Gold Coast ibises are nesting above crocodile enclosures and beside the busy M1 to avoid animal control officers, an environmental consultant says.
Environmental consult Phil Shaw said part of managing the Australian white ibis population (Threskiornis molucca) includes collecting nests and eggs from key breeding locations to break the reproductive cycle.
"They're very smart," he said.
"They've worked out that if they go to places where there's a flying fox camp, or next to the road where it's really difficult for us to get to … they're kind of protected and they know they can keep breeding."
The managing director of Ecosure said ibises on the Gold Coast have even resorted to breeding inside enclosures at Currumbin Wildlife Sanctuary and Fleay's Wildlife Park.
"They've actually bred above the crocodile enclosures," he said.
Tipping point
The birds are also nesting beside the Pacific Highway at Elanora and Beenleigh, north of the Gold Coast, where they regularly fall victim to vehicle strikes.
Mr Shaw said he had been helping to manage the Gold Coast's ibis population since 1996, when it became overabundant.
On December 24, 1995 an airline disaster was narrowly avoided when a two-kilogram ibis flew into the engine of a Qantas Airbus A300 as it was was taking off from Coolangatta Airport.
"The pilot had to abort the takeoff and pulled up just in time at the end of the runway," Mr Shaw said.
Savants of the scrounge
About 2,500 ibises are estimated to live on the Gold Coast, down from the 5,000 inhabiting the city in the 1990s.
"The population was heading through exponential growth up to around 10,000," Mr Shaw said.
"So the management plan was designed to bring the population back to somewhere between 1,500 and 2,500 and we've been very successful at keeping it around that mark."
He said the population spike was driven by the availability of food.
"They get the food primarily from landfills, where the rubbish dumps provide the food from people throwing out their rubbish," he said.
"We estimate that 70 per cent of the population gets their food from that source.
Bum rap?
Griffith University Emeritus professor Darryl Jones said white ibises – also referred to as "bin chickens" or "tip turkeys" – played an important role.
"They primarily eat insects," he said.
"They get hammered with some unfortunate names, but they used to be called 'the farmer's friends' because they were the first animals that would turn up during a plague of locusts.
"They're a waterbird, or, strictly speaking, they're a mudflats bird — they poke those long black bills into the mud and get crabs and worms."
Mr Shaw said it was the ibises' ability to scavenge from bins and landfill sites tended to muscle other native birds out of habitats.
"They can get to all of the best nesting sites first and they push out the cormorants and the egrets and other native bird species," he said.
Mr Shaw said ibises had even resorted to breeding on the ground, on isolated islands and in Gold Coast resorts.
"They like palm trees," he said.
