Introduction

This chapter reviews current knowledge and provides previously unpublished data on habitat selection and requirements of the otter (Lutra lutra) in Britain. Such information is evaluated in an attempt to provide a basis for habitat management aimed at otter conservation, and to expose areas where further research is needed.

Since the 1950s the otter has declined in many countries in Europe, including Britain (Foster–Turley et al., 1990). In response to this, the British Joint Nature Conservation Committee, following the European Community ‘Habitats Directive’ (Council Directive 92/43/EEC, 1992), laid down a strategy for otter conservation: ‘To maintain existing populations, encourage natural recolonisation, and effectively safeguard viable populations of otters and their habitats throughout their natural range in the United Kingdom’ (Anon., 1997). This implies an obligation to conserve those aspects of countryside that are important components of otter habitat. It is these components that the present review attempts to identify.

In principle, conservation management should be directed at environmental factors that limit numbers of the target species. In the case of the otter many of these factors are to be found in the almost linear habitat of the species, following banks and shores. However, although limiting factors should be a primary concern, there are also other aspects of the habitat that are attractive to otters (shown as ‘habitat preferences’), but which do not necessarily affect their numbers. Such aspects of habitat could, at least potentially, affect otter numbers at other times and in the absence of any other limiting factors.