Experimental determination of the response of Golden-cheeked Warblers (<em>Setophaga chrysoparia</em>) to road construction noise

Authors: M. A. Lackey, M. L. Morrison, Z. G. Loman, B. A. Collier, R. N. Wilkins

Noise pollution can mask or distort bird songs, which can inhibit mating success, predator detection, and parental response to begging calls. We examined the impact of road construction noise on territory selection, reproductive success, and behavior of the federally endangered Golden-cheeked Warbler (Setophaga chrysoparia). To examine habituation and territory placement, we (1) used construction-noise playback to individual Golden-cheeked Warblers and evaluated occurrence of behavioral response as a function of distance from the roadway, and (2) established broadcast units that simulated construction noise to determine effects on territory selection. Among 88 surveys, six birds responded to construction-noise playback; all birds that responded were located ≥140 m from the road. We established three broadcast units per season in 2008 and 2009 to test for habituation. In each year, we placed broadcast units on the edges of randomly chosen territories identified during the previous field season. We found no significant difference in mean territory shifts for territories with and without broadcast units, and territory shifts showed no patterns in directionality or reproductive success. Our results suggest that birds located in the noisiest areas have habituated to construction noise, whereas those in the quietest areas have not habituated; however, the very low number of observed responses indicated that the majority of Golden-cheeked Warblers have habituated to road and construction noise.