The decline of the roe deer (Capreolus capreolus L.) in the New Forest, Hampshire

The New Forest is an area of some 375 km2 in Hampshire, southern England. Of the 267 km2 administered by the Forestry Commission, some two-thirds consists of open heathland with varying expanses of bog, grassland, woodland and scrub. Domestic cattle and ponies range freely across this area. The remaining area, some 8640 ha., is enclosed for commercial timber production. Five species of deer occur within the Forest: fallow, roe, red, sika and muntjac. The Commission carries out an annual census count of each deer species except muntjac; the census counts for roe suggested a steady decline in the population in each of the Forest's beats over 1972-88. The purpose of this study has been to investigate this decline, both to determine its cause and as a study of the biology of a declining ungulate population. An initial assessment of the census data suggested the decline was real, and not merely an artifact of the data collection, and was associated with the areas of enclosed woodland rather than the Open Forest. Both the annual changes in roe numbers over the period of decline, and variation in the present density of roe across the Forest were found to be strongly associated with the vegetation of the enclosed commercial woodlands. Changes in roe numbers over 1976-85 were consistently correlated with the decline in prethicket stage conifer stands. Roe density across 12 study sites in the Forest was also correlated positively with the local abundance of bramble, holly and ivy, and negatively with that of bracken and Molinia, relationships reflected in associations between roe density and the mature woodland stands at those sites which tend to bear such vegetation. Associations were also found between yearly changes in roe numbers over 1972-88 and several climatic factors, but the association with vegetation was dominant.