Terrible photo, but you can see the orange underside which is pretty diagnostic.
The Swamp Wallaby (Wallabia bicolor) is a small macropod marsupial of eastern Australia. This wallaby is also commonly known as the Black Wallaby, with other names including Black-tailed Wallaby, Fern Wallaby, Black Pademelon, Stinker (in Queensland), and Black Stinker (in New South Wales). The Swamp Wallaby is currently the only living member of the genus Wallabia.