These enormous birds are found around the north and eastern coastlines of Australia, ranging as far west as Broome and as far south as Sydney, anywhere tall forests with fig trees occur. They are the only bird on the Australian continent which can be mistaken for a hornbill: they are around 60cm (two feet) long, including a 9cm long, heavy, yellow-white bill. Their heads and breasts are white, legs white barred with grey, wings and tail dark grey with black tips, and their eyes ringed with a startlingly vivid red.
Like most cuckoos, they are parasitic breeders. Their target of choice is the Pied Currawong, a largish black-and-white hunter and scavenger which is extremely common along the east coast of Australia. These fearsome individuals, with their glossy black plumage, steak knife beak and glaring yellow eye, are all the more intimidating for their habit of congregating in large, noisy gangs, and few animals dare to mess with them. The channel-billed cuckoo, however, is almost twice their size, and able to disregard their most frenzied bombardments. This is fortunate enough, because even outside of the breeding season the presence of a pair of cuckoos will drive the local flock of currawongs into a beserk rage.
I was lucky enough to see a dramatic demonstration of this extraordinary enmity a year ago, when our quiet Saturday lunch, with the Sydney Morning Herald strewn amongst the bread rolls and prosciutto, was disrupted by a cacophonous honking, gargling noise from the large sydney grey gum in our back yard. The closest description possible in print would be a KWWRRRROOOOAAAARRRRRRKK-WHOOOOP! lasting about two seconds, repeated three or four times in close succession. This was interspersed with the loudest an angriest war cries of the local currawongs I have ever heard. We ran out and craned our necks at the canopy of the approximately 30 metre high tree, where a pair of huge, pale birds were being frantically dive-bombed by the black-and-white currawongs. From the below, their striped trousers and barred tail, along with their general predatory stance, made them look like falcons. A glimpse of that shockingly red eye, however, gave them away as something entirely new and weird. Eventually they tired of the harassment and flew off, although we head their raucous calls around the neighbourhood for a few hours.
The following week, we had the best rain that this thirsty part of the world had seen for months. Which brings me to the most common nickname of these monstrous cuckoos: Storm birds. These migratory birds have a talent for preceding the Wet wherever they go in Australia, and so their KWWRRRROOOOAAAARRRRRRKK-WHOOOOP! is a decidedly welcome noise for many, if not for the poor currawongs.