Dropbears (Phascolarctos stirtouri) are the more vicious, carnivorous relative of the Koala Bear (Phascolarctos cinereus), whom they very closely resemble. They are generally slightly larger than the average Koala, and some specimens have been reported to grow as large as the extinct Giant Koala (Phascolarctos stirtoni).

They differ from the average Koala in several aspects. Firstly, they have a more aggressive temperament. Secondly, their hindquarters are heavier, with the pelvis bone being extremely dense. And lastly, their primary diet is meat, supplemented by tree leaves.

These features have combined to lead to an interesting passive-aggressive hunting method. The Dropbear will wait in a suitable tree, looking like an ordinary Koala Bear. When a suitable animal passes beneath it, it will drop from the tree onto the head of the animal, momentarily stunning its prey with its rather dense posterior. The Dropbear will then endeavour to disable its prey, by grabbing on with its rear claws, and slashing out the eyes and throat with its front claws. If, as usually happens, the Dropbear stuns the animal from the fall but falls off immediately afterwards, it will quickly switch tactics and attempt to hamstring the animal's rear legs with its front claws.

Having stopped the animal from escaping (too quickly), the Dropbear will then attempt scoop out the animal's intestines, using its claws to hold onto the animal's midsection. The Dropbear is fairly fast over short distances (20m), but it is usually content to amble after the stricken animal until the animal collapses from its initial injuries.

This attack is usually successful, however sometimes the Dropbear's poor vision in daylight means that it misses the prey animal altogether, the sound of the Dropbear's impact with the ground startling the animal out of the Dropbear's visual range. Smell and Hearing, on the other hand, are very acute.

Whilst attacks by the Dropbear on Humans are rare, they are usually fatal owing to the nature of the initial attack, and the Dropbear's preference for single victims. Many bushwalkers have reported close encounters with Dropbears, usually along the lines of 'and the cute Koala fell right out of its tree; I was so frightened I ran away'. These bushwalkers rarely know how lucky they are to have survived.

It is recommended that Bushwalkers wear a sturdy hat, and put on sunscreen and/or Aeroguard. Dropbears do not appear to like the smell of most sunscreens or Aeroguard, and a good hat (NOT tied around the neck) has been reported as being invaluable when the Dropbear lands and grips. Bushwalkers should be prepared to run away immediately after the sound of an impact, and to drop their pack as a decoy against the Dropbear chasing after them.