Influence of elevation on Southern Flying Squirrel (Glaucomys volans) relative abundance in Eastern Tennessee

Abstract

Southern flying squirrels (SFS) are arboreal, nocturnal rodents often associated with mast-producing trees such as American Beech (Fagus grandifolia), oaks (Quercus spp.), and hickories (Carya spp.). These trees provide key resources such as food and den sites within the SFS distribution. While SFS are widespread in Tennessee, the mountains of Eastern Tennessee provide unique habitat types not typically found in their range. As elevation increases the tree community gradually transitions into forests more characteristic of more northern latitudes, and at the highest elevations Red Spruce (Picea rubens) and Fraser Fir (Abies fraseri) dominate. These relict boreal forests represent refugia for northern species such as the Carolina Northern Flying Squirrel (CNFS, Glaucomys sabrinus coloratus). While typically isolated, SFS may overlap and compete with CNFS at the highest elevations. The objective of this study is to address the influences of elevation on relative abundances of SFS. Three survey methods (live traps, camera traps, and acoustic detectors) were deployed at low-, middle-, and high-elevation sites; and captured individuals, pictures taken, and acoustic recordings were combined to determine relative abundance of SFS. Research is ongoing, however relative abundances of SFS were highest in middle-elevation forests. High-elevation forests may be less suitable for SFS which could result in lower relative abundances. Conversely, increased abundances of SFS at higher elevations may have detrimental effects on CNFS exacerbating the decline of this federally endangered subspecies.