Aerodramus terraereginae (E.P.Ramsay, 1875)

Size and Morphometrics

This species, Aerodramus terraereginae, measures 11–12 centimetres (4.3–4.7 in) in overall length, with a wing length ranging from 107–118.2 millimetres (4.21–4.65 in) and a body weight of 10.5–12.5 grams (0.37–0.44 oz).

Plumage Coloration

Its upperparts are dark grey-brown, while its underparts are uniformly greyish. It has pale feathers on the forehead and lores.

Rump and Tail Morphology

The rump is normally pale greyish, but may occasionally be darker, and the tail is slightly forked.

Subspecies Morphology

The subspecies A. t. chillagoensis is smaller and paler than the nominate form, with an average weight of around 9.39 grams (0.33 oz).

Vocalizations and Echolocation

This swiftlet has a high-pitched flight call, and produces metallic clicking calls for echolocation when inside its breeding caves.

Nominate Subspecies Range

The nominate subspecies A. t. terraereginae is found in tropical north-east Queensland, Australia, ranging from the Claudie River on Cape York Peninsula south to the Eungella Range near Mackay.

Nominate Subspecies Habitat and Elevation

It occurs mainly near the coast, including on multiple offshore islands, and can be found from sea level up to 1,000 metres (3,300 ft) elevation, though it is most common below 500 metres (1,600 ft).

Chillagoensis Subspecies Distribution

The subspecies A. t. chillagoensis occurs further inland, in the area around Chillagoe west of the Great Dividing Range.

Breeding Period

Breeding for this species takes place from July to March.

Breeding Colony Location

It breeds in colonies that can hold hundreds of individuals, which are located in caves, or sometimes among boulders.

Nest Characteristics

Nests are attached to cave walls or ceilings 2–20 metres (6 ft 7 in – 65 ft 7 in) above the ground; they are translucent and basket-shaped, built from saliva mixed with grasses, casuarina needles, twigs, and feathers.

Clutch Details

Two clutches are laid per breeding season, and each clutch contains one single white egg.

Incubation Process

Both parents incubate the egg for approximately 26.5 days. Incubation of the second egg is warmed by the first chick.

Juvenile Development

Juveniles remain in the nest for around 46–51 days after hatching.

Diet Composition

The Australian swiftlet feeds while flying, preying on insects and drifting spiders.

Foraging Habitat

It forages in flocks over rainforest edges, savanna, pastures, beaches, and gorges.

Foraging Behavior

It typically feeds within 30 kilometres (19 mi) of its breeding colony, and leaves the nest for approximately 30-minute hunting periods.