This species averages 51 cm (20") in length.[8] Its long, pointed grey and black tail with a white median band is characteristic of the species. It has a white under-wing patch, visible in flight. The adult has a grey head and leading to a dark grey to blackish pointed crest with an approximate length of 6 cm. The belly and under-tail coverts are white, giving the bird the first part of its name "white-bellied".
The bill is black in male, pea-green in the female (becoming yellowish during the breeding season). Females also tend to be larger, weighing 225g - 250g, where as males only weighed 170g - 225g. The juvenile is similar to adults, with the plumage being more brown, especially on wing-coverts.