About Horornis diphone (Kittlitz, 1830)
The Japanese bush warbler, scientifically known as Horornis diphone (Kittlitz, 1830), has an olive brown back and upper body, with darker dusky-toned underparts. It has pale eyebrows, and an upward-curving beak that gives it the appearance of smiling. Adults of the species are typically 15.5 centimeters (6.1 inches) long. This warbler is a common year-round resident across most of Japan, except Hokkaidō, and in the northern Philippines. During the summer breeding season, it can also be found in Hokkaidō, Manchuria, Korea, and central China. In winter, it additionally occurs in southern China and Taiwan. It was intentionally introduced to the island of Oahu between 1929 and 1941, and has since spread across all of the main Hawaiian Islands. In summer, the Japanese bush warbler occupies areas from low hills up to high mountains, and strongly prefers habitats with bamboo thickets and black pine trees. In winter, it looks for sheltered habitat at lower elevations.
