In some rare circumstances and for reasons unknown, groups of young male koala are known to gather together into a “bully” of koala. Groups comprising of up to 20 koala have been recorded. A bully of koala will often aggressively patrol their home territory and attempt to capture and attack other animals that they come across. They have been known to attack people. A couple, while hiking near Mt Bogong in Victoria, reported being woken up in their tent and viciously assaulted by a large group of young male koala.