White-tailed deer (Odocoileus virginianus) are perhaps the most abundant large game mammal in the United States, ranging in size from 50-200 lbs. While some adult males (bucks) can grow up to 3.5 ft tall at shoulder height 
and weigh up to 300 lbs, an average buck in New York weighs around 150 lbs. Females (does) are typically smaller and average around 100 pounds. Deer under the age of 1 yr (fawns) are 4-8 lbs at birth, with good resources, fawns as young as 6 months can begin breeding.
White-tailed deer are herbivorous browsers, feeding on virtually every part of many different plant species. Foraging mostly in the dawn and dusk hours, deer will eat approximately 2 to 7 lbs per 100 lbs of body weight each day. Agricultural and horticultural practices created a constant supply of high quality food resources for deer. Extirpation of natural predators, such as wolves (Canis lupus) and cougars (Felis concolor), lowered natural mortality rates have all led to deer problems.
Agricultural Damage
Wildlife damage to U.S. agriculture is reported to result in the loss of $4.5 billion of crops annually. White-tailed deer are responsible for the majority of the damage. White-tailed deer damage was responsible for 58% of field crop losses and 33% of losses to vegetables, fruits, and nuts. Causing nearly $1 billion in farm, garden and timber damage, federal officials say. One deer can consume a ton and a half of greenery a year.
A survey revealed that deer are responsible for 79% of wildlife-related agricultural damage, resulting in a yield loss of $7.86-15.73 (Inflation Adjusted) million per year. Deer damage occurs in the form of feeding, buck rubs, and/or trampling of crops and is characterized by a torn, jagged appearance on vegetation or a square, ragged break on woody material. Most browse damage occurs from the ground level up to a height of approximately 6 feet. Residual damage may occur from the trampling or matting down of vegetation as deer travel through crop fields or bed down to rest. Buck rub damage, which occurs as males shed the velvet from their antlers each autumn, can be identified as scarred saplings, broken limbs, bruised bark, and/or exposed wood. Rubs usually are located on the trunks of trees up to 3 ft above ground level.
Often farmers forgo cultivation of preferred crops due to excessive deer damage. Normal crop rotation is also hindered, and farmers may be forced to abandon a field completely. Crops that experience the most damage from deer include grains, corn, soybeans, pumpkins , tomatoes, and lettuce.
Health Issues from Deer
Increases in tick-borne illnesses are often attributed to deer overabundance because deer serve as hosts for many tick species, particularly the Black Legged (deer) ticks (Ixodes scapularis), the carrier of several human diseases. The most common disease associated with deer ticks is Lyme, which is caused by the bacteria, Borrelia burgdorferi, and categorized by a recurrent arthritis and an annular rash. Other tick-borne illnesses include babesiosis, human granulocytic ehrlichiosis, and human monocytic ehrlichiosis, which all cause flu-like symptoms. These diseases are all treatable, with early detection improving treatment results. Deer herds can become infected with other diseases as well that don’t effect humans like EHD. Diseases similar to EHD are found in domestic animals like horses, cattle, and sheep. Deer can also spread and livestock ailments.
Deer-Vehicle Collisions
The burgeoning Whitetail deer population throughout the suburban areas of Western N.Y. is resulting in an increasing number of conflicts between deer and people. Between July 1, 2010 and June 30, 2011, there were over 1 million deer-related collisions in the U.S. with the accidents killing more than 100 people annually and causing more than $1 billion in deer caused damage. Deer are most active seasonally from mid-September through November during the peak of the breeding season (rut). Activity increases shortly after sunrise and between sunset and midnight. Deer crossings commonly occur where roads cause fragmentation of intact forest or separate forest from agricultural lands. Heightened driver awareness in these areas during peak activity periods can help reduce deer-vehicle collisions. Obeying the speed limit and using high-beam headlights can also increase driver reaction time.
Ecological Impacts
No native vertebrate species in the eastern United States has a more direct effect on habitat integrity than the white-tailed deer. In many states deer populations continue to rise well beyond historical norms. In many areas of the country deer have changed the composition and structure of forests by preferentially feeding on select plant species. As deer increase in abundance, browsing pressure reaches a tipping point, where individual plants cannot recover from the damage. Plant abundance and diversity decline rapidly, leading to several cascading negative impacts on the ecosystem.
By feeding on or damaging tree seedlings and saplings, an overabundant deer population prevents forests from naturally regenerating. The shrub and herbaceous layers also disappear, leaving a barren woodlot of trees rather than a healthy, functioning forest (Figure 2). With significantly less vegetation than a healthy forest, other ecosystem processes are impacted. The lack of leaves falling to the ground each autumn results in poor quality soils, increased erosion, and a lack of nutrients required for plant growth and reproduction. These changes, combined with the openness of the forest floor, make room for nonnative plant species to colonize, further compromising the health of native habitats.
Habitat changes caused by overbrowsing are also detrimental to native birds, small mammals, and invertebrates. Indirect effects on wildlife have been reported as well, such as widespread declines of North American songbird populations. Many birds nest in native vegetation on or close to the forest floor, while others rely on the constant supply of insects within the leaf litter and in vegetation to feed themselves and their young. The absence of nuts and berries in overbrowsed forests also leads to a decrease in food supply for small mammals and migratory birds, making it difficult for them to survive at critical times during the year.
Property Damage from Deer
While deer numbers might not exceed biological carrying capacity, in some places they have exceeded human tolerance for deer-related conflicts. In many rural and suburban areas, residents complain that deer damage home landscaping. The homeowners and landscapers struggle to keep deer away from their plantings, which are prime deer fodder because they are fattened with ample fertilizer and water. Home gardens and landscaping are expensive in both financial terms and in the homeowners time and efforts in maintenance. Even when natural foods abound in local area, deer are often attracted to the rich succulent plants of the backyard landscape. Natural foods are limited by the natural pH and nutrients of the soil and are in competition with neighboring plants for sunlight. In the backyard, trees, plants, and gardens are usually enhanced. In addition, the woodlot openings created by our home sites provide additional sunlight to our domestic plantings. When natural food supplies are limited either seasonally or by over use by deer, the backyard becomes a magnet for deer. Therefore while many people view deer as a nuisance.