There are, however, bucketloads of animals and plants that will cause inconvenience. I know this, because I've encountered them all. Numerous times.
The leeches are lively at the moment. They lurk in leaf litter and on low vegetation, waiting for a meal to pass by. Most often, that meal is a pademelon, but sometimes that meal is me.
These leeches (family Haemadipsidae) have two cutting jaws, which leave a characteristic wound pattern. (On my heel.) Other families of blood-feeding leeches, such as the medicinal leech, have three jaws that make a Y-shaped incision. A large number of species are jawless and either insert a needle-sharp proboscis into their victim or swallow their prey whole. Fortunately, in the latter case, their prey is usually small, soft-bodied and spineless.
They might turn up anywhere. This one was resting on the garden hose, looking as though it might be digesting a gutful of macropod blood. (Anterior to the right.)