Researchers believe that our native forests evolved with deer densities of 10 per square mile. At the turn of the century, white-tailed deer were nearly extirpated from many of the eastern states through uncontrolled market hunting. State agencies have had great success in revitalizing the deer population. They were not prepared, however, for the great resurgence in numbers, especially in suburban areas. Statewide, Pennsylvania’s deer population now exceeds 20 per forested square mile, which is considered the appropriate level to maintain healthy forest ecosystems. In many parts of southeastern Pennsylvania, populations exceed 100 deer per square mile. These levels have dire consequences for present and future forest resources.
High deer populations dramatically impact the survival of native flora by over browsing tree and shrub regeneration and consuming herbaceous plants. It is believed that more than 100 species of native wildflowers have become extirpated as a result of deer browse. The resulting lack of cover, food, and structural diversity within our forests has undoubtedly reduced populations of small mammal and bird species.
Although there are effective techniques (tree shelters, fencing, repellents) for deterring deer access to vegetation, they are costly and simply shift the problem to neighboring properties. Numerous studies have proven that removing deer through controlled hunts is the most practical and effective means for addressing this problem. The rules governing Natural Lands Trust’s hunting program place an emphasis on removing does from the population. Doe harvesting brings populations to tolerable levels more quickly than a random removal strategy.
The goal of controlling deer populations has many benefits. Not only will we be able to retain species (both plant and animal) on our nature preserves, but also we will be able to expand and enhance forest resources through natural regeneration and afforestation programs.