WATCH: Koalas attack each other in ugly brawl
A pair of territorial koalas have been filmed biting and screaming at each other in an ugly brawl.
Video of the two marsupials sitting in a tree shows a koala screaming as another one bites it from behind in a tree at Great Otway National Park in Victoria.
Onlookers seem intrigued by the interaction - one woman can be heard laughing, and another appears upset.
But the koala keeps biting its opponent, locking its jaw on the shoulder as it screams.
The biting continues, but much to the shock of onlookers the other koala fights back and bites the other koala's face. It nearly falls from the tree but manages to hang on before the video ends.
"We came across these two koala's fighting over territory in an eucalyptus tree," the video recorder said.
"The noise was horrible and sad to witness," she added.
It's not known exactly why the pair were fighting but it's possible they were fighting over territory.
Koalas live in complex social groups, according to the Australian Koala Foundation.
A dominant male koala can have 43 hectares, but that "home range" can overlap others.
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Even once the dominant male dies in their home range, it can take 12 months to for another koala to take that territory as their own.
Another explanation could be a mating ritual.
According to The Koala: Natural History, Conservation and Management, female koalas sometimes scream and fight off suitors. At times these screams will attract other males who will fight the suitor, and as a result, the female may choose the most dominant male from the conflict.
It's not the only time koalas have been seen brawling either.
In December, two koalas held up traffic in Adelaide Hills as they wrestled on the road.
