The use of species distribution models (SDMs) to predict the spatial occurrence and abundance of species in relation to environmental predictors has been debated in terms of species’ ecology and biogeography. The predictive power of these models is well recognized for vertebrates, but has not yet been tested for invertebrates. In this study, we aim to assess the use of SDMs for predicting local abundances of invertebrates at a macroscale level. A maximum entropy algorithm was used to build SDMs based on occurrence records of 61 species of butterflies and bioclimatic information with a 30 arc second resolution. Predictions of habitat suitability were correlated with butterfly abundance data derived from independently conducted field surveys in order to check for a relationship between the predictions of the model and local abundances. Even though the model accurately described the current distributions of the species in the study area at a macroscale, the observed occurrences of the species (i.e. presence/absence) recorded by the field surveys differed significantly from the model’s predictions for the corresponding grid cells. Moreover, there was no correlation between observed abundance and the model’s predictions for most species of butterflies. We conclude that the spatial abundance of butterflies cannot be predicted from environmental suitability modelled at a resolution as large as in this study. Using the finest scale bioclimatic information currently available (i.e. 30 arc seconds) it is not adequate to predict species abundances as structural and ecological factors as well as climatic patterns acting at a smaller scale are key determinants of the occurrence and abundance of invertebrates. Therefore, future studies have to account for the role of the resolution in environmental predictors when assessments of spatial abundances via SDMs will be conducted., Katharina J. Filz, Thomas Schmitt, Jan O. Engler., and Obsahuje seznam literatury
Helminth parasites of wild and domestic felines pose a direct or potential threat to human health. Since helminths depend on multiple environmental factors that make their transmission possible, it is imperative to predict the areas where these parasites may complete the transmission to potential hosts. Bobcats, Lynx rufus (Schreberer), are the most abundant and widely-distributed wild felid species in North America. The increase of population densities of bobcats raises concerns about their importance as reservoirs of pathogens and parasites that may affect wildlife, domestic animals and humans. Our objective was to predict the potential presence of the tapeworm Taenia rileyi Loewen, 1929, the fluke Alaria marcianae (La Rue, 1917) and the roundworm Toxocara cati (Schrank, 1788) in southern Illinois. The empirical presence of these parasites in localities across the region was analysed in combination with a sampling bias layer (i.e. bobcat presence) and with environmental data: layers of water, soil, land cover, human density and climate variables in MAXENT to create maps of potential presence for these three species in an area of 46 436 km2. All climatic variables were low contributors (0.0-2.0% contribution to model creation) whereas land cover surfaced as an important variable for the presence of A. marcianae (7.6%) and T. cati (6.3%); human density (4.8%) was of secondary importance for T. rileyi. Variables of importance likely represent habitat requirements necessary for the completion of parasite life cycles. Larger areas of potential presence were found for the feline specialist T. rileyi (85%) while potential presence was less likely for A. marcianae (73%), a parasite that requires multiple aquatic intermediate hosts. This study provides information to wildlife biologists and health officials regarding the potential impacts of growing bobcat populations in combination with complex and changing environmental factors.