The Japanese bush warbler (Horornis diphone ), known in Japanese as uguisu (鶯), is an Asian passerine bird more often heard than seen. Its distinctive breeding song can be heard throughout much of Japan from the start of spring.
The Japanese bush warbler is olive brown above and tending toward dusky colors below. It has pale eyebrows. It has a beak that curves up making it look like it is smiling. The bird is typically 15.5 centimetres (6.1 in) in length.
The Japanese bush warbler is a common year-round resident throughout Japan (except Hokkaidō) and the northern Philippines. In summer the Japanese bush warbler can also be found in Hokkaidō, Manchuria, Korea, and central China. In winter, the bush-warbler can also be found in southern China and Taiwan.Show More
It was introduced to Oahu between 1929–1941 and has since spread throughout the main Hawaiian Islands.
In summer it ranges from low hills to high mountains, preferring bamboo thickets and black pine trees. In winter it seeks cover at lower elevations.Show Less