Ground beetles on islands: on the effects of habitat and dispersal

Neutral theory focuses on random dispersal and species equivalence, and challenges views on the ecological importance of life history traits and habitat properties in explaining community assembly and the spatial distribution of species. Ground beetles are a popular model taxon to test predictions of contrasting macroecological theories. Here we investigate the effects of habitat properties and life history on the occurrence and community structure of 71 carabid beetle species inhabiting 15 lake islands in NE Poland. Island properties, particularly area and habitat quality, were positively linked to the occurrences of 42% of the species and correlated with species richness and beta-diversity. Life history traits (hibernation type, dispersal ability and average abundances) significantly influenced species occurrences. Thus, site and species properties influence the spatial distribution of species and macroecological patterns on islands.