Birds of the forest interior dominate the landscape in the Big South Fork. Edge species also find some habitat to suit their needs, but birds of open country are largely excluded from the park, and the degree of exclusion increased each year as the park’s forests mature and their open areas diminish.
Besides having general characteristics determined by habitat, the bird communities of the Big South Fork are quantitatively distinct during the various seasons of the year. Observers can detect more birds per hour afield in the Big south Fork during the spring and early summer that any of the other seasons. As summer proceeds into fall, birdsong decreases and many breeding species begin to migrate south, the detectability and density of birds in the Big south Fork diminish. During the late winter the detectability and density reaches it lowest point, however, by late March an influx of early migrants swells the numbers and the increase continues until peak numbers are once again recorded in May and June.
An important feature of the bird community in Big South Fork is the large component of Neotropical migrants breeding within or migrating through the park. Almost 50% of breeding species and most transients in the park belong to this group of New World birds that nest mainly in the temperate or boreal zones of the northern hemisphere during summer and then spend the winter in the tropics of Central and/or south America.
Undeveloped parks like Big South Fork provide breeding habitat and migration stopover points for many such species and are therefore of considerable importance to their survival.
