Predictive habitat models derived from nest-box occupancy for the endangered Carolina northern flying squirrel in the southern Appalachians

W. Mark Ford; A.M. Evans; Richard H. Odom; Jane L. Rodrigue; C.A. Kelly; Nicole Abaid; Corinne A. Diggins; Doug Newcomb

doi:10.3354/esr00662

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Predictive habitat models derived from nest-box occupancy for the endangered Carolina northern flying squirrel in the southern Appalachians

W. Mark Ford·A.M. Evans·Richard H. Odom·Jane L. Rodrigue·C.A. Kelly·Nicole Abaid·Corinne A. Diggins·Doug Newcomb

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Abstract

In the southern Appalachians, artificial nest-boxes are used to survey for the endangered Carolina northern flying squirrel (CNFS; Glaucomys sabrinus coloratus ), a disjunct subspecies associated with high elevation (>1385 m) forests. Using environmental parameters diagnostic of squirrel habitat, we created 35 a priori occupancy models in the program PRESENCE for boxes surveyed in western North Carolina, 1996-2011. Our best approximating model showed CNFS denning associated with sheltered landforms and montane conifers, primarily red spruce Picea rubens . As sheltering decreased, decreasing distance to conifers was important. Area with a high probability (>0.5) of occupancy was distributed over 18662 ha of habitat, mostly across 10 mountain ranges. Because nest-box surveys underrepresented areas >1750 m and CNFS forage in conifers, we combined areas of high occupancy with conifer GIS coverages to create an additional distribution model of likely habitat. Regionally, above 1385 m, we determined that 31795 ha could be occupied by CNFS. Known occupied patches ranged from

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Endangered Species Research Article

Source-reported bounding extent: 34.995648624137246° to 37.285370946434895° latitude; -84.7466335932305° to -78.94333487363758° longitude. This indicates report coverage, not an exact sampling location. View area on OpenStreetMap.

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W. Mark Ford, A.M. Evans, Richard H. Odom, Jane L. Rodrigue, C.A. Kelly, Nicole Abaid, Corinne A. Diggins, Doug Newcomb. 2016. Predictive habitat models derived from nest-box occupancy for the endangered Carolina northern flying squirrel in the southern Appalachians. https://doi.org/10.3354/esr00662

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