Kangaroos are marsupials and belong to the Family Macropodidae (i.e. big feet) that is grouped with the Potoroidae (potoroos, bettongs, rat-kangaroos) and Hypsiprymnodontidae (musky rat-kangaroo) in the Super-Family, Macropodoidea. This comprises around 50 species in
The Rock-wallabies (Petrogale spp.) is the most diverse genus amongst the living macropods with 16 species ranging from 1 to 12 kg in size. They are found across mainland Australia and on some recently separated offshore islands but not on the Bass Strait Islands, Tasmania or New Guinea. The species diversified from a common ancestor about 4 million years ago and their closest affinity to other macropods is with the Tree-kangaroos. Diversification of species occurred in two waves. The first gave rise to the Short-eared Rock-wallaby, the Monjon, the Narbelek, the Yellow-footed Rock-Wallaby and the Proserpine Rock-wallaby. The second was about a million years ago and lead to species that are not all morphologically distinctive like those along the Queensland seaboard. All Rock-wallabies favour habitat with rocky outcrops and slopes, cliffs and gorges or are found on boulder piles and escarpments especially in the wet-dry tropics. Their ability to scale precipitous rock faces in leaps that appear to defy gravity comes from adaptations to the feet and tail. The feet are short relative to the majority of macropods that inhabit flat ground. The pads are thick, spongy and highly granulated so that they compress on the rock surface and maximise grip. The tail is long and cylindrical with little taper and great flexibility. The tail acts as a counterbalance and rudder in rapid hopping across uneven surfaces and allows changes of direction in mid-air.
Cape York Rock-wallaby
Petrogale coenensis ('Coen rock-weasel')
Mungkan Kandju (Kaanju) National Park, Queensland
The Mungkan Kandju National Park is a large wilderness area (457, 000 hectares) between the Archer and Coen Rivers and includes part of the McIlwraith Range foothills. The Cape York Rock-wallaby is associated with the eastern side of Cape York but several populations are found around the township of Coen and so it is likely to be in this nearby National Park. The Park is only accessible by 4WD vehicle and is likely to be closed in the Wet season (austral summer). Coen is about 8-10 h drive from Cairns along the Peninsula Development Road. The ranger station at Rokeby is a further 1.5 -2 h drive to the west of Coen. Accommodation within the park is bush camping at several sites and so visitors need to be entirely self-sufficient. There are a limited number of bush tracks for driving and walking out from campsites is recommended taking into account that water bodies are inhabited by estuarine crocodiles. To orient yourself, Queensland National parks provides an excellent map of the Cape York National Parks.
Males to 5 kg and females to 4.2 kg. The Cape York Rock-Wallaby and Godman's Rock-wallaby are generally similar and share a number of external characteristics with the Unadorned and Allied Rock-wallaby. Most Cape York and Godman's Rock-wallabies are more yellow-brown on the limbs, head and around the base of the tail than any of the species. Godman’s rock wallaby has a faint dark stripe across the side to face beginning at the nose and passing through the eye to the base of the ear. This stripe is bordered by another indistinct yellowish one which is not always apparent. The Cape York Rock-wallaby tends towards the pale buff-coloured cheek-stripe. Both species have a central narrow dark brown stripe from about the eye level to the back of the head extending to the upper part of the back in the Cape York Rock-wallaby. The chest and belly are a sandy brown to greyish yellow. This is variable and one specimen had light underparts counter pointed by mottled brown. The distal third to half the tail is grey-white with a darker base. In some specimens the terminal part of the tail is silvery white. The density of hairs increases at the tail tip but there is little or no terminal brush.
The preferred habitat is open tropical woodland where rocky outcrops, ridges, gullies and seasonally dry creek beds are occupied. Shelter is sought amongst rocks and boulders often submerged in vine thickets. These rock-wallabies are only likely to be seen in late afternoon or evening when they emerge from such dense cover. Boulders are the main feature of this rock-wallaby's habitat with a vegetation of tall grasses, shrubs and a canopy of trees. Fire management to favour cattle grazing is a threat to this species as the timing and frequency of fires transforms ecosystems to grasslands. Such hot fires intrude destructively into the areas of high relief occupied by the rock-wallabies, and run wild with a fast and high intensity even though such habitat is of no value to cattle grazing.
The diet of the Cape York Rock-wallaby has not been studied but foraging occurs amongst the boulders of shelter habitat and out into adjacent woodland. They likely eat a variety of plant foods including herbage, browse, fruits and seeds.
Reproductive behaviour has not been studied.
The biology including behaviour of this species is largely unknown. The declaration of national parks encompassing its habitat may provide an impetus and opportunity for much needed research.
Clancy TF, Close RL (1997) The Queensland rock-wallabies. An overview of their conservation status, threats and management. Australian Mammalogy 19, 169-174.
Eldridge MDB, Close RL (1992) Taxonomy of rock wallabies, Petrogale (Marsupialia: Macropodidae). I. A revision of the eastern Petrogale with the description of three new species. Australian Journal Of Zoology 40, 605-625.
Eldridge MDB, Close RL (1997) Chromosomes and evolution in rock-wallabies, Petrogale (Marsupialia: Macropodidae). Australian Mammalogy 19, 123-135.
Eldridge MDB, Moore LA, Close RL (2008). Cape York Rock-Wallaby. In The Mammals of Australia 3rd Edition (Van Dyck S, Strahan R eds.) pp. 368-369. (Reed New Holland, Chatswood).