The Heaths of Dorset and their Conservation

Abstract

2. The need for home-grown timber, and the scarcity of suitable sites for new plantations. 3. The southward trend of the British human population. By a geographical accident the two largest areas of lowland heath in Britain-those on the Tertiary sands of the London and Hampshire Basins-are adjacent to two very large expanding centres of population (London, and the Poole-Bournemouth conurbation). Building pressure is therefore particularly strong: heathland is required both for sites for houses and gardens and for the extraction of gravel and sand used for building houses and roads. The work described in this paper was undertaken on behalf of the Nature Conservancy during 1953-60, when the author was Regional Officer for south-west England, was living in the area and was responsible for the management of heathland nature reserves in Dorset and for other official conservation work in the district. It was undertaken to obtain a scientific basis for administrative action; to answer such questions as: (i) How much heathland remains in Dorset? (ii) Which areas should be preserved? (iii) How large must a heathland nature reserve be if it is to support viable populations of certain species which it is designed to protect? (iv) To what extent can such species survive changes in land use of siUrrounding land? (v) What reserve manangement is necessary to maintain certain habitats and populations of certain species? The writer was therefore forced to take a superficial but comprehensive view of a welldefined habitat which once coyered about 150 sq. miles (389 sq. km) and is in the process of rapid change. In this paper the data have been arranged so as (i) to describe the changes in area of the heathland habitat and its fragmentation during the past century and a half, (ii) to describe the situation as it exists today in terms of land use (including the extent of grazing and burning) and of the distribution of indicator species, (iii) to forecast the fate of the existing flora and fauna in the light of observations made on their adaptations to changes in land use so far, and (iv) to discuss some of the conservation and ecological implications of the work described.