Male nightjar (Caprimulgus europaeus) churring after dusk at RSPB Arne, Dorset, UK.
Nightjars are nocturnal or crepuscular birds. The male's song is a sustained churring trill, given continuously for up to 10 minutes, with occasional shifts of speed or pitch. It is delivered from a perch, and the male may move around its territory using different song posts.
In the UK the nightjar is a breeding summer visitor and is red-listed as a cause for conservation concern.