Savanna nightjar

The savanna nightjar (Caprimulgus affinis), also known as allied nightjar or Franklin's nightjar, is a species of nightjar found in South and Southeast Asia. Six subspecies are recognised: C. a. monticolus, C. a. amoyensis, C. a. stictomus, C. a. affinis, C. a. timorensis and C. a. propinquus. It was once considered conspecific with the chirruping nightjar. The IUCN Red List has assessed the species to be of least concern because it has a large range and its population trend is stable.

Habitat
Its habitat is open forest and areas with scrub. However, it has recently moved gradually into the metropolitan areas of Taiwan, probably due to the absence of natural predators in that setting. Habitat loss is likely also a significant factor. Impacts of this relocation have included disturbed sleep for residents—due to male savanna nightjars' loud vocalizations at night from January to July—and collisions with aircraft. It is predicted to continue this habitat shift and expand its range into all major western Taiwanese cities.

Description
Its length is about 25 cm, with a wingspan of 64 cm and a body weight of 54-110g. The upperparts are brownish-grey and vermiculated, with pale brown speckles. The underparts are brown, with bars. The savanna nightjar is nocturnal and is recognizable by its characteristic loud chirping calls, mainly given in flight during the evening. Their acoustic features change and can preadapt based upon their habitat.