Asian House Martin

Overview

The Delichon dasypus is a migratory passerine bird belonging to the swallow family Hirundinidae. It is a cliff-nesting martin that breeds in colonies and spends the winter at lower altitudes or in Southeast Asia.

Identification

• Small passerine, approximately 12 cm in length, with a slightly forked tail.
• Plumage features dark steel blue or blue-black upperparts, a contrasting white rump, and pale grey underparts.
• The bill is black, and the legs are brownish-pink, distinctly covered with white feathers.
• The song is a rippling metallic trill, accompanied by a dry, metallic cheep that is more rasping than that of the common house martin.

Habitat

This species prefers valleys and gorges in mountainous areas or coastal cliffs where natural caves provide nest sites, and it also breeds on large man-made structures such as temples and power stations. Its range spans the Himalayas, central and eastern Asia, and parts of Southeast Asia, with specific altitudes varying by subspecies from 1,500 m to 5,000 m.

Diet

The Asian house martin feeds primarily on small insects taken in flight, usually caught high in the air, including flies, aphids, and winged ants. However, the presence of terrestrial springtails and Lepidoptera larvae in its diet indicates that food is sometimes picked from the ground.

Did you know?

Unlike its relatives, this species frequently leaves its nest enclosure open, building a deep mud cone that resembles a larger version of a barn swallow nest. This was found in a Russian study to account for half of the nests in a Baikal research area.