| dc.description.abstract | Many taxa exhibit geographic variation in acoustic signals, which can lead to reproductive isolation and divergence among populations. Geographic variation in the acoustic signals of wood warblers is well-documented, and may be related to habitat characteristics, geographic isolation, and cultural drift. Furthermore, many wood warblers sing two song types that may be driven by inter- and intra-sexual selection. The golden-cheeked warbler (Setophaga chrysoparia; hereafter warbler) is a federally endangered Neotropical wood warbler that nests exclusively in Central Texas. Previous studies have indicated that golden-cheeked warblers use a two-category song system similar to other wood warbler species, and suggested that first category (“A”) and second category (“B”) songs exhibit different patterns of variation. Using warbler songs recorded in 2012, 2017, and 2018 (n = 171 individuals), I examined geographic variation in A and B song characteristics across the species’ breeding range. I used frequency, time, and structure related song metrics to quantify and compare patterns of geographic variation in and between song types. A songs were more similar in form and less variable than B songs, supporting the idea that first and second category songs of wood warblers are driven by inter- and intra-sexual selection, respectively. I found different patterns of geographic variation in A and B songs and hypothesized that variation in A songs may be related to habitat characteristics, and variation in B songs may be related to geographic isolation and cultural drift. The results of my study further our understanding of the characteristics and variation of wood warbler song and song categories, and could be used in conjunction with other data (e.g., genetic) to help inform conservation planning for the golden-cheeked warbler. | en |
