The Wikipedia article of the day for August 30, 2017 is Pallas's leaf warbler.
Pallas's leaf warbler (Phylloscopus proregulus) is a migratory bird that breeds in mountain forests from southern Siberia east to northern Mongolia and northeastern China. It is named for German zoologist Peter Simon Pallas, who first described it. It winters mainly in and near southern China, although in recent decades increasing numbers have been found in Europe in autumn. One of the smallest Eurasian leaf warblers, it has a relatively large head and short tail. It has greenish upperparts and white underparts, a lemon-yellow rump, and yellow double wingbars and supercilia. The female builds a cup nest in a tree or bush, and incubates four to six eggs that hatch after 12 or 13 days. The chicks are fed mainly by the female and fledge when they are 12–14 days old. Pallas's leaf warbler feeds on small insects and spiders. It forages in bushes and trees, picking items from leaves or catching prey in short flights or while hovering. The species has a large range, its numbers are believed to be stable, and it is not endangered.