Marginality: scale determined processes and the conservation of the British butterfly fauna

Current butterfly conservation efforts in the UK emphasize rarity, focusing on those species that are undergoing the most rapid declines. Most species, however, have been described as marginal, which applies to environmental and landscape factors that decrease the probability of population survival and persistence. Marginality involves temporal as well as spatial issues, with habitats, resources, and limiting conditions at any particular geographic location differing over time. These issues are discussed, along with the importance of these processes, to identify the key issues that need to be addressed to maintain the butterfly fauna in the midst of a changing landscape. The marginality issues are examined in terms of conservation efforts and the need to establish research priorities.