Cicadas are amazing creatures. A long life as an underground-dwelling nymph is followed by a wonderful transformation to adult winged treetop dweller. At the moment the air is alive with the sounds of cicadas. As I write this a Clanger (Psaltoda claripennis) is rattling and clanging away on a jacaranda tree on the footpath. Come twilight, the sound of traffic is completely drowned out by the rumbling drone of the Bladder Cicada (Cystosoma saundersii). In nearby eucalypt woodlands the roar of Razor Grinders, Cherrynoses and Double Drummers is truly overpowering.
These are the loudest insects on the planet. The Green Grocer, Yellow Monday and the Double Drummer produce noise intensity greater than 120dB at close range — a sound approaching the pain threshold of the human ear. A large Razor Grinder in full song can cause permanent hearing loss if held close to the human ear (great idea, eh?).
Entomologist Chris Burwell from the Queensland Museum explains cicada song in Wildlife of Greater Brisbane. Designed to attract females, the song of the male cicada unfortunately alerts predators, particularly birds, to its presence. As a result calling male cicadas usually take flight as soon as you approach them (making them quite hard to photgraph). Calling males often form huge groups, and there is evidence that this ‘wall of noise’ actually repels birds, because it is so painful to their ears!
Their interesting songs, striking appearance and sudden summer arrival (including their mysterious abandoned nymph cases) has brought these harmless insects lots of fans. As a child I marveled over the images of emerging cicadas by the astonishing Densey Clyne, and as a photographer always enjoyed trying to capture them on film – which can be quite challenging. Photographing the emergence of adults from the nymph stage is always fun. This happens under cover of night (although some species will emerge during the day).
While walking at Ravensboune National Park recently we stumbled upon this emerging adult cicada. After watching it for a while we concluded that it was stuck, and had been so for a few hours. Putting aside my ‘don’t interere with nature’ rule for a moment, I moved the insect up so that it could grab the branch. Over the next 20 minutes we were transfixed by the entire process – with unfolding wings and the changing body colour, a fascinating transformation.
You could write a book about cicadas! Wait up, someone already has. Australian Cicadas by Max Moulds is a wonderful book, a ‘must-have’ is you are interested in the biology and identification of these extraordinary insects.
Here are some great links for information about cicadas: