Common Chiffchaff Phylloscopus collybita breeds British Isles to Siberia, with Siberian Chiffchaff P. c. tristis in Altai Mountains and Tianshan in Xinjiang; also vagrant to coastal China. HABITAT Breeds in open woodlands with ground cover. ID & COMPARISON A dull leaf warbler with very little yellow in plumage. Very similar to Mountain Chiffchaff P. sindianus. Crown, nape, and mantle greyish-brown; in fresh plumage, back and rump show olive tinge and wings and outer tail feathers are edged olive-green. In fresh plumage may show faint greyish wingbar. Long, indistinct, buffish-white supercilium and dark brown eye-stripe. Face, breast, and flanks buffish, lacking yellow; underparts otherwise whitish. Mountain Chiffchaff always lacks green in upperparts, wings, and tail and its white supercilium and throat contrast more with adjacent plumage. Greenish Warbler P. trochiloides has better-defined wingbar, supercilium, and eye-stripe, brighter green upperparts, and whiter underparts. Willow Warbler P. trochilus is more green and yellow and has longer primary projection and different song and call. BARE PARTS Bill, feet black. VOICE Sings weet chu weet from prominent perch. Call a weak, single-note peep. — Craig Brelsford
Daniel Bengtsson served as chief ornithological consultant for Craig Brelsford’s Photographic Field Guide to the Birds of China, from which this species description is drawn.