Sombre Nightjar vs Heinrich's Nightjar

Monotonous churring trill; repetitive 'churr' at moderate tempo from East African scrub; lower-pitched and less musical than some relatives; calls persistently at night

Haunting, hollow 'ku-WOO' repeated rhythmically; deep resonant quality; distinctive mournful whistle carrying through Sulawesi forest at night

Uniformly dark sooty-brown upperparts with dense blackish vermiculations; pale buff supercilium and narrow white submoustachial stripe; underparts barred buff and dark brown. Sexes similar.

Rufous-brown and dark brown mottled with buff vermiculations; large pale buff throat patch; pale buff supercilium; no white wing markings; tail darkly barred brown and buff. Poorly known; Sulawesi endemic.