The influence of pheasant releasing and associated management on farmland hedgerows and birds in England.

Abstract

Hedgerows are an integral part of the farmed landscape and are important habitats for many birds and other wildlife. Game managers recognize the importance of hedgerows for gamebirds, both in the nesting season for wild birds and as dispersal routes from woodland release pens for reared pheasants in late summer. Conservationists are interested in the potential impacts of pheasant releasing on wildlife and habitats. The aim of this study was to assess the impact of gamebird management on hedgerow structure and the density and connectedness of hedgerows at the landscape level by comparing sites with and without gamebird releasing. We surveyed 150 sites in southern and eastern England: 97 were on pheasant shoots while the others were on farms where there had been no pheasant releasing for at least 25 years. Using a combination of field survey, satellite imagery and GIS software, we determined hedgerow abundance and their structural characteristics. We also measured the extent of hedgerow connectedness. We found that the hedgerow structure was similar on farms with and without game shoots. However, hedgebanks were between 17% and 36% wider on game estates. Game estates also had between 10% and 65% more hedgerow per square kilometre than farms with no game shoot. We found no strong evidence that game management influenced bird numbers associated with individual hedgerows. We conclude that structural characteristics of hedgerows on sites with pheasant releasing do not differ from hedgerows on farms where there is no pheasant releasing undertaken. The tendency for wider hedgebanks and greater hedgerow abundance on game estates is likely due to the recognition of game estate managers of the value of hedgerows as habitats for gamebirds. The results of this study need to be considered within the context of other studies which have highlighted the potential negative effects of large pheasant releases on hedgerow vegetation.