Quality of anthropogenic habitats for Golden-winged Warblers in central Pennsylvania

Abstract

Populations of Golden-winged Warblers (Vermivora chrysoptera) are declining dramatically in eastern North America. Success of conservation efforts will rely largely upon identification and management of suitable anthropogenic habitats (e.g., harvested forest and utility rights-of-way [ROWs]). We assessed habitat quality among three habitat types in central Pennsylvania by comparing population density, nesting success, and productivity among 1-ha patch clearcuts (clearcut area), a 60-m-wide utility ROW (wide ROW), and a 20-m-wide utility ROW (narrow ROW) in 2002 and 2003. Golden-winged Warblers did not use any portion of the narrow ROW that occurred outside the clearcut area. Density (territories/ha) did not differ either year (all P ≥ 0.20) between used sectors of the clearcut area (0.47, 0.50) and the wide ROW (0.71, 0.79). Overall nesting success (successful nests/total nests) was not independent (P = 0.012) of habitat type (58% in the clearcut area, 15% in the wide ROW). Overall productivity (young fledged/nesting territory) was greater (P = 0.026) in the clearcut area (2.38) than in the wide ROW (0.57). Our study raises important questions about the suitability of utility ROWs for Golden-winged Warblers.