Wallaby

For other uses, see Wallaby (disambiguation).

A red-necked wallaby

A wallaby (/ˈwɒləbi/) is a small or middle-sized macropod native to Australia and New Guinea, with introduced populations in New Zealand, the United Kingdom and other countries. They belong to the same taxonomic family as kangaroos and sometimes the same genus, but kangaroos are specifically categorised into the four largest species of the family. The term "wallaby" is an informal designation generally used for any macropod that is smaller than a kangaroo or a wallaroo that has not been designated otherwise.

There are nine species (including one that is extinct) of brush wallabies (genus Macropus, subgenus Notamacropus). Their head and body length is 45 to 105 cm (18 to 41 in) and the tail is 33 to 75 cm (13 to 30 in) long. The 16 named species of rock-wallabies (genus Petrogale) live among rocks, usually near water; two species in this genus are endangered. The two living species of hare-wallabies (genus Lagorchestes; two other species in this genus are also extinct) are small animals that have the movements and some of the habits of hares. The three species (also including one that is extinct) of nail-tail wallabies (genus Onychogalea) have one notable feature: a horny spur at the tip of the tail; its function is unknown. Often called "pademelons", the seven species of scrub wallabies (genus Thylogale) of New Guinea, the Bismarck Archipelago, and Tasmania are small and stocky, with short hind limbs and pointed noses. The swamp wallaby (genus Wallabia) is the only species in its genus. Another wallaby that is the only species in its genus is the quokka or short-tailed scrub wallaby (genus Setonix); this species is now restricted to two offshore islands of Western Australia which are free of introduced predators. The seven species of forest wallabies (genera Dorcopsis (four species, with a fifth as yet undescribed) and Dorcopsulus (two species)) are all native to the island of New Guinea. One of the brush wallaby species, the dwarf wallaby (Macropus dorcopsulus), also native to New Guinea, is the smallest known wallaby and one of the smallest known macropods. Its length is about 46 cm (18 in) from the nose to the end of the tail, and it weighs about 1.6 kg (3.5 lb).

Wallabies are hunted for meat and fur.

Etymology and terminology

The name wallaby comes from Dharug walabi or waliba. Another early name for the wallaby, in use from at least 1802, was the brush-kangaroo.

Young wallabies are referred to as "joeys", like many other marsupials. Adult male wallabies are referred to as "bucks", "boomers", or "jacks". Adult female wallabies are referred to as "does", "flyers", or "jills". A group of wallabies is called a "mob", "court", or "troupe". Forest-dwelling wallabies are known as "pademelons" (genus Thylogale) and "dorcopsises" (genera Dorcopsis and Dorcopsulus).

General description

An agile wallaby family

Although members of most wallaby species are small, some can grow up to approximately two metres in length (from the head to the end of the tail). Their powerful hind legs are not only used for bounding at high speeds and jumping great heights, but also to administer vigorous kicks to fend off potential predators. The tammar wallaby (Macropus eugenii) has elastic storage in the ankle extensor tendons, without which the animal's metabolic rate might be 30–50% greater. It has also been found that the design of spring-like tendon energy savings and economical muscle force generation is key for the two distal muscle–tendon units of the tammar wallaby (Macropus-Eugenii). Wallabies also have a powerful tail that is used mostly for balance and support.

Diet

Wallabies are herbivores whose diet consists of a wide range of grasses, vegetables, leaves and other foliage. Due to recent urbanization, many wallabies now feed in rural and urban areas. Wallabies cover vast distances for food and water, which is often scarce in their environment. Mobs of wallabies often congregate around the same water hole during the dry season.

Threats

Wallabies face several threats. Dingoes, domestic and feral dogs, feral cats, and red foxes are among their predators. Humans also pose a significant threat to wallabies due to increased interaction (wallabies can defend themselves with hard kicks and biting). Many wallabies have been involved in vehicular accidents, as they often feed near roads and urban areas.

Classification

Wallabies are not a distinct genetic group. Nevertheless, they fall into several broad categories. Brush wallabies of the genus Macropus, like the agile wallaby (Macropus agilis) and the red-necked wallaby (Macropus rufogriseus), are most closely related to the kangaroos and wallaroos and, aside from their size, look very similar. These are the ones most frequently seen, particularly in the southern states.

A red-necked wallaby (Macropus rufogriseus) joey in a pouch

Rock-wallabies (genus Petrogale), rather like the goats of the Northern Hemisphere, specialise in rugged terrain and have modified feet adapted to grip rock with skin friction rather than dig into soil with large claws. There are at least 15 species and the relationship between several of them is poorly understood. Several species are endangered. Captive rock-wallaby breeding programs, like the one at Healesville Sanctuary, have had some success and a small number have recently been released into the wild.

The banded hare-wallaby (Lagostrophus fasciatus) is thought to be the last remaining member of the once numerous subfamily Sthenurinae, and although once common across southern Australia, it is now restricted to two islands off the Western Australian coast which are free of introduced predators. It is not as closely related to the other hare-wallabies (genus Lagorchestes) as the hare-wallabies are to the other wallabies.

New Guinea, which was until fairly recent geological times part of mainland Australia, has at least five species of wallabies.

Natural range and habitat

Wallabies are widely distributed across Australia, particularly in more remote, heavily timbered, or rugged areas, less so on the great semi-arid plains that are better suited to the larger, leaner, and more fleet-footed kangaroos. They also can be found on the island of New Guinea.

