Animal Damage Control: WHITE-TAILED DEER

Description and Social Values

The white-tailed deer (Odocoileus virginianus) is the most abundant member of the deer family (family Cervidae) in North America. Their long legs make them well-adapted for escape from predators through a variety of habitats. Keen hearing, good eyesight and an acute sense of smell provide additional protection from danger.

Adult white-tailed bucks (males) are 3' to 3.5' tall at the shoulder and typically weigh 125 to 200 lbs. Does (females) are generally smaller and lighter than the males. Deer are red-brown during summer and grow brown-grey winter coats each fall. Their most conspicuous feature is their tail, which they raise during flight to expose its white underside. Fawns, deer less than one year old, are typically born weighing four to eight lbs. and have red-brown hair covered with numerous white spots. They lose these spots as they grow their first winter coat. Bucks, but not does, grow antlers annually, which are deer-raa slideused as weapons and in social displays, particularly in relation to reproduction.

White-tailed deer are an important component of our wildlife heritage and are avidly sought by hunters, photographers and nature observers. Big-game hunters spend millions of hours and dollars in pursuit of deer each year, providing a significant economic boost to many rural communities. Farmers, nursery operators and orchardists - the people who are most often negatively impacted by deer - may tolerate serious crop damage because they enjoy deer and consider them aesthetically valuable.

Although generally thought of as wildlife of forest and field, deer have become a sight in many suburban and urban areas. Many deer are killed each year on highways, resulting in substantial damage to vehicles, potential human injury and millions of dollars in insurance claims.

Life History

White-tailed deer breed from mid-September through late February, with peak breeding occurring during mid-November. Fawns are born in the spring after 200 days gestation. Does (and occasionally fawns) usually produce a single fawn during their first pregnancy. Twins are typically born in subsequent years in areas with adequate food resources. Triplets may also occur.

Bucks begin antler development in spring and antler size depends on both age and nutrition. The growing bone is covered with hairy skin called velvet which nourishes the antler. The bone hardens and the velvet is rubbed off in the fall. Bucks shed their antlers each winter.

Deer consume a variety of vegetative foods and show considerable preferences for individual plants and plant parts. Commonly-eaten foods include grasses, fruits, nuts, herbs and mushrooms, as well as leaves and stems from trees and shrubs. Deer concentrate their feeding on woody materials when herbaceous plants are unavailable.

Description of Damage

Deer damage to agricultural crops and forest regeneration is a serious and widespread problem. Deer cause economic losses when males remove bark and branches from trees and shrubs during their fall and winter antler-rubbing activities. They may occasionally trample crops, but the primary form of damage consists of feeding on selected plant parts. Deer readily browse forage, grain and vegetable crops, fruit and nut trees, ornamental woody plants and flowers. Without control measures, damage levels may severely reduce crop yields on many sites. In forested areas, excessive deer numbers can reduce or eliminate regeneration of important lumber-producing tree species.

Deer browsing damage is readily distinguished from that caused by rabbits or rodents. Deer leave a ragged, broken end on browsed branches, compared to the cleanly-nipped terminal left by other wildlife. Deer browsing on agricultural crops and landscape plants is most frequent and severe when natural food sources are limited, particularly during winter and early spring. However, damage occurs year-round on many sites.

Legal Status

Deer are classified as game animals, and can be killed only during legal hunting seasons by persons holding a valid big game license. Hunting laws vary from state to state. Check with local authorities when getting a license. Whenever possible, deer populations should be controlled via regulated hunting during the appropriate seasons.

Deer Management Methods

Population Control. Animal reduction in deer populations via sport hunting is an effective way to reduce deer damage. Deer have the potential to double their population about every 2.5 years if no mortality takes place. Buck-only harvests are incapable of reducing or stabilizing deer numbers. Where legally possible, landowners suffering damage should require hunters to harvest sufficient does, as harvesting of females is essential to reduce deer numbers and damage.

