Influence of hilltop vegetation type on an African butterfly assemblage and its conservation

For South African butterflies that congregate on hill summits, thevegetation type that clothes hills has a major influence on behaviour andspecies assemblages. Congregation of individuals occurred on grass-covered hillsin a grassland matrix, while little congregation occurred on hills covered with undisturbed natural forest, nor on those with closely packed, mixed,plantation trees. Hill-summit congregation was not prevented by smalldifferences in hilltop grassland vegetation type, nor by low densities of thealien plant Eucalyptus grandis. This study demonstrates theimportance of taking into account the interplay of topography, vegetation typeand architecture when planning for conservation.