Green-crowned warbler Phylloscopus burkii

Medium-sized warbler with green upperparts, yellow underparts, a bright yellow eyering, and a gray crown bound by two black stripes. Extremely similar to several closely related species; luckily, range prevents much confusion throughout these species’ natural ranges. Primary confusion species is Whistler’s Warbler, from which it may be distinguished visually, albeit with significant difficulty. In Green-crowned, note weak break at rear of eye-ring (while the eyering of Whistler’s is thickest at the back end), longer and more slender bill, shorter tail, more solidly black crown stripes, and slightly brighter green upperparts. As with many physically similar species, using a combination of these field marks is preferable in identification. Active, frequently flitting about in the lower levels of forest, sometimes associating with foraging flocks. Breeds in both evergreen and deciduous broadleaved forest in hilly and montane areas; moves to lowland areas in the winter. Averages lower than Whistler’s Warbler in altitudinal breeding preference, and overlap is fairly minimal. Song is a strung-together series of ringing “witchy-witchy-witchy” or “tzewee-tzewee-tzewee” phrases, and unlike song of Whistler’s, includes jumbled trilling segments. Call is a short, succinct “wit wit!”.