These little brown birds, seen flitting around woodlands and occasionally my garden, are clever architects whose nest deceives potential predators.
I discovered this after I chose to write a piece on the yellow-rumped thornbill for the Bimblebox 153 Birds Project—a conservation meets art project highlighting the bird species recorded in Bimblebox Nature Refuge in Queensland, which is under threat from a proposed coal mine.
Yellow-rumped thornbills build a dome-shaped nest, where they lay their eggs. But they don’t stop there. On top of the dome, they add a second storey shaped like a classic cup nest.
Because this ‘nest’ is empty, it discourages potential predators from visiting to find the eggs and chicks, which are in the real nest below. Experimental studies have shown that a decoy nest does indeed reduce predation.
The trick nest may also help hide the real one from cuckoos, although not completely: the thornbills sometimes find themselves raising young shining bronze cuckoos.
Yellow-rumped thornbills (Acanthiza chrysorrhoa) are endemic to Australia and widespread, particularly across southern Australia.
The Bimblebox 153 Birds Project still needs writers for some of their bird species – would you like to write a short piece on the rufous whistler, black falcon or darter? See the full list still available at http://bimbleboxartproject.wordpress.com/2014/09/21/writers-needed-for-bimblebox-153-birds/
The completed exhibition, of written and spoken texts, art and music, will be exhibited to raise awareness of the campaign to save Bimblebox Nature Reserve.
Image: David Cook via Flickr (CC BY-NC 2.0).