Effects of Road Construction Noise on the Endangered Golden-Cheeked Warbler

Noise pollution can mask or distort bird songs, which can inhibit mating success, predator detection, and parental response to begging calls. Using an impact assessment design, we examined the potential influence of road construction and road noise on territory placement, reproductive success, and density of the federally endangered golden-cheeked warbler (Dendroica chrysoparia) at 3 sites: adjacent to road construction, adjacent to road-noise only, and a control with no noise or activity. Although not statistically significant, reproductive success was about 20% higher and stable at road-noise-only sites relative to other treatments. Warbler density was similar among sites (construction = 0.305 birds/ha; road-noise = 0.357 birds/ha; and control = 0.328 birds/ha). Average distance from road was similar for territories with paired adults (road-noise = 291 m [SE = 26], construction = 263 m [SE = 19]) and those with successful pairs (road-noise = 292 m [SE = 27]), construction = 243 m [SE = 21]). Overall noise levels were low: ambient noise was similar in the construction and road-noise-only sites ((X) over bar = 32 dB) and showed little auditory difference from the control ((X) over bar = 28 dB). Our results indicate that construction activities and road-noise did not appear to impact territory placement, reproductive success, or local densities of golden-cheeked warblers under the treatment regime we studied. (C) 2011 The Wildlife Society.