Common Wallaroo

## Description

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 ).

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.

## Appearance

The Common wallaroo is a kangaroo of a rather stocky build, with coarse, shaggy fur, no hair on its muzzle, a relatively short and thick tail, and a characteristic upright hopping style. Its robust body shape, having shorter limbs than other species of kangaroo, may be an adaptation due to leaping around on rocks, with short, broad hind feet which have roughened soles for extra grip. The male can be up to twice the females size, with particularly thick-set forearms and shoulders.

## Distribution

The Common wallaroo can be found throughout most of Australia, except Tasmania. It usually lives on rocky hills, caves and rock formations with large overhangs, that can provide shade during the day. It also shelters in shrubland along streams, near their main sources of food and water.

## Behavior

Common wallaroos are mostly solitary and nocturnal, and occupy a relatively small and stable home range close to water or a rocky outcrop, and moving from rough country to feed on shrubs and grasses in adjacent areas. Small groups will sometimes form around valued resources, but these are usually quite loose as regards size and composition. These animals move by hopping on their huge hind legs, moving to new feeding areas that are within their home range. Male wallaroos sometimes fight or "box" with each other, mostly using their powerful feet for kick-boxing until one contestant gives way. Males display dominance like this in order to maintain social hierarchy or gain access to females to mate with. Common wallaroos all interact with each other by grooming, although this behavior is more common between joeys and their mothers.

## Diet

Common wallaroos are herbivorous, grazing mostly on shrubs and soft-textured grasses.

## Reproduction

Common wallaroos are polygynous, which means that one male mates with multiple females. To attract a mate, a male displays his dominance to other male wallaroos through frequent fighting, as well as displaying themselves for the females to see. Wallaroos mate throughout the year. A single joey is born after gestation lasting 30 to 38 days, then the tiny animal must climb up through its mothers fur into her pouch, where it can be nursed. The baby stays in its mother's pouch for protection and feeding and remains inside full time until it is 6 months old. It may occasionally fall out of the pouch, but quickly climbing back in. Weaning usually takes place around the age of 15 to 16 months. The mother waits until weaning before she mates again. Males are usually sexually mature at 18 to 19 months old and females at 22 months old.

## Population

### Population threats

The Common wallaroo is faced with no major threats, although it is legally killed in some areas for skins and food, and as a result of alleged damage to crops and pastures. It is estimated to comprise only around three percent of the total commercial kangaroo quota. The Barrow Island euro subspecies, which lives on Barrow Island, suffers from fatalities on roads and habitat degradation due to the development of oilfields.

### Population number

According to the Australian Government Department of the Environment, the total number of the Common wallaroo is 4,383,203 individuals, including 1,800 individuals of the Common wallaroo subspecies from Barrow Island. Common wallaroos’ numbers are stable today and they are classified as least concern (LC) on the IUCN Red List.

### Ecological niche

Common wallaroos, through their grazing, help disperse seeds within their ecosystem.

## Fun Facts for Kids

The word wallaroo combines (both in word and meaning) the words wallaby and kangaroo.

The common wallaroo can survive harsh conditions by sheltering in caves and rocky outcrops and can last as long as two or three months without drinking, existing just solely on the water in food plants.

In a process called embryonic diapause, the female wallaroo can become pregnant again soon after giving birth. The new embryo stays dormant until the older joey is ready to exit the pouch or has died, whereupon the embryo proceeds to develop and is born at a time when the pouch is available. This unusual type of reproduction, which is found in many kangaroos, enables the female to quickly replace young that have died due to drought or predators, and have an embryo ready to develop when conditions become favorable.

Common wallaroos make a sound like a hiss which is exhaled through the nose, as an alarm to nearby wallaroos. Then they stamp on the ground with their foot and run away.

Wallaroos use their tails as a third leg, to support them while sitting.