Hollow-using native mammals include possums and gliders, carnivorous marsupials, microbats and rats. It is believed that 83 diferent Australian native mammal species use tree hollows.
Mammals that can often be found using nest boxes include Brushtail Possums, Ringtail Possums, Sugar Gliders, Squirrel Gliders, several different species of Antechinus, and all species of Microbats.
Did you know that possums, gliders and antechinus (small mouse-sized carnivorous marsupial) will use numerous tree hollows for sleeping and to raise young, rather than just a single hollow? Most species are found to use between 2-9 hollows, but some species may use many more if available.
Here are some figures for the number of different hollows that individuals of various species of mammal will use in their home range: Ringtail Possum up to 5 hollows, Sugar Glider up to 5 hollows, Brushtail Possum between 4 to 18 hollows, Brown Antechinus up to 3 hollows, Brush-tail Phascagale between 27-38 hollows.
References: Tree Hollows and Wildlife Conservation in Australia; Nest boxes for Wildlife: a practical guide.