Environment modification might be one reason that the so-called devil bird – understood for its relentless late-night breeding call – has actually ended up being more typical in Melbourne’s external suburban areas, according to scientists.
The koel, a migratory bird, generally shows up in Australia from Papua New Guinea and Indonesia to reproduce from late September to early October, when the male will sing his marketing call day and night to bring in a woman.
Jacinta Humphrey, who investigates metropolitan bird neighborhoods at La Trobe University, stated koels were practically never ever seen in Melbourne up until just recently and were more typical in New South Wales and Queensland.
“They used to be super rare in Melbourne, but now a lot of people report hearing them and they are hard to miss with their incessant calls throughout the night,” Humphrey stated.
“There hasn’t been a lot of research into why this is happening, but the general idea is that climate change may be involved.”
Birdlife Australia’s public affairs supervisor, Sean Dooley, stated there was no doubt koels were ending up being far more typical in Melbourne.
“I remember heading up to Fairfield Park by the Yarra River in 2000 to twitch what was about the sixth koel sighting on record in Victoria,” Dooley stated.
“That bird was perhaps the vanguard, as the records have really increased since then. Our Birdata monitoring website now has 750 records of the koel in Victoria.”
Dooley stated there were 121 tape-recorded sightings of koels in 2022, according to Birdlife Australia’s newest yearly bird count.
“This doesn’t necessarily mean there were 121 birds in the state, as their call is so loud that multiple counters may have heard the same bird,” he stated.
Michael Clarke, an emeritus teacher in zoology at La Trobe University, has actually been performing bird studies at Victoria’s many southerly point, Wilsons Promontory, for 17 years. He states koels, which are a cuckoo types, leave their eggs in the nests of other birds to feed them.
“In 2017 we got the first record of [koels] down there. There’s been another sighting this year … and that was noteworthy because the host, the red wattlebird, was noticeably abundant in my surveys,” Clarke stated.
“The number of sightings are going up and they are being detected more than they were in the past,” he stated. “They are clearly exploring territory that we have never seen before and what’s driving that is really puzzling.
“It may be a response to climate change, with places that were previously inhospitable to them now tolerable.
“The red wattle birds at Wilsons Promontory need to be alert to a parasitic species that will deposit an egg into their nest or sometimes raid it.”
Humphrey and Clarke both stated more research study was required to comprehend why koel migration paths were altering.
“They are a bird that is used to warmer temperatures and as things are slowly warming up in the southern parts of the country, they’re deciding that this habitat is suitable and they’ll keep travelling south where there are more resources,” Humphrey stated.
Dooley stated there might be other elements at play too, like a boost in food in Melbourne suburban areas and an abundance of host types, like wattlebirds.
“It’s definitely not due to birds moving our of their core natural range, as there has been an increase in numbers in Queensland and New South Wales,” he stated.
“There are a whole suite of east-coast rainforest birds like koels that are spreading south and west into Victoria. Most are fruit eaters, but not all.”