Description wikipedia

The northern hawk-cuckoo or rufous hawk-cuckoo (Hierococcyx hyperythrus) is a species of cuckoo found in eastern China, North and South Korea, far eastern Russia, and Japan. Northern populations migrate to overwinter in Borneo. This elusive species is considered rare over most of its range and many of its life history traits remain understudied. It is known to perch in the crowns of tall trees, making direct observation difficult. The northern hawk-cuckoo, along with the Malaysian hawk-cuckoo (Hierococcyx fugax) and the Hodgson’s hawk-cuckoo (Hierococcyx nisicolor), were all once considered the same species, H. fugax. All three were recently split into their own monotypic species. The genus Hierococcyx are called hawk-cuckoos due to their broad, rounded wings and plumage which lend them great resemblance to Japanese and Chinese sparrowhawks. They are similar enough that in the field hawk-cuckoos are often mistaken for an Accipiter.