Koalas are very good swimmers.

Koalas prefer to stay relatively close to their home range where they feel comfortable.

The closest relative to the koala is the wombat. It is believed that the two shared the same ancestors 25 million years ago.

The word Koala is an Aboriginal word for “no drink”. Whilst they obtain quite a lot of moisture from the eucalypt leaves, it is a myth that they don’t drink at all.

Koalas will not eat any leaves, regardless of their age, that contain less than 55% water.

Sources:
http://www.infogunnedah.com.au/tourism/koalas_facts.php
Jackson, Stephen. Koala : Origins of an Icon. Belmont: Allen & Unwin, 2008.