Since European settlement the forests of southeastern Australia have been broken up into disjunct islands by clearing. An important result has been the localized loss of some vertebrate fauna. The remaining mammal fauna is closely associated with forests with a dense understorey. In the long term, occasional high intensity wildfires in spring or summer encourage the growth of a dense understorey.

Some fire regimes, particularly frequent, low-intensity bums in autumn currently used in forest management, will reduce and eventually eliminate the dense understorey. As it is lost, many native mammal species will be disadvantaged and many exotic species will be advantaged.