Summary

Recent studies on butterflies have documented apparent evolutionary changes in dis-persal rate in response to climate change and habitat change. These studies often assume a trade-off between dispersal rate (or flight capacity) and reproduction, which is the rule in wing-dimorphic species but might not occur equally in wing-monomorphic species such as butterflies. 2. To investigate the relationship between dispersal rate and fecundity in the Glanville fritillary butterfly Melitaea cinxia we recorded lifetime individual movements, matings, ovipositions, and maximal life span in a large (32 26 m) population cage in the field. Experimental material was obtained from 20 newly established and 20 old local popu-lations within a large metapopulation in the Åland Islands in Finland