tannin.net.au

images of australian wildlife

Pallid Cuckoo

Pallid Cuckoo

The same bird as in the picture posted a few months ago, and back on its favourite perch.

Notice the pasture grub it has caught. Perhaps because of the wet La Niña years in 2010 and 2011, the pasture grub population boomed in spring 2011, and again in 2012 - but second time around, the cuckoos had bred up too. Nothing else seems to eat the pasture grubs - they must taste horrible - but cuckoos love them. About twenty birds took up residence around and near the property for the spring; mostly Pallid but Fan-tailed as well, and mostly young birds still not in adult plumage.

Each bird seems to have its own small territory, and two or three favourite perches from which to hunt. They have amazingly sharp eyes, and obviously can spot these small caterpillar from a long way away as they perch and watch for a while, then glide down directly to a grub, which they bring back to the perch for processing.

Most caterpillars taste bad, with a nasty, hairy skin, and birds generally avoid them. Some species have clever ways to get the tasty flesh out from inside the skin. A Grey Shrike-thrush will wedge the grub between two twigs and delicately spoon the flesh out from the torn-off end, like a dog eating marrow from a bone. Crested Shrike-tits split the skin lengthways like a sausage and get at it that way. But the Pallid Cuckoo does the opposite: it bites one end of the grub off and throws it away, then takes the other end in its bill and flicks it several times, quite hard, spraying all the soft green insides — the part that other birds like to eat — out onto the ground. With that complete, the cuckoo eats the empty shell of the caterpillar!

The whole process takes about half a minute. Within two or three or four more minutes, the bird has caught another one. They must eat a phenomenal number of grubs over the course of a season!

Gradually, birds departed, the Fan-tails going first, until there was only one or two Pallid Cuckoos left.

Pallid Cuckoo

Cacomantis pallidus

Creswick, Vic

October 2012

Canon 1D IV

Canon 500/4

3.2° 500mm 500i

f/11 1/640th