Analysing and modelling range changes in UK butterflies

摘要

We investigate the distributions of three species of satyrid butterfly (P. aegeria, A. hyperantus and P. tithonus) that are currently expanding in the UK. These species were chosen because they have broadly similar ecologies and dispersal abilities but differ in their habitat requirements and thus in the availability of suitable breeding habitat. Since the 1940s, range margins of these species have shifted northwards in the UK in agreement with climatic changes. Rates of expansion differ among the species in the order P. tithonus > A hyperantus > P. aegeria, mirroring patterns of habitat availability. We show that climate is important in determining their distributions at a European scale. At a UK scale, both climate suitability and habitat availability are significantly and positively related to butterfly distributions, but there is evidence that P. aegeria and A. hyperantus, the two species with the most restricted habitat requirements, are lagging behind current climates. All three species will have the potential to extend their ranges northwards under predicted future climate warming, but the distribution of habitat is likely to impact on their ability to track climate change. Many UK species have more restricted habitat requirements and are more sedentary than the species considered here; they are likely to have much greater problems tracking changing climates.