Damage caused by deer

Deer as Pests- Problems caused by deer

Deer can become serious pests. Most problems occur when the population of deer becomes too high. The main problems that deer can cause are as follows:

Damage to the Ground Vegetation in woodlands

Deer can reduce the biological diversity of woodlands. In healthy woodlands the ground is covered with a thick blanket of ground vegetation, and there is a dense under storey of bushes and shrubs. This provides a valuable habitat for many woodland species of plants, insects and mammals. Many woodland species rely on this dense layer of vegetation below the tree canopy for a home. If the number of deer in woodland is to high, then the ground vegetation, and the lower parts of bushes and low trees become overgrazed and eventually disappear. The species that live in this habitat disappear as well, and the diversity of the woodland is reduced.

Damage to agricultural crops

Deer can be a serious pest of agricultural crops. Fields cultivated for crops provide an easily accessible source of food for deer, and one they will readily take advantage of. The temptation is especially great during the winter months or the early spring, when natural supplies of food are at their lowest. For example Roe Deer are a common sight on cereal crops where they will feed on the fresh shoots of wheat. If the population of deer is low then the problem is not normally too serious, and the amount of damage caused will be low, but in areas with high populations of deer considerable damage can be caused. One example of deer causing a problem can be seen in the Chinese Water Deer in Cambridgeshire. During the winter months these will leave the reed beds and marshes where they live and move onto neighbouring fields to feed on root crops. They can congregate in large numbers and cause a significant loss of crops.

Road Traffic Accidents

Deer and traffic do not mix well. Deer cause thousands of road traffic accidents each year. A small number of people are killed each year in road traffic collisions with deer and many more injured. Millions of pounds worth of damage is caused to cars and property because of deer related accidents. The majority of accidents occur when deer stray onto carriageways at night, as this is when deer are most active . Most damage and injuries are caused not by drivers running into a deer, modern cars are strong enough to withstand impact with even a large deer, but as a result of drivers swerving to avoid deer and then crashing into something else. Drivers who swerve into the path of an oncoming car to avoid a deer cause some of the worst accidents.

Damage to trees

Deer can cause much damage to trees. Different species of deer cause damage in different ways, but most will strip bark from around the trunk of trees as high as they can reach. This lowers the value of the wood to foresters when the trees are logged. The damage caused to the tree makes it grow less well and in some cases can even kill it. In areas where there are high numbers of deer are a high proportion of the trees found in a woodland can become damaged. More about the damage caused by deer to trees is given opposite.


© Mark Walker 2005