Jungle Nightjar
Caprimulgus indicus
The jungle nightjar is about 21–24 cm long with the Sri Lankan population (ssp. kelaarti) being smaller. Mostly grey with black streaks on the crown, it lacks a conspicuous wing patch which is rufous. The tail is greyish with well separated narrow black bars. The male has a white throat patch that is broken at the middle. The female has a rufous throat patch and submoustachial streaks. The usual call is a series of thacoo or chuck notes (at the rate of 5 every 2 seconds) like a distant engine. The song is a slow and regular, series of FWik-m notes, repeated for as long as 10 seconds.
ID text from Wikipedia, CC BY-SA 4.0
Red-necked Nightjar
Caprimulgus ruficollis
The variegated plumage resembles the European nightjar. The adult is lichen-grey, barred and streaked with buff, chestnut and black. The underparts are barred. It is larger and longer-tailed than the more widespread species, and has a rufous neck-collar. Both sexes have white wing spots, tail sides and throat. During the day this nightjar lies silent upon the ground, concealed by its plumage; it is difficult to detect, looking like a bit of lichen-covered twig or a fragment of bark. The length is 32 cm, and the wingspan 64 cm. Voice: Its call is a repetitive mechanical kyok-kyok-kyok..., which rises and falls as the bird turns its head from side to side. When it churrs, the bird lies or crouches along a branch or rail, but it will sing from a post. During courtship, and occasionally at other times, it uses a mechanical signal, a sharp cracking sound, caused by clapping the wings together over the back.
ID text from Wikipedia, CC BY-SA 4.0

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Play today's Daily BirdPhotos and recordings are credited to their authors under the licence shown. Full profiles: Jungle Nightjar and Red-necked Nightjar.