Like other nightjars, the white-winged nightjar is active at dusk, dawn and throughout the night, when it flies over hillsides and hilltops hunting for food. It flies slowly, and frequently glides, one to two metres above the grass, searching for moths, beetles and flies. This nocturnal hunter can also be found perched on low plants, termite mounds or palms, where it will make sudden short sallies to snatch prey from the air (2).
During the breeding season, the white-winged nightjar male defends small display territories in open areas on the upper slopes of ridges, which usually contain one to three display areas. Each display area typically consists of a vertical perch and a low anthill, separated by a few metres, and is used by the male during moonlit nights to perform courtship displays. From the elevated perch, the male flies in a gentle arc with ‘butterfly-like’ wing beats and the wings held back. They alight briefly on top of the anthill before flying with strong wing beats back to the perch. During these displays, the male produces an unusual, mechanical grrrrt sound, thought to be produced by the wings (6).
Relatively little is known about breeding in the white-winged nightjar, as the first ‘nest’ was discovered as recently as 1997. There is no constructed nest as such; rather, the clutch of two eggs is laid directly on the ground, adjoining a small ‘clearing’, in grassland (4). In Paraguay, nesting occurs between September and December, with the female apparently carrying out all the incubation, brooding and chick provisioning duties on her own (4).