Edible-nest Swiftlet

The Edible-nest Swiftlet, also known as the White-nest Swiftlet, is a small, enigmatic bird belonging to the swift family. With a body length of approximately 14 cm (5.5 inches), it is a medium-sized swiftlet, characterized by its blackish-brown upperparts and a variable underpart coloration ranging from white to blackish-brown. The tail is short with a subtle notch, and the bird's bill and feet are black. Notably, the legs are very short, with tarsi that are either unfeathered or lightly feathered. This swiftlet has a distinctive flight pattern, with long, narrow wings that form a crescent shape when in motion.

Identification Tips

When observing the Edible-nest Swiftlet, look for its slender body and swept-back wings that give it a crescent silhouette in flight. The bird weighs between 15 to 18 grams and can be identified by its blackish-brown upperparts and varying shades of underparts. Subspecies variations include A. f. micans, which is paler and greyer, and A. f. vestitus, which is darker with a less conspicuously paler rump.

Habitat

These swiftlets are found in a range of habitats from coastal regions to mountainous areas, up to 2,800 meters above sea level in places like Sumatra and Borneo. They are typically seen above forests and open country, as well as forest edges.

Distribution

The Edible-nest Swiftlet has a wide but fragmented distribution across Southeast Asia, including the Andaman Islands, the coasts of Southeast Asia, and the Indonesian Archipelago.

Behaviour

The Edible-nest Swiftlet is an aerial species, spending most of its life on the wing. It feeds on flying insects captured mid-flight and is known to drink while flying. These birds often form large flocks, sometimes mingling with other swiftlet and swallow species. They breed in colonies, preferring coastal limestone caves, rock crevices, cliffs, or even buildings to construct their unique nests.

Song & Calls

At breeding sites, the Edible-nest Swiftlet emits high-pitched, burbling calls. Additionally, it uses a rattling call for echolocation, which is crucial for navigating and locating nesting sites within the darkness of caves.

Breeding

The breeding behavior of the Edible-nest Swiftlet involves building bracket-shaped nests on vertical surfaces using layers of hardened saliva. These white, translucent nests typically measure about 6 cm across and weigh around 14 grams. The species lays two white, oval, non-glossy eggs per breeding attempt.

Similar Species

Germain's Swiftlet was once considered conspecific with the Edible-nest Swiftlet but is now often recognized as a separate species. It can be distinguished by its range and some subtle morphological differences.

Diet and Feeding

The diet of the Edible-nest Swiftlet consists primarily of flying insects. These insects are adeptly caught while the swiftlet is in flight.

Conservation status

The Edible-nest Swiftlet is currently listed as Least Concern by the IUCN. However, some populations, such as those in the Andaman and Nicobar Islands, are under threat due to extensive harvesting for their nests, which are highly valued as a delicacy in Chinese cuisine. Efforts to create artificial bird houses for nest farming are increasing, which may help alleviate pressure on wild populations.