ASH-THROATED FLYCATCHER Myiarchus cinerascens cinerascens (Lawrence)

Field characters.—Bulk about twice that of Junco; length 8-1/2 inches; relatively slender in outline, tail as long as body, head with a blunt crest. No sharply contrasted markings; whole coloration pale-toned; breast light gray, belly white tinged with yellow; head and back grayish brown; wings and tail showing reddish brown areas when expanded; closed wing crossed by two dull whitish bars. Perches low in open situations, turning head from side to side, and making frequent changes of position. Voice: A throaty, staccato one- or two-syllabled call, descending in pitch, ker, ker-cherr', or kut-truh', with audible rolling of r's; also a 'song,' a loud rolling tuck' a roo, repeated many times at irregular intervals of a second or more.

Occurrence.—Summer visitant west of Sierras; common throughout Lower and Upper Sonoran zones to as far east as El Portal; once observed by us in Yosemite Valley, on north side near foot of trail to Yosemite Fails, June 7, 1915; noted also in the Valley June 20 to 25, 1893 (Emerson, 1893, p. 179). Frequents open situations, chiefly in chaparral, especially where sparingly interrupted by oaks; forages usually alone, rarely in pairs, never in flocks.

The Ash-throated Flycatcher resembles the Western Kingbird in general form and tone of coloration, but differs unmistakably in habits and demeanor. It has none of the aggressive, belligerent actions which characterize the kingbird, but attends to the business of catching insects in a pleasingly quiet manner. Unlike many of the Flycatcher tribe, the Ash-throat does not often return to the same location after sallying forth to capture an insect, but usually moves on to a new perch, evidently preferring to go after its prey rather than passively wait for the latter to chance by. Often, when taking flight for but a short distance, the bird retains the upright posture of its body, and with its tail drooped and slightly expanded flutters from one perch to the next. Nor is it so restricted in home range as the kingbird. Most flycatchers, the kingbird included, are wont to remain in a restricted area after once being established for the season, but the Ash-throat seems to be more enterprising and ranges widely over the brushlands. When perched its rather upright posture, together with its slightly crested head and long tail held in line with the back and body, gives it a characteristic outline, recognizable almost as far as the bird may be seen at all.

In the Upper Sonoran Zone, for example at Pleasant Valley or Coulterville, the Ash-throated Flycatcher is common on the brush-covered hill sides, flying from one dead greasewood stub to another, snapping up various insects attracted there by the flowers of the greasewood, yerba santa, and deer brush, and uttering at intervals its not unpleasant throaty call notes.

In the dry bed of a cañon below the chaparral-covered hills west of Coulterville one of these flycatchers was watched for some time on a morning in May. This particular individual faced in, toward the foliage of the live oak in which it perched, and several times was seen to gather insects from the foliage within range by merely reaching for them. Once it took a smooth worm and, gulping it only part way down, flew off to another perch before completing the act of swallowing. Another insect taken earlier was swallowed with much gulping, the contractions of the throat being easily seen.

This flycatcher has access to an abundant food supply in the chaparral belt, and there is no other species of flycatcher there to compete with it. This food supply, however, is greatly reduced or entirely gone during the cold season of the year and so the Ash-throat departs; it migrates south early in the fall and spends the winter months in Mexico and Central America. The species is a late arrival in spring, for on May 24 at Pleasant Valley and on May 26 at Snelling birds of this species, evidently still in migration, were seen working in a general northeasterly direction. On the earlier date about 25 individuals were observed, many more than would have been recorded over the same census route had there been no migrants in the region.