Savanna Nightjar – Chick development

Chan Yoke Meng and Melinda Chan stalked a pair of breeding Savanna Nightjars (Caprimulgus affinis), photographing the pair of chicks daily for 16 days at which time they left the nesting site (above adult with two chicks on day 8).

The eggs were laid on a scrape of ground among sparse low vegetation (above). A clutch of two eggs were laid and apparently incubated by both sexes.

Initially when they approached the nest the adult incubating the eggs flew off to land nearby. It then made the usual “broken wing” display, hoping to lure the pair of intruders away from the nest (above, below). After a few times of such displays the adult got used to the presence of the Meng and Melinda as they kept their distance.

The newly hatched chicks were precocial, meaning that and their bodies were covered with down and the eyes opened very soon after hatching. The chicks were soon able to move around, needing limited parental care. This is contrasted to altrical chicks that are blind and naked at hatching. The former is typical of birds nesting in the open and the latter nesting in cavities or specially constructed nests.

Being precocial, Savanna Nightjar chicks are able to generally avoid being eaten by predators, as their nest is in the open or only partially covered by low vegetation.

By day seven, pin feathers become very obvious, especially on the wing areas (above). The sheaths soon broke open and the feather vanes unfurled to become broad mature feathers (below, showing day 11 chick).

According to Cleere (1999), the chicks of Large-tailed Nightjar (Caprimulgus macrurus) are brooded for about 14 days. In the case of these Savanna Nightjar chicks, it would be around 16 days, as by then the chicks were not found around the nesting area. They must had moved away from the nest with the adults.

Not much information is available on the breeding behavior of the Savanna Nightjar in the literature. The above is our contribution to ornithology.

Chan Yoke Meng & Melinda Chan
Singapore
October 2015

References:
1. Cleere, N., 1999. Family Caprimulgidae (Nightjars). In: del Hoyo, J., Elliott, A. & Sargatal, J. (eds.), Handbook of the birds of the world. Vol. 5. Barn-owls to hummingbirds. Lynx Editions, Barcelona. Pp. 302-386.
2. Cleere, N. & D. Nurney, 1998. Nightjars – A guide to nightjars and related nightbirds. Pica Press, East Sussex. 317pp.
3. Wells, D.R., 1999. The birds of the Thai-Malay Peninsular. Vol. I, Non-passerines. Academic Press, London. 648 pp.