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
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
Herbert's Rock-wallaby
Petrogale herberti ('Herbert's rock-weasel')
Best place to see
Carnarvon Gorge National Park, Queensland
Herbert's Rock-wallaby is widespread and common. Unlike other Rock-wallabies it persists in small pockets of suitable habitat amongst cleared woodlands and can co-exist with the introduced red fox. The distribution abuts that of the Brush-tailed Rock-wallaby in the south and there is a narrow zone of hybridization between the species. Herbert's Rock-wallaby found well into the hinterland from the coast out to Clermont and Rubyvale to the west of Rockhampton.
Carnarvon Gorge dissects its way through the rugged ranges of Queensland’s central highlands. Carnarvon Gorge features tall sandstone cliffs, side gorges featuring remnant rainforest vegetation, endemic Cabbage Tree Palms (Livistona nitida) diverse riparian flora and grassy woodland, and equally diverse fauna and Aboriginal rock art. The Park is about 720 km northwest of Brisbane. To access Carnarvon Gorge National Park you need to travel to Roma or Emerald. From Roma, you need to drive 90 km north to Injune then a further 160 km along the Carnarvon Highway. From Emerald, you need to drive 65 km south to Springsure then 70 km east to Rolleston, and a further 61 km to the Carnarvon turnoff. Take not that the 44 km road to the park currently has 21 km of unsealed gravel surface. This road may become impassable after rain and is suitable for conventional vehicles and caravans in dry weather only. All-weather access is by 4 WD. The Park has camping at the vehicle-accessible day use area only during Queensland Easter, winter and spring school holidays. Walk-in camping (9.7 km trek) at the Big Bend camping area is available year-round. Accommodation can be found near the Park entrance at the Takarakka Bush Resort and Carnarvon Gorge Wilderness Lodge.
The Park has a large number of walking trails from the easy Baloon Cave Aboriginal cultural trail (1 km return) to the longer and more challenging Big Bend campground (19.4 km return).
Identification
Males to 6.0 kg and females to 4.3 kg. Herbert’s Rock-wallaby has long, dense fur with a coarse texture. The general dorsal colour from mid back to rump is grey-brown. The rump is rufous brown. Individual hairs have dark grey bases with a brown mid-band, with either a pale or black tip on the back, and a paler tip on the rump. The fur is longer towards the rump. From the face to between the ears is dark grey-brown and from the crown to the shoulder area the fur is a paler grey-brown. The nose is naked and black. There is an indistinct broad dark stripe from the nose through the eye to the base of the ear. The dark stripe is offset below by a broad white to pale buff stripe. A narrow black dorsal stripe begins between the eyes and reaches to the back of the head. The upper sides of the ears have a pale grey base and black tip. The posterior edge of the ear is yellow and the sparse hair inside the ear if a buff yellow. The shoulders are marked by is a large black patch that may extend some distance down the side, bounded by a pale-grey stripe that extends down the side. The arms and legs are grey-brown and the feet are dark brown to black. The hands, fingers and the toes are black. The base of the tail is yellow-brown with a paler underside. The remainder of the tail is black and the length of the hair increases towards the tip, so that the tail terminates with a prominent brush. Some individuals have a few white or pale-yellow hairs towards the tail tip. The throat and upper chest are slate-grey and the abdomen is pale yellow-brown. Many individuals have a central white throat patch, which is very small or extends in a blotchy manner to the chest. Occasionally there may be small white patches on the base of the inner thigh. The Herbert’s and Brush-tailed Rock-wallabies are indistinguishable in the zone where they come together and hybridise.
In the more northerly part of its range, Herbert's Rock-wallaby tends to be lighter and the dark dorsal stripe extends further down the back. The cheek strike is fainter but the white side stripe is prominent. The tail brush is more modest.
Habitat
In common with other Rock-wallabies, Herbert's Rock-wallaby inhabits boulder fields and rock-strewn slopes and outcrops. It is distinguished by resilience to urban and agricultural incursions and to foxes.
Foraging behaviour
The diet of Herbert's Rock-wallaby has not been studied. In general Rock-wallabies are opportunistic and generalist feeders eating mainly forbs and browse from shrubs and trees, some grass, and seasonal items like fruit, seeds, flowers and insect larvae in the tropics.
Reproductive behaviour
Herbert's Rock-wallaby is presumed to follow the reproductive pattern of other North Queensland Rock-wallabies. The best studied of these, the Allied Rock-wallaby, has an oestrus cycle of 29-34 d, post-partum oestrus, embryonic diapause, a pouch life of 6-7 months, with weaning at 11 months. Breeding is continuous but proportionally more young are born in the late Dry season than the Wet season.
Social organisation
Rock-wallabies are typically social and live in colonies varying from a few individuals to over 100. In the closely related Brush-tailed Rock-wallaby, females are philopatric (stay in natal home range) and so matrilines build up. Males disperse but do not necessarily leave the colony. Rocky day-time shelters are defended and used repetitively. Foraging ranges may overlap other individuals.
Further readings
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.