General information

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 Australia and a dozen or more in New Guinea.  Some of the smaller species, such as Yellow-footed Rock-Wallabies, Burrowing Bettongs, accompanied Pig-footed and Golden Bandicoots, Bilbies and possibly Hairy-nosed Wombats into extinction with the advent of pastoralism. However, the largest species remain in much of their original range with the grey kangaroos expanding inland as grazing habitat increased and coastal habitat was lost in clearance for agriculture. The defining feature of the kangaroo family is that they are the largest vertebrates to hop (both currently and from what we know from palaeontology).

 

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.

Species

Yellow-footed Rock-wallaby (South Australia & New South Wales)

Petrogale xanthopus celeris ('yellow-footed rock-weasel')

Best place to see

Brachina Gorge, Flinders Ranges National Park, South Australia

The Flinders Ranges National Park is about 450 km north-west of Adelaide. The 95,000-ha Park is located between the townships of Hawker and Blinman. The visitors centre is in Wilpena Pound. The campground at Wilpena has full facilities with powered sites, toilets, showers, fuel, phone, ATM, internet access, store, swimming pool, bar and restaurant. There is also the Wilpena Pound Resort which offers motel, chalet and self-contained units.

Brachina Gorge is an important refuge for the Yellow-footed Rock-wallaby and they are readily seen on the slopes of the gorge before twilight. The Gorge is traversed by 20 km self-guided vehicle trail that interprets 130 million years of geological history. The trail is best travelled from east to west, commencing at the Brachina Gorge/Blinman Road north of Wilpena Pound. A geological map and more detailed information on the Brachina Gorge Geological Trail is available from the Wilpena Pound Visitor Centre. The Gorge has a number of bush camp sites with pit toilets and fireplaces.

Identification

Individuals weigh up to 12 kg in a weight range of 6-12 kg. The Yellow-footed Rock-Wallaby has long, soft and silky fur emerging from a dense and dark grey underfur. The back is grey.  The face and crown of the head are grey with a yellow wash.  The white cheek strike is well defined and offset by a black streak running anteriorly from the eye.  The ears are long and yellow and highlighted at the base of the inner sides by a white edging.  There is a well-defined black dorsal stripe that runs from between the ears to the middle of the back.  The sides are strikingly marked.  A triangular brown patch behind the elbow is bordered by a white lateral streak that runs down the body to the hip.  A second brown patch tops the knee and is bounded by a white patch.  The abdomen is white and the arms, legs and feet are a uniform yellow.  The end fingers and toes terminate in brown.  The tail is particularly striking and has alternating bands of dark brown and yellow that becomes a uniform brown towards the tip. The tail terminates in a well defined crest of black hairs.  The entire underside of the tail is brown-white.

Habitat

To be added

Foraging behaviour

 

Reproductive behaviour

 

Social organisation

 

Further readings

Blumstein DT, Daniel JC, Evans CS (2001) Yellow-Footed Rock-Wallaby Group Size Effects Reflect A Trade-Off. Ethology 107, 655-664.

Copley PB, Alexander PJ (1997) Overview of the status of Rock-wallabies in South Australia. Australian Mammalogy 19, 153-162.

Copley PB, Robinson AC (1983) Studies on the Yellow-footed Rock-Wallaby, Petrogale xanthopus Gray (Marsupialia: Macropodidae) - II. Diet. Australian Wildlife Research 10, 63-79.

Dawson TJ, Ellis BA (1979) Comparison of the diets of yellow-footed rock-wallabies and sympatric herbivores in western New South Wales. Australian Wildlife Research 6, 245-254.

Eldridge MDB, Close RL (1997) Chromosomes and evolution in rock-wallabies, Petrogale (Marsupialia: Macropodidae). Australian Mammalogy 19, 123-135.

Robinson AC, Lim L, Canty PD, Jenkins RB, Macdonald CA (1994) Studies of the yellow-footed rock-wallaby, Petrogale xanthopus Gray (Marsupialia: Macropodidae). Population studies at Middle Gorge, South Australia. Wildlife Research 21, 473-481.