Image: Image by Beverly Buckley from Pixabay
Sydney residents are grappling with a major fly infestation, as large swarms have been spotted across streets, homes, and public spaces across the city.
The fly surge is mainly due to a mild winter and unusually warm spring temperatures, which have created ideal conditions for the population to thrive.
However, experts suggest the fly population will eventually subside as conditions change.
Expert Explains Fly Surge
Dr Thomas White, an evolutionary ecologist and entomologist at the University of Sydney, told City Hub that the increased presence of flies was “very typical” at this time of the year.
Dr White explained that the recent surge in fly numbers was mostly due to the “relatively mild, warm conditions we’ve experienced over winter” which resulted in good survival prospects for eggs and/or larvae.
“Then coupled with the recent spell of warm and humid weather to kick off spring means their development has picked up once more, and we get the large burst of adults all emerging at once like we’re seeing”, Dr White said.
Dr White quelled concerns about the long-term impact of flies, stating that while it might “(rightly) feel intense now, fly numbers will begin to taper off in the coming weeks as they always do.”
A silver lining to the fly surge is the boost it provides to local insect-eating wildlife, including birds and lizards, which depend on insects as a food source.
“Temperature plays a crucial role in the life cycle of a fly, from eggs to larvae, pupae, and adulthood, contributing to the rapid growth of the fly population in these conditions,” Dr White said.
Pest Expert Predicts Fly Infestation Will Persist Until Next Year
Julian Bracewell from Pest2Kill, a Sydney based pest, mentioned that the fly infestation has been ongoing for several months and is expected to continue until at least autumn or winter next year.
“You always see an increase in moths, butterflies, flies, and mosquitoes around springtime because it’s hot and humid, and it’s when plants and organic life flourish,” Bracewell told news.com.au.
He explained that the combination of El Niño and early rising temperatures has made the fly problem especially severe this year.
“It’s unprecedented. August was hotter than ever … the world is getting warmer so the issue shows no sign of slowing down.”
Last year, a heatwave swept across Australia, and in September, temperature records were broken once again. Parts of southern and central NSW recorded scorching highs, including 34°C in Wollongong and 36°C at Sydney Airport.
Bracewell expressed that the situation was so poor that his company had seen a marked increase in fly-related services this spring, with calls coming in from as far as the Hunter Valley.
Professor Nigel Andrew, an expert in Entomology from Southern Cross University, told City Hub that the flies are “definitely enjoying the warmer weather after all the spring rain.”
“Its perfect conditions for them to emerge. They do really well with these conditions. Last year they were also in high numbers. They will stick around as long as the weather conditions stay warm and wet. Different species may come and go through late spring and summer,” Professor Andrew said.
The flies will eventually dwindle as temperatures drop and seasonal changes take effect.
