Conservation status of the federally endangered Golden-cheeked Warbler
Authors: Texas A&M IRNR
The Golden-cheeked Warbler (Setophaga chrysoparia; hereafter warbler), a small, insectivorous, migratory songbird that breeds exclusively in mixed oak-juniper (Quercus-Juniperus) woodland of central Texas (Pulich 1976, Ladd and Gass 1999), was emergency listed in 1990 as federally endangered (USFWS 1990). At the time of its listing, research conducted on a small number of study sites located in the eastern portion of the warbler’s breeding range suggested that there was ~1,270 mi2 of potential warbler habitat in Texas supporting 13,800 warbler territories (Wahl et al. 1990; USFWS 1992). The USFWS (USFWS 1992) then developed warbler recovery criteria under the notion that there were few warblers existing in spatially structured populations across small, disjunct patches of warbler habitat. After ~25 years of research, recent and comprehensive studies indicate that there is ~5 times more warbler breeding habitat (~6,480 mi2) and that there are ~19 times more warblers (263,339 males; 95% CI = 223,927–302,620) than assumed at the time of the emergency listing decision (Collier et al. 2012, Mathewson et al. 2012). In addition, molecular work suggests there is no genetic basis for managing warblers as separate population entities (Lindsay et al. 2008). Collectively, these studies indicate that recovery criteria were based on a fundamental misunderstanding of the existing abundance and population structure of the species, and a re-examination of the warbler’s federally endangered listing status is strongly warranted by the USFWS.
Texas A&M IRNR. 2015. Conservation Status of the Federally Endangered Golden-cheeked Warbler. Unpublished Research Summary. Texas A&M Institute of Renewable Natural Resources, College Station, Texas, USA. Available at http://irnr.tamu.edu/publications/research-reports/.