Pallas's leaf warbler (Phylloscopus proregulus)

The Pallas's leaf warbler or Pallas's warbler is a leaf warbler 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 formally described it. It is strongly migratory, wintering mainly in southern China and adjacent areas of southeast Asia, although in recent decades increasing numbers have been found in Europe in autumn.

Pallas's leaf warbler is one of the smallest Eurasian.. more