ADULT MOVEMENTS BETWEEN POPULATIONS IN THE SPECIALIST BUTTERFLY PROCLOSSIANA-EUNOMIA (LEPIDOPTERA, NYMPHALIDAE)

1. The structure of local populations of a monophagous butterfly, the bog fritillary Proclossiana eunomia, was studied in a complex of suitable habitat patches separated by spruce plantations or fertilized pasture. 2. An unexpected high level of adult movements between habitat patches was detected by a mark-release-recapture technique. Local populations were connected by adult movements across unsuitable habitats, leading to a metapopulation structure. 3. This evidence of the metapopulation structure of a specialist butterfly challenges the supposed relationship between habitat specialization and closed, isolated populations. 4. Males and females of P.eunomia exhibited different spatial behaviours; females were more likely to emigrate and dispersed further than males. These differences in spatial behaviour are related to the mating system.