Figures 340, 341 (above, below). Difficulties inherent in the field identification of Empidonax flycatchers may largely explain the paucity of California records of the Yellow-bellied Flycatcher. Of the 16 birds positively identified (see also Appendix H), seven were examined in hand—six at Southeast Farallon Island, one on San Nicolas Island, Ventura County. The rest, such as this first-fall bird (1989-114), are from well-known migratory stopover sites on the mainland—in this case Galileo Hill, Kern County. This widely seen individual was present there from 27 September to 1 October 1989 and was photographed on 27 September (Larry Sansone, above) and 30 September 1989 (Ned Harris, below).

Figure 341.

 

Figure 342. The Yellow-bellied Flycatcher strays to California mainly during September, with a smaller number recorded in October. See also Appendix H.

 

Figure 249. Compared with a “Western” Flycatcher (Empidonax difficilis/E. occidentalis), this first-fall Yellow-bellied Flycatcher—photographed on 4 October 2001 at Southeast Farallon Island—has a rounder head, slightly shorter tail, more even eye-ring, crisper and more contrasting whitish wing edgings, lack of ochre in the wing bars, and greener back (2002-013; Kristie N. Nelson).

 

 

 

 

 

 

 

YELLOW-BELLIED FLYCATCHER Empidonax flaviventris (Baird and Baird, 1843)

Accepted: 16 (62%)	Treated in Appendix H: yes
Not accepted: 10	CBRC review: all records
Not submitted/reviewed: 0	Large color image: see Figures

This empid’s northern breeding limit extends from east-central Alaska (NAB 58:584, 59:641), central Yukon, and northeastern British Columbia (and central British Columbia, where local) east to Labrador and Newfoundland. The southern breeding limit stretches from northern Minnesota to northeastern Pennsylvania and southern Vermont, and an isolated population formerly existed in West Virginia/western Virginia. The species winters from southern Tamaulipas to western Panama and migrates primarily over land around the western Gulf of Mexico. In North America, vagrants have occurred casually or accidentally westward to Montana, Arizona, Nevada, northern Baja California, and Nayarit, and additional extralimital records come from Cuba, the Bahamas, and Greenland.

DeSante et al. (1985) detailed California’s first two records of the Yellow-bellied Flycatcher, both of which involve first-fall birds on Southeast Farallon Island—the first on 16 September 1976 and the second on 27 and 28 September 1984 (a bird found dead after being identified in the field and in hand). The state’s 16 records fall between 3 September and 16 October, and all but three involve birds found during the month of September (Figure 342); see also Appendix H. Adults molt on the wintering grounds, and so are heavily worn during fall migration, unlike the clean-looking first-fall birds that account for all of the accepted California records to date. That six records come from Southeast Farallon Island is perhaps unsurprising, but that an equal number come from eastern Kern County is remarkable. One might expect records from the coastal mainland to begin catching up with the deserts and islands now that identification criteria are becoming better known (but note that Baja California’s two records are also from inland locales).

Field identification of the Yellow-bellied Flycatcher versus the Western Flycatcher complex (E. difficilis/E. occidentalis) presents a challenge that should not be taken lightly, but the issues have become much better known through improved field guide treatments and other sources (e.g., Whitney and Kaufman 1986, Pyle and McCaskie 1992, Pyle 1997b, Heindel and Pyle 1999).

 

 

[ACADIAN FLYCATCHER Empidonax virescens (Vieillot, 1807) – see hypothetical section]