Physical DC143CBarriers. Fencing, wire cages and plastic netting are the most cost-effective deer damage controls in many circumstances. Woven wire fences 8 feet high are very effective barriers to deer, but are cost effective for only the most valuable crops and ornamental plantings. High tensile electric fence designs have been developed which are less costly and almost as effective as tall woven wire fences. When prorated over their expected life spans, fences are often more cost effective than repellent spray programs. Individual cages and plastic netting are effective controls for small plantings or individual plants. Physical barriers are the only effective means of preventing antler-rubbing damage.

Chemical Repellents. A variety of commercial deer repellents are labeled for use in New England. For example, BGR "Deer-Away", "Hinder", and products containing the fungicide thiram have been shown to be most effective in several studies. A variety of home remedies have been reported to effectively repel deer. However, these products may be less cost effective than commercial repellents when their labor requirements are considered in the total application cost. In addition, their effectiveness is often highly variable and their long-term impact on the environment has not been studied.

Repellents are most effective when applied prior to the occurrence of deer damage, and in situations where damage is expected to be light to moderate. Repellents are considered cost effective on small acreage when approximately three sprays are needed annually. However, sprays may need to be reapplied every three to four weeks during the growing season to cover new plant growth. Spray costs can be reduced by tank mixing repellents with other crop protectants. Repellents should be applied when temperatures are between 40 and 80oF on days when precipitation is not expected. Consult the label for application and compatibility information.

Scare Devices. A variety of frightening devices including lights, whistles, loud noises and scarecrows have been used to prevent deer damage. However, deer quickly habituate to these devices and resume foraging. In addition, many of the devices are expensive, have high maintenance requirements and may be dangerous to humans.

Cultural Practices. Deer damage may be reduced by planting less preferred plant species. Considerable interest also exists in planting adjacent areas with preferred food (diversionary feeding). However, little information is available on the use or success of supplemental plantings.

Health Risks

A variety of diseases and parasites may be carried by deer which have potential deleterious effects on humans and domesticated animals. These include anthrax, various arboviruses, foot and mouth disease, and tuberculosis. Lyme disease is currently the major health concern associated with deer. Deer serve as one of several potential hosts for the deer tick (Ixodes dammini) which transmits the Lyme disease bacterium. Lyme disease has reached epidemic proportions in Connecticut, Rhode Island and in coastal areas of Massachusetts. Individuals who are active outdoors and in particular, hunters who handle and transport deer should examine themselves and their clothing frequently for deer ticks. Persons bitten by a tick should consult their doctor.

Rabies in white-tailed deer has rarely been reported. Spillover cases of raccoon rabies into deer have been reported. A deer observed behaving abnormally should be treated with caution. Hunters should wear rubber gloves when dressing game animals and all wild game should be thoroughly cooked before consumption.

Further information on preventing Lyme disease and rabies is available from your state or county health department.

Deer damage photos

More deer information: Deer Damage and Control

Rose Hiskes, University of Connecticut
This article is adapted from a fact sheet by Michael J. Fargione and Paul D. Curtis, Dept. of Natural Resources, Cornell University, Ithaca, NY.
photos by Richard A. Ashley, University of Connecticut

The information in this material is for educational purposes. The recommendations contained are based on the best available knowledge at the time of printing.Any reference to commercial products, trade or brand names is for information only, and no endorsement or approval is intended. The Cooperative Extension systemdoes not guarantee or warrant the standard of any products referenced or imply approval of the product to the exclusion of others which also may be available.All agrochemicals/pesticides listed are registered for suggested uses in accordance with federal and Connecticut state laws and regulation as of the date of printing.If the information does not agree with current labeling, follow the label instructions. The label is the law.Warning! Agrochemicals/pesticides are dangerous. Read and follow all instructions and safety precautions on labels. Carefully handle and store agrochemicals/pesticides in originally labeled containers out of the reach of children, pets and livestock. Dispose of empty containers immediately in a safe manner and place. Contact the Connecticut Department of Environmental Protection for current regulations. The user of this information assumes all risks for personal injury or property damage.Issued in furtherance of Cooperative Extension work, Acts of May 8 and June 30, 1914, in cooperation with the U.S. Department of Agriculture, Kirklyn M. Kerr, Director,Cooperative Extension system, University of Connecticut, Storrs. The Connecticut Cooperative Extension System is an equal opportunity employer.