Christmas Beetles! The season is the reasonPosted: December 13, 2012
By Kim Pullen – Australian National Insect Collection
Christmas beetles, the quintessential insect of the summer festive season, have arrived.
Sporting their resplendent burnished bronze backs under the summer sun, these bulky creatures home in on the tops of gum trees with their loud whirring and clumsily try to grab a foothold, often only to tumble down and get up again for another try.
By the time you see a Christmas beetle, it’s nearly at the end of its life. It has already spent almost a year in the soil as a grub, eating organic matter, grass roots and possibly the finer surface roots of gum trees. In times of drought in south-eastern Australia, a grub may be forced to stretch out its life cycle and go another whole year in the soil!
A swarm of Christmas beetles can eat a lot of leaves, but they are not usually worth trying to control—the beetles you manage to get rid of one day will probably just be replaced by others the next. And in any case, the infestation does not last long.
In the ‘State of Origin’ of Christmas beetle colours, the Queenslanders hold the title. The Christmas beetles familiar to Victorians and New South Welshpeople (that’s a word right?) may be pretty, but they don’t compare to their tropical Queensland cousins. The Queensland rainforest dwellers come in smooth gold, pitted dark green, violet and even a mysterious iridescent opal with mauve reflections. The shifting colours are structural, coming not from pigments but from multilayer reflectors built into the hard shell of the beetle—more on this here.
This Queesland enthusiast has photographed a whole range of colours among his local Chrissy beetles.
So enjoy your Christmas beetles this year and tune in to Insect of the Week again next year for many more tales from the Insect world.