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Autumn weather supports a variety of wildlife for observation in our backyards and other natural habitats. The emergence of adult flies, caterpillars, millipedes and all the critters that live in the leaf litter are abundant in the rainy, windy months of the year.

Here are some of the most common enquiries we recieve for animal identification and explanations of animal behaviour.

Solider Fly

The female of this species of soldier fly, Boreoides subulatus, is wingless.This fly is often referred to as a "walk", due to its lack of wings. The adult males do have wings but they are much smaller than the females.

They start their lives in compost and soil, emerging as adults when autumn rains come. At that time they climb tree-trunks, walls and fences, where they are found by the winged males.

What is the benifit of being a fly with out wings?

The females being wingless allows them to be bigger and not fill their bodies with wing muscles so more of their bulk can be devoted to producing eggs.

Flying is over rated for them as there is lots of rotten logs ( their prefered habitat) they can simply walk over to.

The males are much smaller and so can fly easily, howerer, they are still capable of impregnating the larger females and spreading the species gene around.

The most common time of year for sightings of this fly is Autumn.

Wingless soldier fly
Female wingless soldier fly, Boreoides subulatus. Image: Maggie Crowley
© Australian Museum

Saw fly larva

There are about 200 known species of Sawfly in Australia. Sawfly larvae is the common name given to larvae of various species of wasps. They have 3 pairs of true legs, and up to 8 pairs of prolegs

Gum Tree Sawfly larvae
"These grubs were on some eucalypt trees down near our creek. I thought they were caterpillars but, when we looked them up on the internet, we found they were not. They are funny - when you bump the leaf they all stick their tails in the air." Image: Yazmin Tresize
© Yazmin Tresize

Sawfly larvae are not true Caterpillars, but are the larvae of various species of wasps, or more accurately Symphyta. They have 3 pairs of true legs, and up to 8 pairs of prolegs


The Autum months see the Portugese millipede, the most common animal in Australian suburban gardens emerge from their summer underground to roam above the surface. It is the autum rains and the first growth of winter grasses that signal their return.

Most millipedes are long, thin, segmented invertebrates, with two legs to each body segment. Millipedes wil curl up if disturbed. They are usually found in moist places such as under logs, rocks and in leaf litter. In gardens of any size these myriapods can be encountered under cushions, pot plants, rocks and washing baskets.

Millipedes feed on vegetable matter, leaf litter, moss, roots, new petals and leaves.

Some species can produce fluids that stain the skin, but they do not bite or possess a sting.

In wet weather, millipedes have been reported swarming in large numbers, and sometimes enter houses. The prefered habitat is damp and light.


Centipedes are long slender invertebrates with many pairs of legs, one per body segment. There are over 125 species in Australia.

Centipedes are primarily predators, feeding on insects, snails and worms and other smaller centipedes.

The first set of legs are modified claws with venom glands. The rearmost pair of legs are set backwards and are used for fighting off predators and holding prey.

Bites to humans usually cause little more than pain and swelling. Centipedes are usually found in damp leaf litter, under rocks and logs, and in compost heaps. They sometimes enter houses, especially after heavy rains have disturbed them from the garden.

Centipede, can be a fierce predator. Image: M Bulbert
© Australian Museum


Many species of moths and butterflies are in the caterpillar stage of their life cycle in the autumn months. They are very active in backyards, gardens and bushland habitats.

The different stages of the life cycle give few clues as to what the appearence is in the other stages.

See if you can spot any of these caterpillars in your backyard. Are they native or introduced? Friend or foe?