The American Ornithologists’ Union (1998) currently recognizes Yellow Warbler as a taxon containing 3 groups: Yellow Warbler (aestiva group) breeding in most of the continental United States, Canada and western Mexico; Golden Warbler, resident in south Florida, the Caribbean and the northern coast of South America and Mangrove Warbler resident on the coast of Middle America and South America to Peru and western Venezuela and a vagrant in Texas. Yellow Warblers of the aestiva group winter primarily along the coasts of north and central Mexico, then through Middle America and north and central South America east of the Andes (Howell and Webb 1995, Pyle 1997, Lowther et al. 1999, Lockwood and Freeman 2004).
Ranges and species limits among these 3 groups apparently need better definition before their status can be definitely established. The status of the 38 or more subspecies recognized within the 3 groups certainly needs extensive further study (Pyle 1997, Lowther et al. 1999).
DISTRIBUTION. During the 1987-1992 field work seasons of the TBBA project, observers did not find any confirmed breeding of Yellow Warblers in this state, but found 3 probable records in latilong-quads 26098-D4, 27098-F2 and 30101-A5. Observers also found 29 possible records fairly widely scattered. Lockwood and Freeman (2004) describe Yellow Warbler as a former rare summer resident along the Rio Grande River in the Trans-Pecos, on the Edwards Plateau and in the Panhandle. In Oklahoma atlasers found 3 confirmed breeding sites including one along the Red River just east of the Texas Panhandle (Kuhnert 2004).
SEASONAL OCCURRENCE. Yellow Warblers are common to abundant migrants throughout the state, particularly in the fall. Migrants are present from early April to late May and late July to mid-October. Breeding formerly occurred in Texas from early May to late July, based on egg dates from May 17 to July 13 and young in the nest from June to July 24. The species is rare in winter in the lower Rio Grande River valley (Oberholser 1974, Lockwood and Freeman 2004). The breeding season in Oklahoma is April to June (Kuhnert 2004); in Arizona, more comparable to western Texas, most breeding occurs from May through July (Wise-Gervais 2005).
BREEDING HABITAT. In Arizona, 86% of breeding evidence was found in riparian habitats dominated by cottonwood and willow, extending from desert habitats containing mesquite and salt cedar up to foothill-montane sycamore habitats (Wise-Gervais 2005). In western riparian areas, surrounded by desert or grassland habitats, territories may be as small as 0.16 ha (0.4 acre). The nest, a strongly constructed cup of interwoven milkweed fibers, hemp, grasses and plant down, is placed in an upright fork or crotch of a tree or in a brier tangle, usually 1-2.5 m (3-8 ft) above ground. The nest is lined with a felted mat of plant down, hair and fine grasses (Harrison 1979).
In this cup the female usually lays 4-5 (range 3-6) smooth, grayish, bluish or greenish white eggs, speckled brown or gray, often in a wreath (see Harrison [1979] for a photo of markings). Incubation by the female lasts 11-12 days and the young leave the nest 8-10 days after hatching and remain with their parents for another 3 weeks. One successful brood per season is usual. Parasitism by Brown-headed Cowbirds (Molothrus ater) is frequent and the female Yellow Warbler may build another nest on top of the parasitized one. A stack of 6 nests has been observed (Harrison 1979; Lowther et al. 1999).
STATUS. The last confirmed nesting of Yellow Warbler in Texas was in 1956 (Lockwood and Freeman 2004). Oberholser’s map (1974) suggests this warbler was never a very common breeder in Texas. His account suggests loss of riparian habitat and increased cowbird numbers as reasons for the end of Yellow Warbler breeding in Texas. Data from 2423 North American Breeding Bird Survey routes in the United States and Canada on which Yellow Warblers were detected showed only a very slight change has occurred in the population of this species over the last quarter century (Sauer et al. 2005). This trend suggests that Yellow Warblers will continue to be present as migrants in Texas in the future. Text by Robert C. Tweit (2007)
Oberholser, H. C. 1974. The bird life of Texas. University of Texas Press, Austin.
Wise-Gervais, C. 2005. Yellow Warbler (Dendroica petechia). In Arizona breeding bird atlas. pp. 468-469 (T. E. Corman and C. Wise-Gervais, eds.). University of New Mexico Press, Albuquerque.