Abstract
We evaluated long-term (∼50-year) change in a bird community of an extensively forested region of the southern Appalachian mountains in North Carolina and Tennessee. A species accumulation curve for a 1996–1998 survey identified a core of 50 breeding species in upper elevations of the Unicoi Mountains. Since a 1944–1946 survey, dominant species have remained identical, no species have disappeared, and mean ranked abundance of both short and long-distance migrants has not changed. Permanent residents, however, had decreased in rank by the late 1990s. Three “new” disturbance-dependent species, American Crow (Corvus brachyrhynchos), Indigo Bunting (Passerina cyanea), and Song Sparrow (Melospiza melodia), expanded into interior forest along a recently constructed parkway. Largest apparent increases in ranked abundance of individual species occurred in eight Neotropical migrants that rely upon mature, forest-interior habitat, whereas largest apparent declines in ranked abundance occurred in land-use generalists, cavity nesters, and three other Neotropical migrants. Modifications to land-use were reasonable explanations for changes in most species. Little change in community structure, greater representation of many Neotropical migrants, and virtual absence of Brown-headed Cowbirds (Molothrus ater) suggest that this large, continuous forest retained and probably regained functional integrity for forest birds during the latter half of the twentieth century.
Using a Commercially Available Enzyme Immunoassay to Quantify Testosterone in Avian Plasma
