SAN JOAQUIN BEWICK WREN. Thryomanes bewicki drymoecus Oberholser

Field characters.—About half bulk of Junco; smaller than Cañon or Rock Wren, but larger than House and Winter Wren; tail, long, nearly as long as body. Plumage plain dull brown above, ashy white beneath; a conspicuous white line over eye; grayish white patches on ends of outer tail feathers. (See pl. 53d). Movements jerky. Voice: Song of male a lively series of notes, full of sibilants, ending in three or four clear calls, seek, seek, suk, terrr, tuh, whoit, seet seet, seet, tsee; call note a hoarse tserk, also a softer chee-chee-chee-chee.

Occurrence.—Common resident chiefly of Upper Sonoran Zone, on west slope of Sierra Nevada. Recorded from El Portal and near Coulterville westward to Lagrange and Snelling. Forages in mixed growths, more often in brush than in trees. Solitary.

The San Joaquin Wren, a local race of the widely distributed Bewick Wren (called Vigors Wren in some books on western birds), is common in the Upper Sonoran foothills, and some are to be found still farther to the west, in the San Joaquin Valley, in the bottom lands of the Merced and Tuolumne rivers. There are four species of wrens in the foothill country, yet no two meet each other in serious competition. The Cañon Wren is found on rocky cañon walls, the Rock Wren about earth bluffs and rocky outcrops, the House Wren in oak trees, whereas the San Joaquin Wren inhabits the mixed growths comprising small trees and brush.

This wren is nowhere abundant. Individuals or pairs are located at wide intervals through the chaparral country, usually so far apart that not more than one bird will be within hearing from a single post of observation. Our records show that in a 4-hour census at Pleasant Valley, on May 23, 1915, 6 were heard in song; an equal number were noted during 3 hours of observation at Snelling, on May 26, 1915. At El Portal in November and December, 1914, only one or two of the birds were recorded in an average forenoon's reconnoissance. But then they were more quiet and more absorbed in foraging under dense cover.

The garb of the San Joaquin Wren is quite plain, being dull brown above and ashy white beneath. Over the eye is a conspicuous white stripe which at all times forms the best single character for sight identification of the species. (See pl. 53d). When moving about in its favorite haunts the bird does a great deal of twisting to one side or the other, and jerks the tail this way and that, but it does not 'curtsy' or bob down and up spasmodically like the Cañon Wren or the Rock Wren. While engaged in foraging it is not an uncommon thing for this wren to drop down and hop twistingly about on the ground, with the tail held aloft. But when the male sings he is apt to perch rather quietly; and then his tail hangs directly downward in the manner of a thrasher.

The Bewick Wren has a rather extensive repertoire, consisting of several phrases or 'small songs' each of which is itself set in character. Variety is displayed in the manner or sequence in which these are put together. There is a 'full song,' as indicated at the beginning of this chapter. Another rendering, taken down in the field, was see, see, see, see, sing, sing, sing, sing, sir. Always the song is quick timed and full of sibilants. The ending is usually of three or four clear notes, see, see, see, see; not infrequently these alone are given as a song. Again a bird will call eent, eent, eent, eent, rather slowly, and then sing zree-ter-er-er-er, the latter being a trill of short duration. The call notes of the species differ in quality markedly from time to time even in the same individual. Some times they are coarse, staccato utterances, given in sharp series; again, they are low, mildly harsh sounds, uttered now and then, singly.