Name: Antilopine wallaroo (Osphranter antilopinus)
Size: Excluding their tails, which are about 65-100 cm long, males are 80-120 cm (head and body) and 18-50 kg. Females are 65-80 cm (head and body) and 14-25 kg.
Diet: They feed largely on grasses but occasionally forbs (herbaceous flowering plants) as well.
Habitat/range: Patchily distributed within savanna woodlands and forests spanning North Queensland, the Northern Territory, and Kimberley region of Western Australia.
Conservation status: Least Concern (IUCN).
Superpower/fun fact: The adult males could be described as the Arnold Schwarzeneggers of the savannas, putting on serious muscle mass as they grow throughout life.
Let’s cut straight to the chase, if not Australia’s best mammal, the antilopine wallaroo is certainly Australia’s most magnificent macropod*.
This herbivorous, largely grass-eating species is found across the tropical savannas and tall open forests of monsoonal northern Australia. Unlike two closely related species – the common wallaroo (O. robustus) and black wallaroo (O. bernardus) – the antilopine wallaroo largely avoids particularly rocky areas and escarpments, preferring flatter and more gently undulating habitat.
Antilopines are rather sociable and are commonly found with companions. Their group sizes typically range from 2-8 individuals and occasionally they can be found in large mobs of 20 or more. This may be related to localised, high-quality feeding areas or preferring safety in numbers as a way to avoid being a dingo’s dinner.
Antilopine wallaroos display a behavioural phenomenon known as sexual segregation, whereby all-male or all-female groups are common following the short breeding season that centres around the wet season (~December to March), when savanna grasses are most lush and abundant. We don’t really know why this behaviour occurs, but it may be related to different ecological and physiological pressures on males and females.
During the long dry season (~April to November) – when most adult females are carrying young (joeys) in their pouches – ‘bachelor groups’ of adult males spend much of their time slugging and kicking it out, deciding a dominance hierarchy and who the ‘top roo’ is. Large dominant males – which put your average gym junkie to shame – are seriously jacked, growing continually, and piling on muscle throughout their lives.
Matching their impressive macropodid muscles, antilopine wallaroos seriously rock savanna sartorial splendour. Males, which are much larger than females, are red-tan on top and cream-ish on their underside. Their forepaws and hindfeet have dark black tips. Females are greyer throughout, but it’s their ears that really pop, with distinct white fringing. Males and females both have prominent ‘swollen’ noses, due to enlarged nasal chambers that help with evaporative cooling in the hot and humid tropical conditions.
Hop to it and vote for your favourite savanna-dweller, the antilopine wallaroo, it’s the discerning choice.
*Full disclosure, I spent several years of my life studying and falling in love with antilopine wallaroos and savannas as part of my PhD research, but it’s scientifically proven antilopine wallaroos are the best macropods.
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Originally published by Cosmos as Antilopine wallaroo: the Arnold Schwarzenegger of the savannas
Euan Ritchie
Euan Ritchie is an applied ecology and conservation researcher at Deakin University. He has been fascinated by Australia’s mammals for as long as he can remember, and has been researching their ecology and conservation across this continent for over two decades. He tweets at @EuanRitchie1.
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