Selection of nest trees by southern flying squirrels (Sciuridae : Glaucomys volans) in Arkansas

Natural nest-site selection was investigated in 50 radiocollared southern f lying squirrels Glaucomys volans during spring and summer, 1994-1996, in th e Ouachita National Forest of Arkansas. Squirrels nested in 226 trees in a variety of habitats at five study areas. Contrary to previous reports descr ibing southern flying squirrels as habitat generalists, in this study squir rels showed selection in both the habitat and tree type in which nests were placed. Where it was available, mature pine-hardwood forest was selected f or nesting. Young (< 15 years old) and immature (15-40 years old) pine plan tations and harvested areas were avoided as nesting habitats. At harvested study areas, squirrels nested in protected riparian mature forest strips (g reenbelt) along, and 10-20 m either side of, intermittent creeks and in adj acent mature forests. Squirrels constructed only outside nests in pine tree s. In mature pine-hardwood forest, pines were used for outside nests more f requently than hardwoods; in greenbelt habitat, pines and hardwoods were ch osen equally for outside nests. Both outside and cavity nests were found in hardwoods; standing dead trees (snags) contained only cavity nests. Snags were selected over hardwoods for cavity nesting in both mature pine-hardwoo d forest and greenbelt habitat. All hardwood species and all decay classes of snags were used for diurnal nesting in greater frequency than expected. Considering both cavity and outside nest-site selection, pines were used le ss than expected. Results suggest that mature forests are optimal flying sq uirrel nesting habitats and should be retained adjacent to harvested areas to provide resources to squirrels abandoning stands after disturbance. With in harvested areas, nesting habitat can be substantially improved through t he retention of overstory hardwoods and snags, as well as protection of mat ure forest strips along drainages.