Booted Warbler

The booted warbler is a reed-and-tree warbler with undistinguished plumage, plain greyish-brown above and paler below, a clear pale supercilium and a short bill with a dark tip, giving a short-winged, rather pot-bellied look with a square-tipped tail. It breeds from central Russia to western China and migrates to winter in the Indian subcontinent as far south as Sri Lanka (Wikipedia, general species account).

It has expanded its breeding range westward in recent decades and now nests as far west and north as Finland, and is a regular vagrant to western Europe (Wikipedia, general species account).