The common wallaroo or wallaroo, also known as the euro or hill wallaroo is a species of macropod. The word euro is particularly applied to one subspecies. The eastern wallaroo is mostly nocturnal and solitary, and is one of the more common macropods. It makes a loud hissing noise and some of the other subspecies are sexually dimorphic, like most wallaroos.
Subspecies
There are four subspecies of the common wallaroo:
eastern wallaroo – Found in eastern Australia, males of this subspecies have dark fur, almost resembling the black wallaroo. Females are lighter, being almost sandy in colour.
euro – Found covering most of the species' remaining range, this subspecies is variable, but mostly brownish, in colour.
Barrow Island wallaroo – This subspecies is restricted to Barrow Island in Western Australia, and is comparatively small. It is uniformly reddish-brown.
Kimberley wallaroo – This subspecies is found in the Kimberley region of Western Australia and in a band roaming through the Northern Territory. It is the palest subspecies and is a dull brown-grey colour. Kunwinjku of western Arnhem Land call this subspecies ngabudj. They also have separate names for male and female, galkibard and wallaar, respectively. A big male is called ganduki. This animal manages well in areas without permanent water and on a diet of nutrient-poor grasses, but it does need shelter.
The eastern wallaroo — which is grey in colour — occupies the eastern slopes of the Great Dividing Range and the euro — which is rufous in colour — occupies the land westward.
Reproduction
Wallaroos are not a type of animal that has one or two mating seasons throughout the year, but rather females can give birth at any time during the year. Through a process called embryonic diapause they are able to get pregnant any time after giving birth, but the embryo does not start to develop until the previous joey is able to leave the pouch of the mother. Wallaroos are also polygynous, which means that the males can have multiple female partners. During the mating process, fighting occurs between males to attract a female. The fights normally do not end in one of the two wallaroos dying, but rather the two males will fight until one surrenders. The gestation periodlasts around 30 to 38 days, after which the young joey travels into the mother's pouch where it suckles and develops. The young joeys start to leave the pouch at around six months and by nine months they no longer spend most of their time in the pouch. Male wallaroos are fully developed at around 18 to 20 months; females are fully developed at around 14 to 24 months. The relationship with the joey and his parents changes as the joey grows and gets older. During the time in which the joey is in the pouch, the father stays around to protect the joey and mother from predators, but once this protection is no longer needed the relationship weakens between the two. After the joey no longer needs its mother for food, it still maintains a close relationship with her.
Status
The eastern wallaroo as a subspecies is not considered to be threatened, but the Barrow Island subspecies is classified as vulnerable.
Taxonomy
In 2019, a reassessment of macropod taxonomy determined that the species should be moved from the genus Macropus to the genus Osphranter. This change was accepted by the Australian Faunal Directory in 2020.
