For millions of years, the koala has adapted to its environment. In recent centuries, however, human activities have resulted in some deleterious situations with regard to the koala. On the one hand, various human activities have greatly reduced population levels in some areas. During the early twentieth century, the koala was nearly hunted to extinction. Although the population has recovered, there continue to be threats due to habitat loss, attacks from feral and domestic animals, and disease. Since the koala requires large areas of healthy, connected forest, the increasing human population has cut these corridors through agricultural, recreational, and business development.
On the other hand, in some areas, such as certain islands, the introduction of koalas has lead to "pest" populations, since they thrive in the absence of predators and competition.
Humans stand in a special role as stewards of creation. In this capacity, they have protected the koala in recent years, allowing once-threatened population levels to improve. On the other hand, they are trying various means to reduce numbers in areas where the koalas are pests.