The Middendorff's grasshopper warbler (Helopsaltes ochotensis ) is a species of Old World warbler in the family Locustellidae.It breeds in East Siberia to North Japan - Kamchatka Peninsula and North Kuril Islands and winters in the Philippines, Borneo and Sulawesi and in small numbers China, Hong Kong, South Korea, Malaysia, Taiwan and the U.S.A.
The common name commemorates Alexander Theodor von Middendorff (1815–1894), a German–Russian naturalist who traveled extensively in Siberia.
15.5 cm (6.1 in) length. Crown, nape, lores, eye-stripe greyish brown. Mantle browner and more olive. Supercilium pale creamy extending to ear coverts. Rump and uppertail coverts more yellowish or rufous brown. Graduated, white-tipped tail may appear rounded.Voice: Song; high-pitched, spaced chit, chit, precedes trilled trrrrrrrr-schoy-schoy-schoy, call; tluk, tluk,.... also a short song flight. Habitat: Forests near water and scrubwoods.