Voice
In a group, birds give a 3-4 note creaking whistle 'kruik, kruik, kruik, kruik', which lasts 2-3 seconds. This call is occasionally followed by a melodious two-note whistle, descending and then ascending: 'whu, weeeeeeee', lasting 2-3 seconds, and sometimes preceded by a metallic 'tong'. Also, a whistled 'kriuuk . . . kriuuk', lasting 0.8-1.5 seconds, is mostly given in flight. Creaking and trilling notes are also uttered. Juveniles give a repeated soft cawing 'wree-eek'.
Banggai Crow (Corvus unicolor) [XC95689]
by Frank Lambert from Kokolomboi site 1 above village, Indonesia (call, song)
Banggai Crow (Corvus unicolor) [XC522752]
by id from Kokolomboi, Peleng - above village, Indonesia (call)
Subspecies
No subspecies.
Forms a species pair with Piping Crow (Corvus typicus), which it resembles closely in structure. Until recently, both were thought to belong with the "Slender-billed Crow (Corvus enca) complex", but differ from that in their behaviour and vocalizations.
Similar Species
Slender-billed Crow (Corvus enca) which is larger with more massive bill and proportionately longer tail, and can superficially resemble Cicadabird (Edolisoma tenuirostre) when perched.
References
See References.
BirdLife International Species Factsheet