HABITAT DISTRIBUTION MODELS: ARE MUTUALIST DISTRIBUTIONS GOOD PREDICTORS OF THEIR ASSOCIATES?

Abstract

Because of time and resource limitations, extensive studies of distributions at fine resolutions over entire landscapes are not viable, and distribution maps must be delineated using static habitat models. In cases where short life cycles and time limitations prevent the collection of detailed abundance and distributional data to generate habitat models for target species, one potential alternative is to use models of the abundance or occurrence of closely associated species (e.g., prey, host plant, mutualist) to predict the abundance or occurrence of the target species. We present a predictive model for the habitat of the butterfly Plebejus argus in scrubland in a protected area in southern Spain (Donana National Park), based on the distribution of its mutualist ant Lasius niger, field habitat data, and topographical variables from a digital elevation model. The frequency of nests of L. niger was by far the major predictor of P. argus abundance and presence–absence. In turn, high L. niger frequency was a...