Antilopine wallaroos are sometimes referred to as a kangaroo or antilopine kangaroos.
Before fighting, males make an audible hiss as an alarm. This is usually followed by a foot thump. Males also perform a “head tossing” motion before fighting.
Communication Channels: visual ; tactile ; acoustic
Perception Channels: visual ; tactile ; chemical
Although populations of antilopine wallarooos are decreasing, the species is classified of least concern by the IUCN. This species has likely benefited from human conversion of land to agricultural and grassland areas.
US Federal List: no special status
CITES: no special status
IUCN Red List of Threatened Species: least concern
Because both species graze in grasslands, Antilopine wallaroos may compete with cattle.
Antilopine wallaroos are hunted by the Aboriginal people of Australia.
Positive Impacts: food
Antilopine wallaroos consume a variety of grasses and act as hosts for mites, nematodes, fleas, and ticks.
Antilopine wallaroos are herbivorous, and their diet is mainly composed of grass. They seek areas with short grass, like low tussock grass, or where tall grass has been burnt and reduced to shoots.
Plant Foods: leaves
Primary Diet: herbivore (Folivore )
Antilopine wallaroos inhabit savanna woodlands throughout the northern, tropical regions of Australia, from the Kimberley to the Gulf of Carpentaria. They are also found in the Cape York Peninsula.
Biogeographic Regions: australian
Other Geographic Terms: island endemic
Antilopine wallaroos inhabit the savanna woodlands of Australia. During the day they reside in shaded wooded areas to avoid the hot sun. At dusk they graze in grasslands and at dawn return to wooded areas. During the cooler wet season, antilopine wallaroos may also graze during the day, but they seek shelter from rain in wooded areas. Eastern populations may be found on slopes and tops of small hills. They may also be found in valleys and low-lying depressions on the floodplains of major rivers, especially in moist areas populated with short green grass. Northern populations favor sites with permanent water where fires occur late in the season.
Habitat Regions: tropical ; terrestrial
Terrestrial Biomes: savanna or grassland ; forest
Little information is available regarding the average lifespan of antilopine wallaroos. The longest lived antilopine wallaroo in the wild was 16 years of age, while the longest lived antilopine wallaroo in captivity was 15.9 years of age.
Range lifespan
Status: wild: 16 (high) years.
Range lifespan
Status: captivity: 15.9 (high) years.
Male and female antilopine wallaroos are very sexually dimorphic. Adult males are usually a reddish tan color. Females, however, are brownish tan in the back and hind parts and usually have gray heads and shoulders. Females also have white tips on the back of their ears. Paws and feet of both sexes are white on the ventral side and are black tipped. Adult males have a distinct swelling of the nose above the nostrils that is possibly used for cooling. Males are also much larger than the females, reaching up to 70 kg. A female of this species ranges from 15 kg to 30 kg. Females develop their pouches after about 20 months. In joeys, the fur coloration is apparent after 6 to 7 months. The shape of a female joey’s head is more petite than the male joey’s.
Range mass: 15 to 70 kg.
Range length: 1.5 to 1.9 m.
Sexual Dimorphism: male larger; sexes colored or patterned differently; male more colorful; ornamentation
Other Physical Features: endothermic ; bilateral symmetry
There are no known predators of antilopine wallaroos other than humans.
Known Predators:
An increased amount of fighting by male antilopine wallaroos has been observed near the beginning of the breeding season. To attract a mate, a male sniffs the female’s cloacal region, then shows his ventral surface and erect penis.
Male antilopine wallaroos reach sexual maturity at 2 years of age, whereas females reach sexual maturity at 16 months and develop their pouch after 20 months. Females come into estrous within a few days of each other. Although estrous of females does not seem to be related to the age of their young (joeys), estrous always occurs after the permanent emergence of the joey. Gestation lasts about 35 days.
Only one offspring is produced per breeding season. After birth the neonate climbs into the mother's pouch, much like all macropods. After about 20 weeks, the joey begins to emerge from the pouch. At about 6 months the joey completely comes out of the pouch for the first time, and at about 37 weeks the mother does not allow the joey back in the pouch. A joey is gradually weaned, feeding less and less from its mother until about 15 months after birth.
Breeding interval: Antilopine wallaroos breed once yearly with births during the wet season.
Breeding season: Mating of antilopine wallaroos occurs at the beginning of the wet season, usually around December.
Average number of offspring: 1.
Range gestation period: 34.1 to 35.9 days.
Average weaning age: 15 months.
Average time to independence: 15 months.
Range age at sexual or reproductive maturity (female): 16 to 20 months.
Average age at sexual or reproductive maturity (female): 16 months.
Average age at sexual or reproductive maturity (male): 2 years.
Key Reproductive Features: seasonal breeding ; gonochoric/gonochoristic/dioecious (sexes separate); sexual ; fertilization ; viviparous
Male antilopine wallaroos lose interest in their mate and young once the neonate reaches its mother's pouch. Once all neonates reach their mother's pouch, the group sexually segregates; large males form small groups while females and young remain together in large groups. Even after weaning, young antilopine wallaroos maintain a close relationship with their mother, resting together and grooming each other.
