The main cicada season doesn’t really start until the chorus cicadas (Amphisalta zealandica) come out after Christmas, but two weeks ago, we found a few chirping cicadas (Amphisalta strepitans) on the rocks around Okains Bay.
Cicadas are largish, as insects go, but they’re well camouflaged. Usually, you find them by sound. As with most insects, it’s the males that do the singing. The main part of a cicada’s song is made by flexing plates (tymbals) on top of the body. Built-in amplifiers (opercula) pump up the volume to an astonishing level. Cicadas are noisy. I don’t know if any of the New Zealand species have been tested, but the calls of some North American cicadas are over 105 decibels at a distance of 50 cm. That’s nearly as loud as a rock concert (115 decibels). When the chorus cicadas here in New Zealand come out in large numbers, they can be so loud in some places that it’s impossible to carry on a conversation.
Some New Zealand cicadas add an extra feature to their song—a bit of drumming called clapping. The cicada snaps the leading edge of its wings against a branch to make a sharp click. Females also clap, and I’ve read (though I’ve never tried it) that you can call the males to you by snapping your fingers.
There are about 2500 species of cicada worldwide. Because of their size and volume, they seem to be culturally important wherever they live. They are eaten as food in many areas, and sometimes used as fish bait. Growing up, my siblings and I used to collect the shed exoskeletons of cicadas and attach them to our clothing like jewellery. When I lived in Panama, the children would catch cicadas and tie strings to their feet, then carry them like helium balloons, flying on the end of the string.
Wherever they live, they mark the seasons. Here in New Zealand, and in America where I grew up, summer hasn’t really started until the cicadas sing.
Loud singing? Drumming? Must be a summer rock concert!