Extract from The Guardian
These are massive, charismatic birds with an exhibitionistic streak who have increasingly moved to the city with their natural habitat under pressure
The Guardian/BirdLife Australia 2021 bird of the year poll begins on Monday
Last modified on Sun 26 Sep 2021 06.01 AEST
For the past several months, I’ve kept a slightly uneasy vigil on a pair of breeding powerful owls in inner Brisbane, just a couple of kilometres from home. In that time they’ve seen off crowds of curious onlookers, and a determined eviction attempt by sulphur-crested cockatoos, to raise one confident and healthy-looking chick, which will remain dependent on them for several more months yet.
After that, it faces a much bigger challenge: finding and establishing its own territory and mate.
Powerful owls have a lot going for them. They’re massive, charismatic birds and a perennial Guardian Australia Bird of the Year contender. They’ve proven resilient and relatively adaptable. Natural denizens of tall eucalypt forests in south-eastern Australia, they have changed their foraging habits and moved into the suburbs of Sydney, Melbourne and Brisbane, where the pickings – especially hyper-abundant ring-tailed possums – are easy.
But they’re also on the edge. Although classed as secure federally, they’re listed as vulnerable in New South Wales and Queensland, and endangered in Victoria. As apex predators, they hold large territories and need big, old-growth trees with hollows about the size of a wheelie bin to breed in. For this diminishing resource, they compete with other species including cockatoos and brush-tailed possums, as well as with each other.
As much of their natural habitat has been cleared (or razed by megafires in the Black Summer of 2020–2021), and once-favoured prey items such as greater gliders have declined in numbers, powerful owls are increasingly dependent on remnants of suburban bushland for their survival. In our cities, they face other threats: vehicle strikes, secondary poisoning from rodenticides and excessive human disturbance.
My local pair was particularly public. Between May and August, the male roosted daily in a tree over a bike path. From there, he surveyed a constant procession of bicycles, walkers and their dogs while his mate incubated and brooded her chick in an adjacent tree. When the chick became too big for her to comfortably share the hollow with, she joined him over the path, over which they left a conspicuous wash of scat and vomited up pellets of indigestible remains.
Powerful owls are increasingly dependent on remnants of suburban bushland for their survival. Photograph: Dr Nick Hamilton
They became local celebrities, and well habituated to human presence. Powerful owls mate for life, and this was one loved-up pair: at dusk, they’d preen each other’s faces before separating to hunt. On one occasion, they were seen enthusiastically copulating, despite having a six-week old owlet. There was loud squealing, both from the owls and a small handful of lucky observers. New parents could only admire their energy levels.
One breeding female she was aware of in Melbourne had become so unnerved by constant disturbance from visitors that she began swooping. “I’d never, in all the years I’d worked with powerful owls, been swooped before,” she says. “I was out of there, because I didn’t want to be adding that extra stress.” John White, an associate professor in wildlife ecology at Deakin University, says powerful owls are “softies, with a slight anger management side”.
That is polite code for saying that you really, really do not want to get swooped by a powerful owl. Usually, you’ll get no more than a glare. But David Hollands, who first published the photographic volume Birds of the Night in 1991, gives a visceral account of one researcher who was forced to flee under sustained bombardment by a particularly cranky male. He was left with a talon injury up one nostril.
Such encounters are fortunately rare. “It is kind of a double-edged sword. If someone cares about something, they are more likely to take steps to protect it,” Isaac says. “It is good that people care about them, but we do have to limit our impact to the environment that they’re relying on, and also try not to cause those shifts in behaviour.”
But the bigger potential problem is the longer-term bottleneck in the species’ population. As I’ve watched the chick thrive under the care of its parents, I’ve often wondered: where will it go when it’s time to move on? “One of the big gaps in the research for powerful owls is we don’t often know what happens to the chicks,” Isaac says. “We don’t know the fate of the chicks, or where they end up.”
And that’s where people who love powerful owls might help. If you live in Sydney, Melbourne or Brisbane, you can volunteer for BirdLife Australia’s powerful owl project and report your observations. And of course, you should vote for it in Bird of the Year. It’s the Incredible Hulk of Australian birds – a gentle giant with an exhibitionistic streak. Just don’t make them angry. You won’t like them when they’re angry.
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