The buzzing of cicadas is as much a part of the Australian summer soundtrack as the sizzling of barbecues and the rumbling of suburban lawn mowers.
However their loud, cyclic calls can at times be unrelenting and are powerful enough to drive away predators, people and their pets.
But the insect’s mating song is a symphony to cicada enthusiast Dr Nathan Emery.
A self-confessed cicadaphile, he has recorded the insects at sound levels of up to 120 decibels.
“It can get painful for extended periods of listening,” Dr Emery told Jen Fleming on ABC Radio Sydney.
“To put that into perspective, that’s about the equivalent of a chainsaw in full running or a heavy metal concert.”
During the working week, Dr Emery is a scientific officer with the Australian Botanic Garden.
In his off time he can be found wandering Sydney’s woodlands searching for cicadas, with a sound level meter and insect net in hand.
The loudest broods he has encountered were in the Macarthur region in the city’s south-west.
“Species like the double drummer, the green grocer and the cherry nose, they’ve come out in large numbers this season.
“They’re making it very hard for us to have a normal conversation in the outdoors.”
An early fascination
Dr Emery’s interest in the invertebrates emerged during childhood trips to the bush with his father and siblings.
“We’d always have competitions amongst each other of who could catch the most cicadas and impress dad the most,” he said.
That passion never waned and today Dr Emery continues searching for answers about the noisy herbivores with the help of fellow ecologists and insect enthusiasts.
“Australia has the highest number of cicada species in the world, and it seems outrageous to me that we know little or nothing about their ecology.”
ABC Radio Sydney listeners shared their experiences of where they were hearing the insects this year.
“Two nights this week we’ve had to go inside from our back porch; the ears were ringing and painful from cicadas.” — Kathy from Haberfield
“The loudest cicadas by far are in the Blue Mountains. They’re 50 per cent bigger than the green grocers and are a motley brown bark camouflage colour.” — Kerry
“We’re in West Ryde and we have to close the doors to hear each other speak.” — Suzanne
“We went walking from Patonga to Woodbine. It was deafening, sounded like electrical high voltage.” — Neil
“The loudest cicadas are on the Bulli Pass on a hot morning.” — Kat
Citizen science opportunity
Dr Emery said studying cicada species could be difficult due to their periodic emergence patterns which required long-term data collection.
He has invited insect enthusiasts to help with his research and recently launched an online citizen science project called The Great Cicada Blitz.
Using photographs and sound recordings uploaded by the public, he is creating a detailed map of the different species found around Sydney.
He hopes the information will help monitor how environmental and climatic variations can trigger their emergence.
“They’re readily heard in the suburbs and everyone seems to have a story about cicadas from their childhood,” he said.
“I’m trying to rekindle that interest in cicadas for as many people as possible.”
Cicadas facts and numbers
- There are more than 350 identified cicada species around Australia but it is estimated there could be anywhere between 700 and 1,000.
- Young nymphs begin their lives underground, feeding on plant sap, before emerging as adults to breed.
- Cicadas can spend anywhere from four to 10 years underground before emerging, but some species are believed to have longer lifespans.
- Once above ground it is estimated cicadas live for between one and four weeks.
- Only male cicadas create the singing sound used for attracting mates.
- Their main predators are birds, but spiders, robber flies and brush-tailed possums have also been observed feeding on them.
- In the Sydney area cicadas start emerging in September through to the warmer months of the year.
- It is believed some cicada species emerge at prime number year intervals to avoid predation.
Source: Dr Nathan Emery