Whiskered Treeswift

The Whiskered Treeswift is the smallest of this family. This bird could be an intermediate between the typical swifts with its habits and appearance, and the nightjars, regarding the short bill, the large mouth and the bristles which surround it, making easier to detect the flying preys. The adult male has dark bronze-brown body with white belly, flanks and undertail-coverts. The long wings and the forked tail are deep blue, but the tertial flight feathers are white. The underwing shows blue coverts and white tertial flight feathers. The head is blue to glossy black, and slightly crested. We can see two conspicuous white parallel stripes formed by bold supercilium from forehead to hind nape, and a second stripe from chin back to neck side. The contrast between these white lines and the dark head is strong. The male shows dark chestnut ear-coverts. The short bill is black. The large eyes are dark brown. The short legs and the feet are pale pinkish-brown. The female is similar but she has deep blue-green ear-coverts. The juvenile has finely barred brown, grey and white plumage. The facial stripes are shorter than in adults. The Whiskered Treeswift is a forest-living species which frequents small cover breaks such as tracks or streams, but it also follows the vegetation up around the highest emergent crowns in evergreen forest and locally in tall mangroves. This species occurs from plains up to 1000-1100 metres on slopes, but it is often seen below 800 metres in N Malay Peninsula. The Whiskered Treeswift feeds primarily on insects. It hunts from perches where it sits in upright posture, and from where it can have a good all-round vision of the surroundings. Very agile in flight, it chases insects and small flying arthropods, even amongst the foliage but well below the canopy. The preys are usually taken on the wing, but it also picks off the food items when perched, or by hanging from the tip of a small branch. It may perform short sallies from its perch, close to the surface of the vegetation. The courtship displays are poorly known, but noisy soaring has been reported at least for the largest species. Considering the head patter of the male, it probably enhances the white stripes and the chestnut patches of the ear-coverts by some adapted postures. The breeding pair is territorial during the breeding season.