Edible-nest Swiftlet

Identification

The edible-nest swiftlet is a small swift, typically measuring 14 cm in body length and weighing just 15 to 18 grams. It is a medium-sized representative of the salanganes with a slender build, long narrow wings that sweep back in a distinctive crescent shape during flight, and a short notched tail. The upper body is blackish-brown, while the underparts range from white to blackish-brown depending on the subspecies. The bill and feet are black, and the legs are notably short with usually unfeathered or lightly feathered tarsi.

Subspecific variation is notable across its range: micans is paler and greyer than the nominate form, vestitus appears darker with a less obviously pale rump, germani displays much paler underparts with a broad whitish rump, and amechanus resembles germani but with a greyer rump.

Range & Habitat

The edible-nest swiftlet is found throughout Southeast Asia, with eight recognized subspecies distributed across a range extending from the Andaman and Nicobar Islands through the Malay Peninsula, Sumatra, Borneo, the Philippines, and the Lesser Sunda Islands to Timor. These birds occur in diverse habitats from coastal areas to mountains, feeding over forests, forest edges, and open country, with records from elevations up to 2,800 metres above sea level on Sumatra and Borneo.

Behaviour & Diet

The edible-nest swiftlet spends most of its life airborne, catching flying insects on the wing and even drinking while in flight. These birds typically feed in large flocks, often associating with other swiftlet and swallow species. They breed in colonies in coastal areas, utilizing limestone caves, rock crevices, cliff faces, and occasionally buildings as nesting sites.

The nest is a remarkable structure—a bracket-shaped creation composed entirely of hardened layers of the bird's own saliva, attached to vertical surfaces. Nests typically measure about 6 centimetres across with a depth of 1.5 centimetres and weigh approximately 14 grams. Two white, oval, non-glossy eggs are laid per clutch. At breeding colonies, these swifts emit high-pitched burbling calls and use echolocation with rattling calls to navigate through the darkness of caves.

Best Time & Places to See It

The edible-nest swiftlet is best observed during the breeding season when large colonies gather at cave systems and cliff faces throughout Southeast Asia. Limestone cave regions in countries such as Indonesia and Malaysia are particularly productive locations. The birds' constant aerial activity and gregarious feeding behaviour make them relatively easy to observe once you locate an active breeding or roosting site, though they are always on the wing and never voluntarily settle on the ground.

Photography Tips

Photographing this species presents challenges due to its small size, rapid flight, and crescent-shaped wing profile. A fast shutter speed is essential to freeze the bird's swift, erratic movements through the air. Wide open spaces above forests, forest edges, and coastal areas offer the best opportunities for flight photography. Early morning and late afternoon often provide better lighting conditions for capturing these swift hunters in action.