Can brief marking campaigns provide reliable dispersal estimates? A Nickerl’s Fritillary (<i>Melitaea aurelia</i>, Lepidoptera: Nymphalidae) case study

Abstract

Functions expressing dispersal probability decays with increasing distance are widely used in studies of animal movements. The inverse power function (IPF) exhibits the property of self-similarity, and hence should perform robustly against variation in marking efforts, allowing comparisons across studies. We investigated this function property using dispersal data of Nickerl’s fritillary (Melitaea aurelia), a little studied checkerspot butterfly which is currently expanding in Central Europe. During mark-recapture in South Moravia, Czech Republic, a single researcher worked for the entire flight period in 2005, while in 2006 five researchers worked for just 5 days. Slopes of the fitted functions did not differ between the two seasons, illustrating the robustness of the function and suggesting the possibility to obtain reliable dispersal estimates even from brief marking campaigns. For both years, it was predicted that approximately one individual per one thousand would cross 10 km distance, the maximum distance separating the most isolated colonies in the region.