Parental Investment: female parental care ; pre-hatching/birth (Provisioning: Female, Protecting: Female); pre-weaning/fledging (Provisioning: Female, Protecting: Female); post-independence association with parents
The antilopine kangaroo (Osphranter antilopinus),[3] also known as the antilopine wallaroo or the antilopine wallaby, is a species of macropod found in northern Australia: in Cape York Peninsula in Queensland, the Top End of the Northern Territory, and the Kimberley region of Western Australia. It is a locally common, gregarious grazer.
The description of the species by John Gould was published in 1842, one of four new species of 'kangaroos' presented before the Zoological Society of London in 1841. The type location was given as Port Essington. The author assigned the new species to the genus Osphranter,[2] a taxon later submerged as a subgenus of Macropus, and recognised an affinity with his earlier description of Macropus robustus (known as the common wallaroo or euro).[4] A taxonomic restructuring in 2019, based on genetic analysis,[5] promoted Osphranter back to genus level, redefining the antilopine kangaroo and the red kangaroo, among others, as species within the genus Osphranter.[3]
The common names of the species include antilopine wallaroo, antilopine kangaroo and antilopine wallaby.[4] The specific epithet antilopinus was proposed by Gould for the resemblance of the fur to the African mammals known as antelopes.[2] The descriptive "antilopine" or "antelope" kangaroo is sometimes substituted as the 'antilopine wallaroo', but in behaviour and habitat it is similar to the red, eastern grey and western grey kangaroos. Occupying a similar niche to the large and reddish Osphranter rufus in the woodlands of southern and eastern Australia, it is also referred to locally as the red kangaroo, though it is a different species.[6]
The antilopine kangaroo is a larger species of Osphranter, a genus of kangaroos and wallabies. They share many characteristics with others of the genus, but have longer and more slender limbs like the larger species of the genus.[6] The fur is short, pale at the ventral side and grading to a reddish tan colour over the upper parts of the pelage. Females have similar coloration, although lighter and with greyish fur at the head and shoulders. A patch or stripe of paler coloured fur is seen at the lower part of the head, and a lighter colour at the inside and edge of the ear sharply contrasts with the darker fur colour of outer side. The paws of the front and hind legs are very dark, and contrast the lighter fur of the lower limb. Their tails are thickly covered in fur, a uniform width along its length, and a paler shade of the upper body colour. The bare skin of the rhinarium is black.[7]
Measurements of the head and body combined is up to 1.2 metres for males, with a tail to 900 mm, and no longer than 840 mm for females, whose tails are up to 700 mm. Their standing height, from the crown of the head to the ground, is approximately 1.1 metres. The female may weigh up to 20 kilograms, and males may be over twice this weight at 49 kg.[7]
The male's head shape, like the red kangaroo Osphranter rufus, resembles that of a mule. The antilopine kangaroo is one of a few macropods to display sexual dimorphism, with the male being mostly a reddish colour above, and females being considerably greyer. It is one of the largest macropods, being only slightly smaller than the red kangaroo and the eastern grey kangaroo (Macropus giganteus).[7]
Osphranter antilopinus forms social groupings whose males assert hierarchical dominance over one another. The numbers of each group may be up to 30 individuals, but these may be separate groups assembling as a response to threats from humans or dingoes. The animal may be observed as individuals or with one or two others of the species, although these are assumed to indicate that others are in the immediate area. Seasonal rainy periods induce them to feed during the day or night, but foraging activity is restricted to later parts of the day in the dry seasons. The species is observed with other macropods, often congregating around a waterhole, in the Top End with Osphranter bernardus (the black wallaroo) or more commonly with Osphranter robustus erubescens (the euro) that is also found on open eucalypt woodlands near rocky hills.[6] Communication amongst the individuals includes a hissing sound, given as an alarm, a guttural coughing noise, and a softer cluck uttered by females to their young and when males are soliciting a mate. The species also produces a thumping sound with the foot to alert others to danger.[7]
Breeding may occur at any time of the year, although births tend to be timed to precede the beginning of the north's wet season.[7]
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The distribution range extends inland from the northern coast of the continent, from the Kimberley region in Western Australia across the Top End and narrowly extending to a wider range at tropical regions at the east of Cape York. The population in Queensland is geographically isolated from others by an environmental barrier below the gulf of Carpentaria, and a second and third clade are weakly distinguishable in the Northern Territory and Kimberley.[8]
The habitat preferred by O. antilopinus is tropical, with perennial grasses providing forage, in vegetation occurring over lower hills and plains.[7] The grasslands of its habitat are found in association with monsoonal eucalypts, as open or regenerating woodlands, or as the dominant vegetation of unwooded plains. They are only found at altitudes less than 500 metres. The species is locally common in parts of the wide range, but these groups occur in a patchy distribution within this area.[1]
This widely distributed and presumably numerous species is listed as least concern by the IUCN, noting that, while the population is assessed as declining, it did not meet the criteria of vulnerable to extinction. The Red List recommends that monitoring of the population be undertaken. In some locations where it was common, local populations of O. antilopinus are known to have declined. Presumed threats to the species include the increase in pastoralist use of the land, with alterations to the fire ecology and hunting being possible factors influencing the species' trajectory.[1]
The antilopine kangaroo (Osphranter antilopinus), also known as the antilopine wallaroo or the antilopine wallaby, is a species of macropod found in northern Australia: in Cape York Peninsula in Queensland, the Top End of the Northern Territory, and the Kimberley region of Western Australia. It is a locally common, gregarious grazer.
