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 genus Macropus includes not only the large kangaroos but a range of mid-sized macropods known collectively at wallabies or brush wallabies. The exception is the Swamp Wallaby which is in its own genus Wallabia by virtue of its different chromosome number and other features. With the advent of agriculture and pastoralism the wallabies have fared less well than the kangaroos with most species in reduced ranges since European settlement. One species, the Toolache Wallaby (Macropus greyi) is extinct. In this pattern of range contraction, the Swamp Wallaby, is again an exception as it remains reasonably abundant in many peri-urban parks and reserves.

The Wallabies like the larger Kangaroos are predominantly grazers but may take some browse, especially the Swamp Wallaby. They share a similar body form and habits to the larger Kangaroos and are sympatric with Grey Kangaroos or the Antilopine Wallaroo in the north.

Species

Kwoora (Western Brush) Wallaby

Macropus irma

Best place to see

Dryandra Woodland, Western Australia

Dryandra Woodland is 164 km southeast of Perth and is a haven for threatened mammal species through circumstance and design via the Barna Mia animal sanctuary. Here you can find free-ranging Western Brush Wallabies along with Woylies (Brush-tailed Bettongs), Western Grey Kangaroos and Tammar Wallabies. The Sanctuary includes Banded Hare-wallabies, Rufous Hare-wallabies and Boodies (Burrowing Bettongs) for breeding and release in extensive re-introduction programs in Western Australia. The Woodland is best known for another marsupial, the Numbat.

Accommodation is available in cabins and there is a well-serviced camping ground.

Identification

The Western Brush Wallaby in common with the Tammar Wallaby shows sexual dimorphism.  The weight range of mature individuals is 7-9 kg. The back has a thick, soft fur which is blue-grey in colour. It is layered with a long grey outer fur and pale red inner fur that shows through on the sides. The face has a pale yellow cheek stripe with a black top to the head and ears. There is a black stripe down the back. The striking feature of this wallaby is its jet black forepaws and toes contrasting against the grey limbs and pale grey underside tinged with yellow or red. They also have a distinctive crest of black hairs on the terminal two-thirds of the tail. Western Brush Wallabies are easily distinguished from the Western Grey Kangaroo by their small size, the Tammar Wallaby by the their distinct black fore-paws, and the Bettongs by their smaller body size.

Habitat

The Western Brush Wallaby's range has contracted with agricultural settlement. They are found in open forest and woodland and forage on seasonally wet flats and depressions with low grasses. Shelter is found in thickets of scrub. They also inhabit mallee, heath land and Karri forest.

Foraging behaviour

Predominantly grazers with some browse in the diet. In Whiteman Park, Perth, they ate about 31% monocotyledons including the dominant lawn grass and 69% dicotyledons. The most common plant in the diet was a cycad, Macrozamia riedlei. Choice amongst the two plant groups was about in proportion to availability suggesting a generalist diet.  They will graze into the daylight and so are more easily seen than other wallabies and bettongs which are more strictly nocturnal. They do have unusual dentition with short and relatively small molars and slender lower incisors. The dietary significance of this dentition is yet to be thoroughly researched.

Reproductive behaviour

The reproductive biology of the Western Brush Wallaby is poorly studied. Breeding may be seasonal with births between April-May and permanent emergence from the pouch 6-7 months later in October-November.

Social organisation

Solitary in daytime shelters but aggregate on pasture at night. They are usually seen alone or in small groups of two such as a mother and her young-at-foot or a female consorting with a male.

Further readings

Wann JM, Bell DT (1997) Dietary preferences of the black-gloved wallaby (Macropus irma) and the western grey kangaroo (M. fuliginosus) in Whiteman Park, Perth, Western Australia. Journal of the Royal Society of Western Australia 80, 55-62.