Drop bear

A dropbear or drop bear is a fictitious Australian marsupial. Drop bears are commonly said to be unusually large, vicious, carnivorous marsupials related to koalas (although the koala is not a bear) that inhabit treetops and attack their prey by dropping onto their heads from above.

They are an example of local lore intended to frighten and confuse outsiders and amuse locals, similar to the jackalope, hoop snake, or wild haggis. Stories of attacks by the fictional animal are commonly told to scare tourists.

Various methods suggested to deter drop bear attacks include placing forks in the hair, having Vegemite or toothpaste spread behind the ears or in the armpits, urinating on oneself, and only speaking English in an Australian accent

https://en.wikipedia.org/wiki/Drop_bear

Danger to humans and first aid
Bush walkers have been known to be 'dropped on' by drop bears, resulting in injury including mainly lacerations and occasionally bites. Most attacks are considered accidental and there are no reports of incidents being fatal.

There are some suggested folk remedies that are said to act as a repellent to Drop Bears, these include having forks in the hair or Vegemite or toothpaste spread behind the ears. There is no evidence to suggest that any such repellents work.

- See more at: http://australianmuseum.net.au/drop-bear - Australian Museum. It has to be true.