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Predicting potential habitat across a landscape for rare species is extremely challenging. However, partitioned Mahalanobis D² methods avoid pitfalls commonly encountered when surveying rare species by using data collected only at known species locations. Minimum habitat requirements are then determined by examining a principal components analysis to find consistent habitat characteristics across known locations. We used partitioned D² methods to examine minimum habitat requirements of Indiana bats (Myotis sodalis) in the Champlain Valley of Vermont and New York, USA, across 7 spatial scales and map potential habitat for the species throughout the same area. We radiotracked 24 female Indiana bats to their roost trees and across their nighttime foraging areas to collect habitat characteristics at 7 spatial scales: 1) roost trees, 2) 0.1-ha circular plots surrounding the roost trees, 3) home ranges, and 4-7) 0.5-km, 1-km, 2-km, and 3-km buffers surrounding the roost tree. Roost trees (n = 50) typically were tall, dead, large-diameter trees with exfoliating bark, located at low elevations and close to water. Trees surrounding roosts typically were smaller in diameter and shorter in height, but they had greater soundness than the roost trees. We documented 14 home ranges in areas of diverse, patchy land cover types that were close to water with east-facing aspects. Across all landscape extents, area of forest within roost-tree buffers and the aspect across those buffers were the most consistent features. Predictive maps indicated that suitable habitat ranged from 4.7-8.1% of the area examined within the Champlain Valley. These habitat models further understanding of Indiana bat summer habitat by indicating minimum habitat characteristics at multiple scales and can be used to aid management decisions by highlighting potential habitat. Nonetheless, information on juvenile production and recruitment is lacking; therefore, assessments of Indiana bat habitat quality in the region are still incomplete. [ABSTRACT FROM AUTHOR]

Understanding how changes in landscape properties influence common species is relevant as it allows us to identify patterns that could be shared with co-distributed species that occupy the same landscapes. The northeastern United States (NE-USA: New York state and the six states of New England) is heavily urbanized and affected by continuous and prolonged anthropogenic activities, leading to intensive landscape fragmentation and loss of natural forests. Here, we used a landscape genetics approach to explore the genetic diversity and structure of the Southern Flying Squirrel, Glaucomys volans , and how resulting patterns may be related to landscape fragmentation and forest loss in the NE-USA. To study G. volans genetic variation and population structure, we amplified and genotyped 10 microsatellites loci from DNA extracted from tissue samples stored in biological collections and natural history museums. To assess the influence of landscape on gene flow and connectivity, we used two genetic distances metrics–proportion of shared alleles and codominant marker, and tested two landscape cost models approaches–least cost path and isolation by resistance. We identified three genetic clusters, with low but significant genetic differentiation between them. We did not find correlation between geographic distance and genetic variation in these populations. According to landscape models, land cover and elevation were the best predictors of genetic connectivity of G. volans , although were poorly related to genetic distances. Our results suggest that gene flow occurs between G. volans populations across the NE-USA despite the changed landscape configuration, implying potential dispersal of individuals between patches. Nonetheless, individuals from the eastern periphery of the distribution may have been temporarily isolated in the past due to historical deforestation. The current regeneration of hardwood forests represents a positive outlook for the genetic integrity of G. volans populations in the NE-USA because more possibilities for corridors and patches of habitable forests emerge. These changes would improve the connectivity of the species in the region and avoid possible local extinction events. [ABSTRACT FROM AUTHOR]