Japanese Leaf Warbler

Japanese Leaf Warbler (Phylloscopus xanthodryas) is an olive-green leaf warbler with yellowish underparts, a long pale eyebrow and light wing bars. Body shape, bill structure, plumage pattern and voice provide the strongest field characters. Age, sex and season may alter its appearance, so identification should combine several features and careful direct field comparisons with similar species in the same habitat (Wikipedia, general species account).

It breeds through Japan except Hokkaido, searches forest foliage for insects and migrates to Southeast Asia for winter; voice helps distinguish it from the closely related Arctic and Kamchatka leaf warblers. Its movements and social behaviour vary through the year, with breeding birds generally more dispersed and non-breeding birds gathering where food is concentrated. Japanese records place it within the country's documented avifauna as a resident, migrant or visitor (Wikipedia, general species account; Wildlife of Japan occurrence records).