Introduced populations

Wallabies of several species have been introduced to other parts of the world, and there are a number of breeding introduced populations, including:

• Kawau Island in New Zealand is home to large numbers of tammar, Parma, swamp and brush-tailed rock-wallabies from introductions made around 1870. They are considered pests on the island, but a programme to re-introduce them to Australia has met with only limited success.
• The Lake Tarawera area of New Zealand has a large tammar wallaby population.
• The South Canterbury district of New Zealand has a large population of Bennett's wallabies.
• On the Isle of Man in the Ballaugh Curraghs area, there is a population of over 100 red-necked wallabies, descended from a pair that escaped from the nearby Curraghs Wildlife Park in 1970.
• Hawaii has a small non-native population of wallabies in the upper regions of Kalihi Valley on the island of Oahu arising from an escape of zoo specimens of brush-tailed rock-wallaby (Petrogale penicillata) in 1916.
• In the Peak District of England, a population was established around 1940by five escapees from a local zoo, and as of September 2017, sightings were still being made in the area. At its peak in 1975, the population numbered around 60 individuals.
• The island of Inchconnachan in Loch Lomond, Scotland, has a population of around 28 red-necked wallabies introduced by Lady Colquhoun in the 1920s. Eradication to protect the native capercaillie has been proposed.
• There is also a small population on Lambay Island off the east coast of Ireland.Initially introduced in the 1950s and 1960s, more were introduced in the 1980s after a sudden population explosion at the Dublin Zoo.
• Populations in the United Kingdom that, for some periods, bred successfully included one near Teignmouth, Devon, another in the Ashdown Forest, East Sussex and one on the islands of Bute and Lundy. It has recently been reported by walkers in the Lickey Hills Country Park area of Birmingham that a pair of wallabies have been released or are loose there (East Tunnock Rambling Club Meeting, December 2010).
• In France, in the southern part of the Forest of Rambouillet, about 50 km (30 mi) west of Paris, there is a wild group of around 30 Bennett's wallabies. This population has been present since the 1970s, when some individuals escaped from the zoological park of Émancé after a storm.

Species

A female wallaby with a joey in the Tasmanian summer rain

The swamp wallaby is the only living representative of the genus Wallabia. This individual exhibits the species' unusual preference for browsing; note the use of the forelimbs to grasp the plant.

Three wallabies (one grey with a joey in her pouch and one white) in captivity in England

The term "wallaby" is not well defined and can mean any macropod of moderate or small size. Therefore, the listing below is arbitrary and taken from the complete list of macropods.

Genus Macropus, subgenus Notamacropus

• Agile wallaby, Macropus agilis
• Black-striped wallaby, Macropus dorsalis
• Dwarf wallaby, Macropus dorcopsulus
• Parma wallaby, Macropus parma (rediscovered, thought to have been extinct for 100 years)
• Red-necked wallaby, Macropus rufigriseus
• Tammar wallaby, Macropus eugenii
• Toolache wallaby, Macropus greyii †(extinct)
• Western brush wallaby, Macropus irma
• Whiptail wallaby, Macropus parryi

Genus Petrogale

• Allied rock-wallaby, Petrogale assimilis
• Black-flanked rock-wallaby, Petrogale lateralis
• Brush-tailed rock-wallaby, Petrogale penicillata
• Cape York rock-wallaby, Petrogale coenensis
• Godman's rock-wallaby, Petrogale godmani
• Herbert's rock-wallaby, Petrogale herberti
• Mareeba rock-wallaby, Petrogale mareeba
• Monjon, Petrogale burbidgei
• Mount Claro rock-wallaby, Petrogale sharmani
• Nabarlek, Petrogale concinna
• Proserpine rock-wallaby, Petrogale persephone
• Purple-necked rock-wallaby, Petrogale purpureicollis
• Rothschild's rock-wallaby, Petrogale rothschildi
• Short-eared rock-wallaby, Petrogale brachyotis
• Unadorned rock-wallaby, Petrogale inornata
• Yellow-footed rock-wallaby, Petrogale xanthopus

Genus Lagostrophus

• Banded hare-wallaby, Lagostrophus fasciatus
• Eastern hare-wallaby, Lagorchestes leporides †(extinct)
• Lake Mackay hare-wallaby, Lagorchestes asomatus †(extinct)
• Rufous hare-wallaby, Lagorchestes hirsutus

Genus Dorcopsis

• Black dorcopsis, Dorcopsis atrata
• Brown dorcopsis, Dorcopsis muelleri
• Gray dorcopsis, Dorcopsis luctuosa
• White-striped dorcopsis, Dorcopsis hageni

Genus Onychogalea

• Bridled nail-tail wallaby, Onychogalea fraenata
• Crescent nail-tail wallaby, Onychogalea lunata †(extinct)
• Northern nail-tail wallaby, Onychogalea unguifera

Genus Thylogale

• Brown's pademelon, Thylogale browni
• Calaby's pademelon, Thylogale calabyi
• Dusky pademelon, Thylogale brunii
• Mountain pademelon, Thylogale lanatus
• Red-legged pademelon, Thylogale stigmatica
• Red-necked pademelon, Thylogale thetis
• Tasmanian pademelon, Thylogale billardierii

Genus Dorcopsulus

• Macleay's dorcopsis, Dorcopsulus macleayi
• Small dorcopsis, Dorcopsulus vanhuemi

Genus Wallabia

• Swamp wallaby or black wallaby, Wallabia bicolor

Genus Setonix

• Quokka or short-tailed scrub wallaby, Setonix brachyurus

External links

• Roophilia – photographs of kangaroos and wallabies
• View the macEug2 genome assembly in the UCSC Genome Browser
• View the wallaby genome in Ensembl