Channel-billed Cuckoo

The channel-billed cuckoo (Scythrops novaehollandiae) is a species of cuckoo in the family Cuculidae. It is monotypic within the genus Scythrops. The species is the largest brood parasite in the world, and the largest cuckoo. The world's largest cuckoo, the channel-billed cuckoo measures between 56–70 cm long. According to a manual on avian body masses, another species of cuckoo, the buff-headed coucal, may have a mean body mass some 11% higher than the channel-billed cuckoo. The bill is bi-coloured, with a grey base becoming straw-coloured at the tip. The bill is large slightly curved and reminiscent of the bills of hornbills; in fact, the bird is sometimes erroneously referred to as a hornbill. The plumage of the adult is pale grey on the head, chest, belly and back, becoming paler and barred lower down on the belly. The wings are darker grey with dark tips on the feathers. The tail is dark grey on top and barred underneath with a black band and white tip at the end. The feet and legs are black, and the eye is surrounded by prominent red skin. While most other very large cuckoos are rather terrestrial (i.e. roadrunners or the genus Neomorphus), the channel-billed cuckoo is fairly arboreal and is capable both in trees and on the ground. The channel-billed cuckoo is a strong flier, with a distinctive, almost hawk-like cross-shaped (cruciform) flight silhouette. There is some sexual dimorphism in both plumage and dimensions, the female having a smaller bill and paler, more barred undersides. The juvenile is similar to the adult but has pale tips to the feathers of the wings, and the rest of the plumage is buff instead of pale grey. The bill is less massive and dirty pink in colour, and the skin around the eye is not red.