It’s that time of year again. As the first thunderstorms of summer bubble and brew on the humid horizon, so too do are the storm birds ramping up in vocal intensity and activity.
Migrating to northern and eastern Australia from New Guinea and Indonesia between August and October each year, the channel-billed cuckoos quickly make their presence known upon arrival with a spine tinglingly loud ‘rawkrawkrawk’ which one friend describes as a chook being strangled.
Growing up dad would lift his hat and look to the west if it called in the late afternoon, checking for signs of amassing cloud. ‘There’s the storm bird’ he’d say as it’s grey crucifix silhouettewould dash into the mulberry tree, leaving a trail of earth splitting sound in its wake, often continuing at intervals throughout the night.
I took it to be certain that it was indeed the harbinger of thunder and rain. It often was, but it’s been on closer observation and study that I’ve begun to understand a little more of its language and behaviour.
This week I sat on a hill overlooking a river flat and watched as a cuckoo emerged silently from a tree, promptly followed by a blue-faced honeyeater and a pied currawong hot on its tail. The chase ended inside the canopy of another tree, with a flurried flapping of wings and a single angry cuckoo cry.
“A silent cuckoo is bound to be up to skulduggery,” said Andrew, my birdy friend.
The particular kind of skulduggery is of the parasitic kind displayed by birds in the cuckoo family who lay their eggs in the nests of other birds (essentially ‘a cuckolded nest’) and let them do all the hard work of raising the chicks.
The channel-billed cuckoo typically likes to lay its eggs in the nests of magpie, currawong, and crow, amongst others.Unlike many other cuckoos, the young birds do not evict the host's young or eggs from the nest, but simply grow faster and demand all the food, thus starving the others. Often the adult female will damage the existing eggs in the nest when she lays her own and she may even lay more than one egg in a single nest. Some reports say that they go so far as to lay eggs that mimic the appearance of their particular host’s eggs.
One bird observer watched the day when the fledgling cuckoo chicks brought up by an unsuspecting currawong began to call. Out of nowhere, in flew the biological parent, and, after some brief conversation, promptly took off with its young, presumably working their way north across the Torres Strait after another restful Aussie summer holiday.