EOL-media-18-https://www.inaturalist.org/photos/3751368

The Pe’ape’a or the White-rumped swiftlets (Aerodramus spodiopygius) can reach a height of 10 cm, and is an unmistakable, delicate black with a subdued grey wash on the underparts and a white rump. The tail has a central notch. During flight, the long, thin sickle-shaped wings and erratic flight with quick shallow wingbeats and intermittent glides are diagnostic. In a steady wind, swiftlets will glide Pe’ape’a has a distinctive klik for echolocation that is given at a rate of about 4/sec. with another call as a twittering chirrup. The klik call may be an additional function for navigation. It is an aerial feeder that exclusively consumes insects above the canopy, under trees, and close to the ground. They normally nest in caves where it is totally dark allowing them to navigate by echolocation. Their nests consist of fine moss, lichen, leaf fibers, and other vegetable material cemented together onto the wall with its own saliva. It only lays two eggs. Pe’ape’a are widespread in the Pacific west region but absent from islands without nesting caves; also found throughout Melanesia and in north Australia. Reference: Watling, Dick and Kelly, Chloe Talbot. 2001. A Guide to the Birds of Fiji & Western Polynesia. Environmental Consultants (Fiji) Ltd. Fiji.