Habitat Associations Between the Northern Flying Squirrel and Red Spruce

Abstract

Red spruce forests, one of the most critically endangered ecosystems in the United Statesprovides critical habitat for several endemic species or subspecies of the Appalachian Mountains, including the Virginia northern flying squirrel. Once listed as threatened under the Endangered Species Act, the Virginia northern flying squirrel was delisted in 2013. Managers are currently focusing their efforts on projects that increase the extent and connectivity of the squirrel’s habitat through red spruce restoration. At present, there is a paucity of available data to assess the implications of the silvicultural activities associated with red spruce restoration on the movement and occupancy of the Virginia northern flying squirrel. In order to inform management activities, I measured home range, fine-scale habitat use, and estimated detection and occupancy for northern flying squirrels across a gradient of red spruce stands in the Monongahela National Forest. I concluded that home ranges for northern flying squirrels within this region are comprised primarily of red spruce and that northern flying squirrels were selecting larger diameter trees compared to the nearest available neighbor. Additionally, I found that microhabitat characteristics alone did not sufficiently predict northern flying squirrel occupancy and that acoustic methods for surveying northern flying squirrels will require further refinement. Future research efforts should focus on a combination of landscape-level and microhabitat covariates to best predict occupancy of this species across the landscape. Future red spruce management should be approached with caution regarding the potential impact on northern flying squirrel habitat in the short-term. I recommended using spatially-explicit modeling to assess the long-term effects of proposed red spruce restoration projects on northern flying squirrel population demographics, dispersal, and metapopulation connectivity prior to the implementation of silvicultural treatments.