By Danielle Davis
Images by Melanie Barsony & Sharon McGrigor
Standing at 58 - 65 cm, the Channel-billed Cuckoo is the largest parasitic cuckoo in the world. It parasites at least eight of our native bird species, notably the Collared Sparrowhawk, White-winged Chough, Magpie-lark, Magpie, Pied Currawong, Australian Raven, Little Crow and Torresian Crow.
The adult female cuckoo lays one egg, but sometimes she may even lay two, in a single nest and will often damage the existing eggs in the nest when she lays her own. Unlike many other cuckoos, the young birds when they hatch do not evict the host's young or eggs from the nest, but simply grow faster than the hosts chicks, if they hatch at all, demanding all the food, thus starving the other chicks. When the host’s chicks decline and eventually die, they are removed from the nest by their parents, who then tend to and raise the larger Channel-billed Cuckoo chick, or chicks, until it has fledged and left the nest. More often than not, the cuckoo chick will grow larger than their foster parents making it quite a challenge for them to keep up with all it’s feeding. They do not recognise it as not being their own and, like all good parents, will run themselves ragged trying to sustain their voracious appetite.
They are a migratory bird making the journey south annually to breed in northern to eastern Australia from Papua New Guinea and Indonesia between August and October. The birds then leave Australia in February - March flying the thousands of kilometres back to Papuasia.
While in Australia they tend towards living in mainly tall open forest areas, especially along watercourses and rainforest streams, particularly where fig trees abound, and usually where host species occur. Ranging from coastly and subcoastal northern and eastern Australia, from Kimberleys to Bega, NSW, and inland irregularly to Lake Eyre drainage.
Their long tail and long wings give this cuckoo a crucifix-shaped silhouette in flight.
Sexes look similar with the male slightly larger than the female. Head, nape, throat and breast light to smoky grey, belly, abdomen and vent whiter, indistinct darkish-brown barring on flanks. Wings, back, rump and tail all grey tending to black-brown, central 2 tail feathers tipped white with a broad subterminal black-brown bar.
Eye bright scarlet-red, facial skin deep red to pink scarlet maroon, bill large and toucan like downward curve – 55-70mm from nostril to tip – pale to mid grey with whitish tip and notched edges, inside of mouth deep pink to pale pink, feet plumbeous grey to deep pink-scarlet.
Immature birds distinguished by their olive to brown eye and smaller bill. Eggs (usually 1-2) slightly glossy, dull white to yellowish or even reddish brown, spotted and blotched with light to mid-brown and lavender, oval-rounded shaped about 43 x 29 mm.
Unusual, not only for their shear bulk, but also because their favoured foods are our native figs and fruits. They will also feed on other fruits and berries, occasionally eggs and the young of other birds, as well as large insects; wings and tail are spread as the cuckoo reaches out with its formidable bill to pluck an insect, such as a stick insect, from foliage. While breeding they are solitary or in territorial pairs, but later may gather in small foraging flocks.
A courtship display precedes copulation: in response to the female’s quiet reedy trumpeting from a high branch, the male offers her an insect; as he approaches, she squats low on the branch and spreads her wings; then he mounts her and she takes the food.
Although they are not nocturnal birds (night birds) in the strict sense, Channel-billed Cuckoos are notorious for calling all night long during the breeding season. The call of the Channel-billed Cuckoo, a loud 'kawk' followed by a more rapid, and weaker 'awk-awk-awk...', is as distinctive as the bird's appearance. The call may be given when perched, but is most often given in flight.
Reader's Digest Complete Book of Australian Birds,
Websites:- amonline.com.au, birdway.com.au, birdsinbackyards.net.