Year: 1981
Type: article
Abstract: In recent years there has been much interest in the southward range expansion of the Whip-poor-will (Caprimulgis vociferus).Baker and Peake (1966) made several listening counts for Whip-poor-wills and Chuck-will'swidows (C.carolinensis) around Athens, Georgia, and determined that the Whip-poor-will was extending its summer range southward to include the lower Piedmont of Georgia.Allen (1979) found the Whip-poor-will to be fairly abundant in the suburban areas of Clarke County although it was greatly outnumbered by the Chuck-will's_widow.He reported substantial clustering in the local distribution of the Whip-poor-will, so that in some places it had actually replaced the Chuck-will's_widow.Prior to this, the Whip-poor-will had been described as "an uncommon transient south of the mountain counties" (Burleigh 1958).Odum (1943) reported the Whippoor-will as not having substantially changed its distribution in the previous 35 years.By 1968, however, the Whip-poor-will was listed as a locally common summer resident around Athens, Georgia (Tramer 1968).The Chuck-will's_widow has always been a common summer resident in this area.Because caprimulgids are often heard but seldom seen, listening counts made at periodic intervals along secondary and dirt roads are a logical way to determine their abundance.Brauner (1952) related dawn and dusk activity of Poor-wills (Phalaenoptilus nuttallii) to light intensity, and related duration of the active period of this species to several factors, especially moon phase.Mengel and Jenkinson (1971) also mentioned the importance of moonlight relative to caprimulgid calling activity.Harper (1938) found that on moonless nights, Chuck-will's_widow's singing appeared to be limited to brief periods at dusk and daybreak.On moonlit evenings, however, the birds continued to sing indefinitely.Baker and Peake (1966) mentioned the negative effect of wind on calling.These and other studies, however, have varied in both techniques and results so that the information is of little comparative value (Dillenbeck 1967, Nunley 1960).The purpose of this study was to determine the relative abundance of Chuck-will's_widows and Whip-poor-wills in Clarke County, Georgia, from a series of call counts, and to correlate different environmental factors with calling activity.363
Author: Robert J. Cooper
Language: English
Topic: Avian ecology and behavior
Subfield: Ecology
Field: Environmental Science
Domain: Physical Sciences
Open Access status: green
OpenAlex ID: W2517287119