Why are koalas more susceptible to extinction due to feeding behaviors?

Koalas are specialist feeders, living in eucalyptus trees and eating only a few types of gum leaves from which they get all nutrients and water requirements. They also occasionally eat the gum tree blossoms.

While there are hundreds of different eucalyptus species in Australia, koalas eat from only about 60 of the species, consuming about half a kilogram of eucalyptus leaves every day. Koalas will not eat all types of eucalyptus, feeding on just 14 species as their primary food source, specifically, the subgenus Symphyomyrphus.

Specialist species are often more prone to extinction because they rely on such a limited range of food. However, in the case of the koala, this is not what may eventually lead to their extinction. Dogs and cars pose a far greater threat, as koalas walk along the ground to travel between trees in their home range, and this is when they are at their most vulnerable.