Damage to Structures
In general, deer do not damage structures. They occasionally run through and break fences and plate-glass windows.
Damage to Livestock and Pets
As herbivores, deer pose little threat to other animals. The feeding habits of deer may compete with livestock. Deer are involved in the maintenance of the virus that causes epizootic hemorrhagic disease and blue tongue in livestock. On occasion, deer attack dogs.
Damage to Landscapes
Deer may cause damage to a wide variety of row and forage crops, vegetables, fruit trees, nursery stock, ornamentals, and stacked hay. In addition to the immediate loss of the crop, feeding deer can affect the future yields. Ornamental trees and nursery stock may be permanently disfigured by browsing. High densities of deer may severely impact native plants and impair regeneration of some species.
Health and Safety Concerns
Deer-vehicle strikes are the biggest threat to the human safety that is posed by deer. In addition to the economic loss in damaged vehicles, 100 to 200 people in the US die each year along with thousands who are injured by hitting or avoiding deer (Figure 8). Exercise the following to reduce the chances and impacts of a deer-vehicle collision: drive cautiously, follow the speed limit, wear a seatbelt, observe deer-crossing signs, be extra vigilant during the fall mating season and spring dispersal period, anticipate that more deer may be present, and do not swerve to miss deer, as this frequently leads to injuries due to rollovers and collisions with other vehicles and objects.
Deer are susceptible to several diseases, but only a few are of concern to humans. Deer assist in the movement and development of ticks that carry Lyme disease, ehrlichiosis, and babesiosis. Deer can be reservoirs for bovine tuberculosis, which threatens the health of livestock and humans. On rare occasions, deer have attacked people.