Connectivity compensates for low habitat quality and small patch size in the butterflyCupido minimus

Abstract

AbstractHabitat size, habitat isolation and habitat quality are regarded as the main determinants of butterfly occurrence in fragmented landscapes. To analyze the relationship between the occurrence of the butterflyCupido minimusand these factors, patch occupancy of the immature stages in patches of its host plantAnthyllisvulnerariawas studied in the nature reserve Hohe Wann in Bavaria (Germany). In 2001 and 2002, 82A.vulnerariapatches were surveyed for the presence ofC. minimus larvae.The occurrence was largely affected by the size of the food plant patches. In a habitat model that uses multiple logistic regression, the type of management and habitat connectivity are further determinants of species distribution. Internal and temporal validation demonstrate the stability and robustness of the developed habitat models. Additionally, it was proved that the colonization rate ofC. minimuswas significantly influenced by the distance to the next occupiedAnthyllispatch. Concerning long‐term survival of (meta‐) populations in fragmented landscapes, the results show that lower habitat quality may be compensated by higher connectivity between host plant patches.