Patterns of mammalian species richness and habitat associations in Pennsylvania

Landscape variables were employed as indices of habitat heterogeneity, fragmentation, and human influence on the environment to characterize constituent units of a 635 km(2) grid covering the state of Pennsylvania. Species richness was determined by overlaying the distributions of all 60 terrestrial mammalian species found within the state. All landscape variables investigated were correlated with species richness. Areas with high topographic variation and low road density had the highest species richness. Species sensitive to habitat fragmentation were also associated with large forest patches and low road density. These landscape variables may be useful in identifying areas that are important for the conservation of these species. Associations between species distributions and landscape variables were substantiated by published habitat associations. Species with extremely limited distributions were not associated with landscape variables and represent special cases for conservation planners. Rare species, as defined by their limited geographical distribution, were not associated with areas of high species richness (hotspots). The utility of species richness hotspots for conservation planning is disputable. Hotspots of species richness were associated with large forest patches and low load density. (C) 2001 Elsevier Science Ltd. All rights reserved.