A water shortage has driven hordes of "bin chickens" into urban areas to feast upon garbage, according to a national bird count.
The white ibis, more commonly known as a "bin chicken", has made the top 10 most commonly-seen birds in BirdLife Australia's Aussie Backyard Bird Count for the first time.
A significant increase in the reporting of white ibis in urban areas saw the bird move from 13th spot in the 2018 list to 10th this year.
It's the first time the species has made the top 10 since the tally began in 2014.
BirdLife Australia spokesman Sean Dooley said the top three birds - the rainbow lorikeet, noisy miner and Australian magpie - remained unchanged but the addition of the white ibis to the top 10 highlighted the impact of drought.
Bin chickens would normally feed on a wide range of food including yabbies, worms, grasshoppers and crickets and their "natural stronghold" was the Murray-Darling Basin, Mr Dooley told AAP.
But after years of drought, the birds have been forced to find new environments to feed and breed.
This led them to the inner-city streets of Sydney, Brisbane and the Gold Coast, where their adaptability has seen them thrive.
"You have to admire their resilience and resourcefulness," Mr Dooley said on Wednesday.
"But it is disturbing at another level, because birds are basically a great indicator of what's going on in the environment.
"The fact we're not seeing them out in the Murray-Darling and other inland areas, where they traditionally would be, shows the disturbance we're having right across the country."
Mr Dooley said despite the increase in urban populations, the overall number of white Ibis is actually declining.
"The population is not going up, it's just shifting," he said.
"If anything the population is going down, like it is with a lot of waterbirds."
Mr Dooley said the white ibis - which is capable of travelling for thousands of kilometres - could return to its natural habitat if conditions improve.
"One of the remarkable things about Australian waterbirds is their ability to ride the boom-and-bust cycles," he said.
"This mysterious knack they have for knowing when conditions are good inland for them to go back and find enough food to raise the next generation."
More than 88,000 people took part in the 2019 bird count which saw almost 3.4 million birds registered over seven days in late October.
Australian Associated Press
