Pied currawong
Pied currawongs form long-term pair bonds that extend across many seasons.
Article and images by Dr Julie O'Connor, senior conservation partnerships officer, Sunshine Coast Council
Australia is a nation of bird lovers but not all birds are loved equally it seems. For example, a delightful superb fairy-wren seems a lot more lovable than the pied currawong who snatches the wren from its nest, tears it apart then feeds it to its own young.
In 1941, one writer to the Melbourne Advocate penned of the pied currawong:
…Spring comes to light the gullies,
And currawongs to feed –
Stream-lined, querulous,
Anxious-voiced with greed.
Bird of shallow merit
With catchpenny cry,
your darkling flock inherits
the Summer’s panoply…
Not everyone, however, had such a jaded view of the currawong. A different perspective was offered in the Corowa Free Press in May 1944:
It may not be generally known that the currawongs – those big black birds
which visit at this time of year – are edible, and make a very tasty dish.
Currawong soup, or roast currawong, or currawong pie are all favoured.
At the present time roast currawong and mushrooms would be a highly
appealing meal. There are no coupons required for currawongs either.
OK, I really tried my hardest to find a love poem about currawongs, but not a single one was to be found. The currawong pie came the closest.
It appears we really do have a complex relationship with these impressive birds. And it's a complexity that is only increasing as ecosystem changes favour the currawong’s fortune over that of some other birds.
On Australia’s east coast, pied currawongs have traditionally been altitudinal migrants, moving to the coastal lowlands during autumn/winter, then returning to the ranges to breed in spring. In recent years, however, many pairs are choosing to stay on the coast to breed, a fact that must make many small birds very nervous.
A quick search of the scientific literature reveals no fewer than 27 native birds fall prey to pied currawongs. That being said, a 2001 study identified that common introduced birds were more at risk than common native birds. While that would certainly be dependent on the species available in a given area, predation of common starlings, European blackbirds, domestic pigeons, spotted doves, house sparrows, common mynas and red-whiskered bulbuls has been recorded.
Given that pied currawongs are native and co-evolved with their native prey, what has changed? Why such an impact now?
Well, we are largely responsible. Pied currawongs love the fruit of weed species that we have planted in our gardens, such as privet, lantana, camphor laurel and many more.
Despite thousands of currawongs being shot in the early 20th century for their role in spreading prickly pear and raiding agricultural crops, one study reported a population increase across Australia from three million in the 1960s to six million 30 years later.
Like many birds, they are monogamous, but unlike many species that only remain paired for a season, currawongs form long-term pair bonds that extend across many seasons. Nest building, incubation and brooding is undertaken by the female while the male supplies her with food and territorial defence during that time.
Both sexes contribute to the raising of young and an area of around 8 hectares is usually maintained to raise one brood per year.
The currawong’s diet consists primarily of fruit and insects but, as discussed, it also includes vertebrates (mainly birds).
Ornithologist, Colin Harrison, describes the pied currawong as having “the slightly furtive but alert air of a bird about to commit a crime.” Certainly the ‘crime’ of sustained predation on localised populations of small birds has the potential to be significant over time. One of the currawong’s prey species, the superb fairy-wren, can fledge three broods per year but in the event of predation may lay up to eight clutches to achieve that. Local populations of scarlet and eastern yellow robins in the New England area were in decline until pied currawong control was implemented.
Of course, there are a few winners in all this. Numbers of channel-billed cuckoos, which parasitise pied currawong nests appear to be on the rise. Brown snakes, carpet pythons and lace monitors are all known predators of pied currawongs.
In urban and other highly modified environments, populations of many native species can fluctuate wildly in response to the conditions we create. This is just part of the contemporary urban wildlife fabric. Remember, while currawongs may be snatching the occasional nestling to feed their own babies, they are also eating stick insects that defoliate eucalypts and prising lawn grubs from manicured lawns.
Oh, and by the way, pied currawongs are protected under the Nature Conservation Act 1992 in Queensland, so if you’re thinking currawong and mushroom pie sounds quite tasty, you might want to omit the currawong.
References
- Bayley, K. L. & Blumstein, D. T. 2001. Pied currawongs and the decline of native birds, Emu 101 199-204
- Debus, S. J. S. 2006. The role of intense nest predation in the decline of scarlet robins and eastern yellow robins in remnant woodlands near Armidale, New South Wales, Pacific Conservation Biology, 12 (4): 279-287.
- Harrison, C. 1988. Birds of Australia, Bison Books Ltd, London
- Low, T. 2017. The New Nature: winners and losers in wild Australia, Penguin Random House Australia.
- Prawiradilaga, D. M. 1996. Foraging ecology of pied currawongs Strepera graculina in recently colonised areas of their range, PhD thesis, Australian National University.
- Wood, K. A. 2000. Notes on feeding habits of the pied currawong Strepera graculina at Woollongong, NSW. Australian Birdwatcher 18, 259-266