There are about 200 species of stick insects or phasmids found in Australia and more are discovered on a regular basis. They usually live high up in gum trees but after a stormy day you can find them trying to look inconspicuous in unlikely places. People have found stick insects hanging off their laundry drying in the sun, clinging to windows or on plants in your garden and more unfortunate ones, drowned in swimming pools. Stick insects have truly amazing camouflage and can be easily overlooked as they often stay unmoving for long periods. Australian stick insects range in size from a few centimeters to the longest species; the Titan Stick Insect, Acrophylla titan, which can grow up to 30cm from head to tail.
Once a phasmid believes that it has been seen there are a few tactics that they employ to avoid being eaten. Males can fly away when stressed, but females can’t escape predators so easily and will attempt to try to blend into the background of twigs and leaves, It will often, sway in a regular motion to help it blend in with its surroundings.
All phasmids begin life as an egg which is dropped from the end of the female’s abdomen and falls to the ground at the base of the tree or shrub. Thousands of eggs are laid during the females’ life. The Spiny Leaf Insect, Extatosoma tiaratum eggs have a knob, called a capitulum, which is attractive to ants. Ants will carry the eggs back to their underground nests, eat only the knob, and leave the rest of the egg safe in their nest, protected from other animals that might eat it. To avoid being detected after they hatch, the young spiny leaf phasmids (also known as nymphs) resemble, smell and behave like red-headed black ants. They emerge from the ant nest and climb rapidly upwards, looking for soft green leaves.
Many female phasmids do not need to mate in order to produce fertile egg, but the eggs produced will hatch into females. If the females do mate with a male before producing eggs, the nymphs (babies) may be male or female . Most females live for about 18 months, while the males are only short-lived, surviving for around 6-8 months. They are just one of the fascinating creatures that make up the wildlife in our local bush land. If you see any, take a photo and share it with us on our facebook page. Contacts: www.stillcreeklandcare.com.au email Stillcreeklandcare@iinet.net.au, Nick Chartorisky 9653 2056 or facebook Still- Creek-Landcare The Landcare Group for Galston, Arcadia, Berrilee and surrounding areas.