Thursday, 2 October 2014

Grey Butcherbird

A Grey Butcherbird Cracticus torquatus arrives at its nest with food for its young
The bird breeding season around Canberra is a protracted affair, with some birds like the Wedge-tailed Eagles and Superb Lyrebirds laying their eggs in winter, as well as a few small birds such as, for example some Buff-rumped Thornbills. At the moment a White-browed Scrubwren is incubating eggs in a nest in our garden - due to hatch any day now. However, Spring is the main breeding season and for most species; whether building nests, laying eggs, incubating them, feeding nestlings or caring for fledglings, some part of their breeding programme usually occurs then. It simply makes sense, timing their offspring's fledging and dispersal into the population to fit the period of the year when most of their food is abundant. Depending on species, the birds' food can be flower nectar, fruit, insects or other smaller animals such as, well, young birds. And each species times its breeding period to fit their young fledging when their food is most abundant

I often find these birds in the woodlands when I am monitoring the Tawny Frogmouths,
and this pair were nesting in a small tree next to a Frogmouth nest tree
Insects are becoming more abundant every day as the weather warms up, although flying insects can be difficult to catch and often it is their larvae that are bigger and more nutritious than the adult forms, such as moth caterpillars. Butcherbirds catch most of their prey on the ground, like the big fat grub that this one caught.

All butcherbirds have hooked tips to their bills - for catching and holding prey efficiently
There is a reason for all bird behaviour and all bird anatomy. Evolution if driven by efficiency

But birds' bills are sensitive organs and the butcherbird thrust the food
deep into its chick's throat without the slightest bit of harm

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