In China, Rusty-flanked Treecreeper Certhia nipalensis occurs only in southeast Tibet and around Gaoligong Mountains in western Yunnan. HABITAT & ID Breeds at higher altitudes (in Tibet to 3500 m [11,480 ft.]) and has a more prominent buffish-white supercilium than Sikkim Treecreeper C. discolor and Hume’s Treecreeper C. manipurensis. Has shorter and straighter bill than those species and richly colored rufous flanks and breast sides that contrast with white throat and buffish-white breast. Underparts of Sikkim Treecreeper and Hume’s Treecreeper show little contrast, and Hodgson’s Treecreeper C. hodgsoni has duller, less contrasting, buffish flanks. Bar-tailed Treecreeper C. himalayana also lacks bright rufous on underparts and has conspicuous black bars on tail. Hodgson’s Treecreeper and Bar-tailed Treecreeper breed at higher elevations than Rusty-flanked, but there is overlap with those two species as well as with Sikkim and Hume’s. Overlap especially possible in winter, when all five species tend to be found at lower elevations. BARE PARTS Bill blackish, with pale base to mandible; feet brown. VOICE High-pitched song introduced with tsit call emitted 1 to 3 times and followed by rapid metallic trill lasting 1 to 2 seconds. Also thin calls like other treecreepers. — Craig Brelsford
THE TREECREEPERS OF CHINA
shanghaibirding.com has research on all seven species of treecreeper in China. Click any link:
Eurasian Treecreeper Certhia familiaris
Hodgson’s Treecreeper C. hodgsoni
Bar-tailed Treecreeper C. himalayana
Rusty-flanked Treecreeper C. nipalensis
Sikkim Treecreeper C. discolor
Hume’s Treecreeper C. manipurensis
Sichuan Treecreeper C. tianquanensis
ACKNOWLEDGEMENTS
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.