does know that a buck is regularly passing through the area—for breeding purposes. The scent from the metatarsal glands, found on the outside of each hind leg, between the ankle and hooves, may be used as an alarm scent.

Throughout the year deer will rub-urinate, a process during which a deer squats while urinating so that urine will run down the insides of the deer's legs, over the tarsal glands, and onto the hair covering these glands. Bucks rub-urinate more frequently during the breeding season. Secretions from the tarsal gland mix with the urine and bacteria to produce a strong smelling odor. During the breeding season does release hormones and pheromones that tell bucks that a doe is in heat and able to breed. Bucks also rub trees and shrubs with their antlers and head during the breeding season, possibly transferring scent from the forehead glands to the tree, leaving a scent other deer can detect.

Sign-post marking (scrapes and rubs) are a very obvious way that white-tailed deer communicate. Although bucks do most of the marking, does visit these locations often. To make a rub, a buck will use its antlers to strip the bark off of small diameter trees, helping to mark his territory and polish his antlers. To mark areas they regularly pass through bucks will make scrapes. Often occurring in patterns known as scrape lines, scrapes are areas where a buck has used its front hooves to expose bare earth. They often rub-urinate into these scrapes, which are often found under twigs that have been marked with scent from the forehead glands.