Mulligans Flat has long been recognised as one of the best bird watching sites in the ACT by the Canberra Ornithologists Group. The area is also rich in frogs, reptiles, invertebrates and mammals. It includes many rare and uncommon species such as red-necked and swamp wallabies, sugar gliders, black shingle-backed lizards, regent honey-eaters, and the spotted burrowing frog. Mulligans Flat is a relatively low lying area with grassland, woodland and open forest.