The Sound of the Australian Bush at Night

There are some sounds that instantly tell you where you are. Magpies warbling at dawn, cicadas screaming on a hot summer afternoon, kookaburras laughing from the trees. And for me, one of the great sounds of the Australian bush at night is the quiet, haunting call of a Boobook Owl: boo-book … boo-book. Or, as generations of Australians have also heard it, mopoke … mopoke.

The Australian Boobook (Ninox boobook) is our smallest and most widespread owl. Most of us are probably far more likely to hear than see one. By day they usually tuck themselves away in a leafy tree or hollow, then as darkness falls this compact little predator comes alive.

Its name has a wonderful story. “Boobook” is a Dharug word recorded from the Sydney region very early in the colonial period, around 1790. It’s one of those Aboriginal words that made its way into Australian English. Better still, the name is essentially the bird telling us what to call it. Boo-book. “Mopoke” is another Australian rendering of that same two-note call. Boobook, mopoke, morepork - people have been sitting around campfires and homesteads listening to this little owl calling from somewhere beyond the light and trying to put its voice into words for a very long time.

Don’t be fooled by the cute face, though. A Boobook might only be around 30 centimetres long, but it’s a formidable night hunter. Those enormous forward-facing eyes give it excellent depth perception, while facial feathers help channel sound towards its ears. Like other owls, the structure of its flight feathers suppresses the noise of air moving over its wings, making its approaches astonishingly quiet. From a perch it waits and watches for insects, mice, small birds and other prey, and it can even take bats on the wing.

This makes one of the threats facing Boobooks especially perverse. Owls are natural rodent controllers, but when we use anticoagulant rat poisons we can end up poisoning the predators that are doing the job for us. Poisoned rats and mice may remain alive and vulnerable for some time, making them easy prey for an owl. Australian research examining dead and dying Boobooks found rodenticide residues in nearly three-quarters of the birds tested, with about half containing levels considered potentially dangerous. So there’s a very simple lesson here: if you want an owl doing your pest control, don’t poison its dinner.

Boobooks also need something else that’s becoming increasingly scarce across Australia: old trees. They generally nest in hollows, and good hollows can take many decades, sometimes more than a century, to form. Those old, battered gums with broken limbs, scars and holes that can look “untidy” to us are prime real estate for Aussie wildlife. Owls, parrots, possums, gliders and bats all depend on them. Researchers have even recorded Boobooks competing with Brushtail Possums and cockatoos for scarce nesting hollows.

That’s why I get frustrated when mature habitat trees are treated as though they can simply be replaced by planting a sapling somewhere else. A new tree may be valuable, but it’s not ecologically equivalent to an old hollow-bearing tree. You can replace a tree on a landscaping plan. You cannot replace 150 years of habitat.

Boobooks are only one part of Australia’s extraordinary owl story. We also have Powerful Owls, Barking Owls, Masked Owls, Sooty Owls and Grass Owls, each adapted to a different part of the country and a different way of hunting. And just to clear up one of the great Australian birding misunderstandings: Tawny Frogmouths are not owls. They’re wonderful, nocturnal, beautifully camouflaged and suitably owl-like, but they are frogmouths and more closely related to Nightjars.

Looking at this photograph, though, it’s the sound that comes back to me. Somewhere beyond the campfire, somewhere down beside a creek line, somewhere among old gums beneath a huge Australian night sky: mopoke … mopoke.

It is a small sound from a small bird, but it carries an enormous sense of place. The Aussie bush after dark. Long may we hear it.

I photographed this gorgeous little bird in Alice Springs.