Many people living in urban areas are seldom fortunate enough to see a deer, so it often comes as a surprise to learn that for every thirty people in the UK there is one deer. It comes as an even bigger surprise to be told that in many parts of the country deer are a significant pest.
The problem is that deer have a formidable appetite and they are not too discerning about what they eat, even when food is plentiful; in the winter, when food is scarce, they will eat almost anything that grows. This tendency to eat anything and everything constantly brings them into conflict with the foresters who look after our woods and forests.
You would expect the bark of a tree was not a meal to get excited about but to a deer it is a gastronomic delight. For a large, well established tree it is not the end of the world to lose a little bark but to a young sapling it might well be.
You can imagine tree bark as the skin of the tree and its main purpose is to protect the phloem layer beneath. Imagine the phloem as the blood of the tree which distributes food produced by the leaves to the rest of the tree. When the bark gets damaged then almost certainly the phloem will be damaged and the flow of food will be diminished. The rule of thumb is that the loss of 25% of the bark will not be too detrimental but 50% of the bark removed will put the tree at risk and anything over 75% removed will most likely result in the death of the tree.
An even worse problem is deer eating young saplings and in parts of the Caledonian Forest in Scotland the very existence of the forest is being put at risk by booming deer populations. Ordinarily a forest regenerates itself because seeds falling from the established trees germinate and grow into trees themselves to take the place of those that die of old age. Not so when there is an abundance of deer because they chew off all the tender young saplings and the worry is that when the parent trees die there will not be a new generation to take their place.
To combat the problem there is a wonderful charity called “Trees for Life” who are doing everything they can to ensure the continued existence of the forests without being too unkind to the deer!
Next week we will look at the types of deer you are likely to see in the UK even if you live in built-up areas. In preparation for that you might like to try the 3 quizzes on British mammals that are listed on our Nature Quizzes page.