Woodland management and butterfly diversity.

Abstract

Woodland provides a diverse range of habitats for British butterflies. Nearly three-quarters of Britain's resident species regularly breed in woodland, and about one-third are found exclusively or primarily in woods through much of their British range (although some are also found in more open habitats in western Britain and in Continental Europe). The true woodland species include Leptidea sinapis (wood white), Quercusia quercus (purple hairstreak), Satyrium w-album (white-letter hairstreak), S. pruni (black hairstreak), Boloria selene (small pearl-bordered fritillary), B. euphrosyne (pearl-bordered fritillary), Argynnis adippe (high brown fritillary), A. paphia (silver-washed fritillary), Mellicta athalia (heath fritillary), Ladoga camilla (white admiral), Apatura iris (purple emperor), Nymphalis polychloros (large tortoiseshell) and Pararge aegeria (speckled wood). Three of these are listed as Red Data Book species: N. polychloros is classified as endangered and probably now occurs only as an occasional migrant to Britain, while A. adippe and M. athalia are classified as vulnerable (Shirt, 1987) and are both protected under the 1981 Wildlife and Countryside Act. Five others are classed as scarce species in Britain (Nature Conservancy Council, 1989) and all but P. aegeria and L. camilla have undergone major range contractions in the past 100 years (Heath, Pollard and Thomas, 1984). Apart from these true woodland species, many typically grassland species will use rides or large glades within a wood. For the purposes of this review we will concentrate on those species found exclusively or primarily in woodland although most of the principles of management will benefit other butterflies as well as a wide variety of other insects.