The common wallaroo (''Osphranter robustus''), also known as the euro, hill wallaroo, or simply wallaroo,
[ is a species of macropod. The word ''euro'' is particularly applied to one subspecies (''O. r. erubescens'').][WE Poole and JC Merchant (1987): ''Reproduction in Captive Wallaroos - the Eastern Wallaroo, Macropus-Robustus-Robustus, the Euro, Macropus-Robustus-Erubescens and the Antilopine Wallaroo, Macropus-Antilopinus.'' Australian Wildlife Research 14(3) 225 - 242]
online link
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The eastern wallaroo is mostly nocturnal
Nocturnality is an animal behavior characterized by being active during the night and sleeping during the day. The common adjective is "nocturnal", versus diurnal meaning the opposite.
Nocturnal creatures generally have highly developed sens ...
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
Sexual dimorphism is the condition where the sexes of the same animal and/or plant species exhibit different morphological characteristics, particularly characteristics not directly involved in reproduction. The condition occurs in most ani ...
, like most wallaroo
Wallaroo is a common name for several species of moderately large macropods, intermediate in size between the kangaroos and the wallabies. The word "wallaroo" is from the Dharug ''walaru'', and not a portmanteau of the words "kangaroo" and "wal ...
s.
Subspecies
There are four subspecies:
*the eastern wallaroo (''O. r. robustus'') – found in eastern Australia; males of this subspecies have dark grey fur, almost resembling the black wallaroo
The black wallaroo (''Osphranter bernardus''), also known as Woodward's wallaroo, is a species of macropod restricted to a small, mountainous area in Arnhem Land, Northern Territory, Australia, between South Alligator River and Nabarlek. It clas ...
(''Osphranter bernardus''). Females are lighter, being almost sandy in colour.[
*the euro or western wallaroo (''O. r. erubescens'') – found covering most of the species' remaining range to the west; this subspecies is variable, but mostly brownish, in colour.][
*the Barrow Island wallaroo (''O. r. isabellinus'') – this subspecies is restricted to ]Barrow Island Barrow Island may refer to:
* Barrow Island (Western Australia), Australia
* Barrow Island (Queensland), Australia
* Barrow Island, Barrow-in-Furness
Barrow Island is an area and electoral ward of Barrow-in-Furness, Cumbria, England. Origina ...
in Western Australia
Western Australia (commonly abbreviated as WA) is a state of Australia occupying the western percent of the land area of Australia excluding external territories. It is bounded by the Indian Ocean to the north and west, the Southern Ocean to th ...
and is comparatively small. It is uniformly reddish-brown.[
*the Kimberley wallaroo (''O. r. woodwardi'') – this subspecies is found in the ]Kimberley region of Western Australia
The Kimberley is the northernmost of the nine regions of Western Australia. It is bordered on the west by the Indian Ocean, on the north by the Timor Sea, on the south by the Great Sandy and Tanami deserts in the region of the Pilbara, an ...
and in a band roaming through the Northern Territory
The Northern Territory (commonly abbreviated as NT; formally the Northern Territory of Australia) is an states and territories of Australia, Australian territory in the central and central northern regions of Australia. The Northern Territory ...
. It is the palest of the four 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 large 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 (''O. r. robustus'') — which is dark grey in colour — occupies the eastern slopes of the Great Dividing Range
The Great Dividing Range, also known as the East Australian Cordillera or the Eastern Highlands, is a cordillera system in eastern Australia consisting of an expansive collection of mountain ranges, plateaus and rolling hills, that runs rough ...
, and the euro (''O. r. erubescens'') — which is mostly brownish 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 period lasts 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 their 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 (''O. r. isabellinus'') is classified as vulnerable.
Taxonomy
In 2019, a reassessment of macropod taxonomy determined that the species should be moved from the genus ''Macropus
''Macropus'' is a marsupial genus in the family Macropodidae. It has two extant species of large terrestrial kangaroos. The term is derived from the Ancient Greek μάκρος, ''makros'' "long" and πους, ''pous'' "foot". Thirteen known exti ...
'' to the genus ''Osphranter
''Osphranter'' is a genus of large marsupials in the family Macropodidae, commonly known as kangaroos and wallaroos (among other species). It contains the largest extant marsupial, the red kangaroo (''O. rufus'').
In 2019, a reassessment of mac ...
''. This change was accepted by the Australian Faunal Directory
The Australian Faunal Directory (AFD) is an online catalogue of taxonomic and biological information on all animal species known to occur within Australia. It is a program of the Department of Climate Change, Energy, the Environment and Water of th ...
in 2020.
References
External links
Animal Diversity Web
Photos at ARKive.
{{Taxonbar, from=Q691473
Macropods
Mammals of Western Australia
Mammals of South Australia
Mammals of the Northern Territory
Mammals of New South Wales
Mammals of Queensland
Mammals of Victoria (Australia)
Marsupials of Australia
Mammals described in 1841
Taxobox binomials not recognized by IUCN