I see this is an old thread, but the information is always useful.
One dangerous Aussie creature not mentioned here is the Magpie. That ubiquitous black and white bird that carols so beautifully in the mornings.
In springtime some nesting magpies become very aggressive and will swoop anyone who ventures into their territory. They can draw blood (I have had this happen, I had headphones in and was not aware of the bird until I felt a sharp pain on my head where it's beak had connected) and a few unfortunate people have lost eyes.
If you are caching anywhere with tall trees in the springtime Magpies may be a threat.
- Keep an eye and ear out. Maggies will usually give a familiar "dive bomb" call as they swoop. It's hard to describe this call, but pretty much anyone in Australia would be able to recognise it.
- If a magpie is swooping wave your hands in the air as it goes over. This will deter the immediate attack but some birds are persistent and will continue to swoop until you leave.
- Wear sunglasses to protect your eyes.
- A helmet or any kind of head protection is not a terrible idea.
- The best course of action if you find yourself in the territory of a cranky magpie is to leave the area and try again in a few weeks time once breeding season is over and the birds settle down.
