Robert Loeb, Penn State, rxl5@psu.edu (Presenter)
James Helton, Lipscomb University, jmhelton@mail.lipscomb.edu
Samuel King, , kingsr@mail.lipscomb.edu


In 1980 white-tailed deer (Odocoileus virginianus) and in 2000 American beaver (Castor canadensis) migrated to the Radnor Lake State Natural Area, Nashville, TN and formed resident populations. In the five Natural Area forest communities, the total tree stems per ha decreased from 1974 to 2008. From 1994 to 2008, O. virginianus over browsing decimated the seedling population of all species. Except for the ravine forest that had extensive tree losses, the total for stems per ha for saplings was less than the total stems per ha for trees. In contrast, deer over browsing has caused an increase for Acer saccharum across the five communities when comparing 1974 to 2008. The eight beavers have progressively converted the streamside forests into marshy bottomlands. The beavers have two large lodges and have constructed an extensive network of canals and check dams. The beavers also have been foraging around the entire circumference of the 34 ha lake on almost every species of tree, regardless of stem diameter. However, the foraging was found to stop at a roadway and dramatically decreased beyond the trails that surround the lake indicating human placed developments act as boundaries for beaver foraging.