Japanese Tit シジュウカラ(四十雀)

四十雀の幼鳥

Japanese Tit (Parus minor), also known as Oriental Tit, is a passerine bird which replaces the similar Great Tit in Japan and the Russian Far East beyond the Amur River, including the Kuril Islands. Until recently, this species was classified as a subspecies of Great Tit, but Russian studies have indicated that the two species coexist in the Russian Far East without intermingling or frequent hybridization. As its name suggests, it is quite small (wikipedia). Japanese name is シジュウカラ(四十雀).