A home range is the place where a koala spends all its time, and encompasses all the resources the koala requires to survive and reproduce. In healthy koala habitats, koalas do not have to compete for resources – so competition for food trees and other resources influences how koalas are distributed across a landscape.
A home range represents the perfect balance, the minimum that a singular koala needs.
There can be some stable overlapping of home ranges as koalas do interact, especially in mating season. Koala joeys spend the first 22-24 months with their mothers, at which time joeys leave the mother’s home range. Koalas do this to ensure that inbreeding does not occur, taking their genes out of their parent’s home range. Some joeys have been tracked as far away as 60km away from their mothers.
When koala habitats are destroyed by the removal of food trees and disconnected by roads and fences, the balance of the home range is destroyed. Very sadly, koala habitat is removed every day. Spotter catchers are hired to remove koalas to make way for new developments, but generally the koalas are translocated too close to where they were moved from, and the koalas come back to their home range and get injured, often fatally, by bulldozers. Some have called this approach a soft cull – to be blunt, we might as well be shooting the koalas.
To stop such koalas deaths, we need to learn from koalas, and we have to start understanding home ranges as a representation of balance. Koalas do have complex social structures and they have incredible powers of navigation – for koalas it’s about pathways, moving around from tree to tree – these movements provide the social cues, and we can create our communities around these cues. By allowing koalas to teach us, we can plan better urban developments, and where possible, we need to repair koala habitats that have already been damaged.
To learn more about koala home ranges: a study by Bill Ellis, Sean Fitzgibbon and team.