The Ash-throated Flycatcher is a common breeding bird in much of southern and western Texas, much less common in the northern and western Panhandle. Although nesting for many cavity-nesting birds is limited by the supply of natural cavities and woodpecker holes, this species has adapted to human-created cavities.
The vocalizations of Ash-throated Flycatcher are very useful in distinguishing the species from other visually similar members of its genus. Differences in habitat preference and vocalizations may account for the lack of hybridization among Myiarchus flycatchers in Texas (Dixon 1989).
DISTRIBUTION. During the 1987-1992 field work of the TBBA project, atlasers found Ash-throated Flycatchers widely distributed in the western two-thirds of Texas, east to the 97th meridian. Breeding records were more scattered in the western Trans-Pecos and northern High Plains regions (as defined by Lockwood and Freeman 2004).
North American Breeding Bird Survey (BBS) data from the 103 routes in Texas on which Ash-throated Flycatcher was detected show the highest relative abundance (10-30 flycatcher per 40 km [25 mi] route) in the Trans-Pecos, western Edwards Plateau and northwestern South Texas Brush country regions. Numbers drop to 3-10 per route in the western Rolling Plains, the remainder of the South Texas Brush Country and Coastal Sand Plain. In the rest of their range shown on the TBBA map, densities were less than 1 flycatcher per route (Sauer et al. 2005).
Outside Texas the species breeds from eastern Washington and Oregon, California, Nevada, Utah and Colorado south through east and central Mexico and Baja California to the Isthmus of Tehuantepec. In winter Ash- throated Flycatchers are found along both coasts of Mexico and south to Honduras (Cardiff and Dittmann 2002).
SEASONAL OCCURRENCE. Ash-throated Flycatchers migrate north through Texas from about March 8 to early May with most arriving in late March. The breeding season extends from early April to late July (eggs were found from April 12 to June 17 with young in the nest as late as July 17). Southbound migration occurs from about July 17 to December 5 with most individuals passing between early August to mid-September (Oberholser 1974, Lockwood and Freeman 2004).
BREEDING HABITAT. Ash-throated Flycatchers breed in Texas from near sea level to 2100 m (7000 ft) in a variety of habitats ranging from desert scrub (including mesquite, acacia and cactus) to juniper-oak woodlands (Oberholser 1974).
Nests are placed in natural cavities or abandoned woodpecker holes in the species listed above, cavities in cottonwood trees in riparian areas or cavities in man-made objects. Nests are usually below 6 m (20 ft) above ground. The cavity is filled with forbs, rootlets, grass and bits of manure; the cup is lined with a felted mass of animal hair.
The female usually lays 4-5 creamy white to pinkish eggs which she incubates for 15 days.The eggs are indistinguishable from those of Brown-crested Flycatcher (M. tyrannulus) and similar to those of Great Crested Flycatcher (M. crinitus). Young birds leave the nest 13-17 days after hatching and the parents may raise two broods in a year in Texas. The species is a rare host to cowbirds (Harrison 1979).
STATUS. Ash-throated Flycatcher is common to uncommon in spring and summer in the western half of Texas (Lockwood and Freeman 2004). The distribution map in Oberholser (1974) is similar to the TBBA map.
BBS data for Texas show a +1.5 % population change per year for the period 1966-2004 and a trend for the total range in the United States of +1.0% per year based on 516 routes (Sauer et al. 2005).
These figures are encouraging, especially for a cavity-nester. BBS data (Sauer et al. 2005) also show that California, Arizona, New Mexico and Texas hold the vast majority of the United States breeding population. Based on the ratio of Texas routes on which the species was found to the country-wide total, this state contains around 20% of the United States breeding population. Birdwatchers should be able to find this species easily in much of western Texas for years to come.
Text by Robert C. Tweit (2006)
Cardiff, S. W. and D. L. Dittmann. 2002.Ash-throated Flycatcher (Myiarchus cinerascens). In
The birds of North America, No. 664 (A. Poole and F. Gill, eds.). The Birds of North America, Inc., Philadelphia, PA.Dixon, K. l. 1989. Contact zones of avian congeners on the southern Great Plains. Condor 91: 13-22.
Harrison, H. H. 1979. A field guide to western birds’ nests. Houghton Mifflin, Boston, MA.
Lockwood, M. W. and B. Freeman. 2004. The TOS handbook of Texas birds. Texas A&M University Press, College Station.
Oberholser, H. C. 1974. The bird life of Texas. University of Texas Press, Austin.
Sauer, J. R., J. E. Hines, and J. Fallon. 2005. The North American Breeding Bird Survey, results and analysis 1966-2004. Version 2005.1. USGS Patuxent Wildlife Research Center, Laurel MD (Web site, http://www.mbr-pwrc.usgs.gov/bbs).