The establishment and distribution of feral wild boar (Sus scrofa) in England

Until recently, geographic isolation has protected Britain from the widespread increases in wild boar populations seen elsewhere in Europe, but following the development of wild boar farming in the 1980s a number of escapes and releases have occurred, resulting in the re-establishment of the species in the wild in England. The present study monitored the establishment and presence of wild boar in England by collating reports of escapes or releases and ground-truthing evidence of animals in the wild. This data is used to give an up-to-date indication of the distribution of the species in England. In the twenty years from 1989/90 to 2008/9 an average of one to two escape/release incidents occurred each year, with individual incidents involving from one to more than 50 individuals. These have resulted in the establishment of at least four distinct populations, the largest of which probably has a pre-breeding population in excess of 200 animals. None of the escapes or releases involving five or fewer individuals is believed to have led to establishment of a population. Based on the availability of woodland, there is potential for a total population in England of around 30,000 – 40,000 animals. However, future development of local populations is likely to be constrained over much of the country because of low woodland cover and culling pressure, and it is likely to take many years for a population of this size to develop, if at all.