Dusky Crag Martin

The dusky crag martin, Ptyonoprogne concolor, is a small, robust passerine bird belonging to the swallow family. Measuring approximately 13 cm in length, it exhibits sooty-brown upperparts and slightly paler underparts. A distinctive feature is its short, square tail adorned with small white patches near the tips of most feathers, save for the central and outermost pairs.

Identification Tips

When observing the dusky crag martin, look for its broad body, wings, and the aforementioned white tail spots, which are notably smaller than those of its relative, the Eurasian crag martin. The under-tail coverts match the shade of the abdomen's underside, a contrast to the darker under-tail coverts of the Eurasian crag martin. Both sexes appear similar, while juveniles can be identified by the rufous grey tips on their upperparts and wings.

Habitat

This species favors hilly or mountainous regions with cliffs, gorges, and caves for its natural breeding habitat, typically up to altitudes of about 1,800 meters, though it can be found up to 2,000 meters in Thailand. It also adapts well to urban environments and is known to utilize man-made structures such as old forts and stone buildings for nesting.

Distribution

The dusky crag martin is a resident breeder across South Asia, from the Indian subcontinent to southwestern China and the northern parts of Thailand, Vietnam, and Laos. It has also been recorded as a vagrant in Sri Lanka and Borneo and has bred in Malaysia.

Behaviour

Outside of the breeding season, the dusky crag martin may form small flocks. Its flight is typically slow and leisurely, but it can achieve considerable speed when necessary. The species is not known to form large breeding colonies.

Song & Calls

The vocalizations of the dusky crag martin include a soft "chi, chi" contact call and a twittering song, bearing resemblance to the calls of the Eurasian crag martin.

Breeding

Breeding occurs mainly in February and March, and again after the onset of the monsoon in July and August, with usually two broods raised. Nests are open half-cups made of mud with a soft lining, built under overhangs or in crevices on cliffs or man-made structures. Both parents partake in incubating the two to four eggs and feeding the chicks.

Diet and Feeding

The dusky crag martin feeds on a wide variety of insects caught in flight, often foraging near cliff faces or buildings. It exhibits a preference for hunting near vertical surfaces, where air currents can concentrate insect prey.

Predators and Parasites

Predators include birds of prey like the peregrine falcon and the greater false vampire bat, which has been known to prey on this martin.

Conservation Status

With an extensive and expanding range, as well as a large population, the dusky crag martin is classified as Least Concern by the IUCN. It is suspected that the population may be increasing due to the availability of artificial nesting sites.