Apus pacificus
Family: Swifts · Status: Common migrant · Size: 18–19.5 cm · Conservation: Least Concern
Breeds in Siberia and east Asia, migrating south to Hong Kong, mainland Southeast Asia, Indonesia, and Australia.
Has dark grey upperparts, scaled underparts, long sickle-shaped wings, a sharply forked tail and a white rump. Separated from Common Swift by the presence of the white rump, scaled underparts and a pale, diffused throat.
Open habitats and forested areas; regularly seen in large flocks during peak migration.
Feeds on small insects taken in flight.