Introduced species, such as muntjac and Chinese water deer, seem to be doing very well within the county and both species have increased in numbers and range over the last few years. Drive along any of the roads through Thetford Forest on a summer evening and you will see several dozen muntjac grazing on the verge during the course of your journey. These small, dog-sized, deer are surprisingly solid and any collision with a motorcar is likely to be damaging to both parties.
Research has demonstrated that at high densities, deer populations damage deciduous woodland by preventing natural regeneration and by removing much of the ground flora. This, in turn, reduces opportunities for other wildlife and is thought to be one of the reasons for the declines seen in a number of woodland bird species. Experiments using deer fences to exclude deer from small blocks within woodland show just how pronounced the impact of deer grazing can be.
There may be good ecological and commercial reasons for the numbers of deer to be controlled and control through shooting has been an important component of forest management within the county for many decades. As with any control programme, it is important to know how many individuals there are in an area in order that a suitable level of control can be established. In the case of deer this can be something of a problem. Deer populations are not easy to monitor, in part because of their secretive nature, but also because populations may range over large areas. Traditional methods of monitoring mammals, such as recording field signs like tracks and droppings, are not always readily applicable to deer and require a high degree of skill on the part of the observer. Having said this, efforts are being made to build up a more complete picture of the number of deer in our region and various organisations are working together, through the Deer Initiative, to improve our understanding of these wonderful animals.