Birdsong field guide
Cook's Swift
Apus cooki
Cook's Swift is a large, dark aerial insectivore with a prominent white rump, formerly treated as a subspecies of the Pacific Swift.
What it sounds like
A rapid, high-pitched buzzing trill or a series of harsh, screaming 'scree' notes.
Field notes
- It nests almost exclusively in limestone caves, adhering its nest to vertical walls using saliva.
- The species was split from the Pacific Swift (Apus pacificus) complex due to its distinct vocalizations and DNA.
- It possesses a shallower tail fork and darker underparts compared to its close relative, the Fork-tailed Swift.
- Like other swifts, it is highly aerial and is capable of sleeping and mating while in flight.
- It is primarily a resident species in its range, though some altitudinal migration may occur during the non-breeding season.
Habitat
Karst limestone regions, mountainous terrain, and open skies over forests.
Range
Southeast Asia, including Thailand, Myanmar, Indochina, and southern China.
Similar & commonly confused birds
Heard a Cook's Swift?
Open Birdsong, tap record, and identify the bird singing near you in seconds — then collect it in your field journal.
Identify a bird by its song