Invertebrates (animals without backbones) play a significant role in nature as decomposers, pollinators, and prey for many wildlife species - without them we would not see other larger species.
They are important food sources for many larger animals, such as birds, bats, frogs, lizards, bandicoots and quolls.
Invertebrates on the surface and within the ground play a vital role in decomposing leaf litter, branches, fallen timber and other organic matter as they use this as a food source. This recycles nutrients back into the soil and rejuvenates soil health and productivity.
Insects are very important in pollination so that vegetable crops, fruit set and flowers are much more abundant and successful. Bees are not solely responsible for this - butterflies, moths, ants, beetles, and native wasps are some of the many different types of insects which assist with pollination.
Creating or maintaining a diversity of insects and other invertebrates in your garden will achieve a natural balance reducing the risk of dominance of undesirable or destructive invertebrates, such as aphids, scale insects, or leaf-eating insects.
A note on spiders
Though you may have fears about them, spiders help maintain a natural balance in the garden. They eat insects and other invertebrates, and spiders in turn are eaten by birds and other animals.
Spider are particularly important for a number of bird species which depend on spider webs for successfully binding their nests - these include all robin species, Grey Fantails, Blackhead, Crescent and New Holland Honeyeaters, Tasmanian Thornbills and Brown Thornbills.
But, watch out for harmful spiders such as Red-backs or White-tailed spiders. They can cause painful, nasty bites.
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Illustration by Kris Schaffer