Much of the wildlife is threatened by introduced species and weeds . However , the eucalyptus wooded savannah , tropical rainforests , and other types of habitat are now recognized as being globally important . Although the land is mostly flat and about half of the area is used for grazing cattle , and wildlife is threatened by introduced species and weeds , the relatively undisturbed eucalyptus wooded savannahs , tropical rainforests and other types of habitat are now recognized for their global environmental significance .