Kangaroos are marsupials and belong to the Family Macropodidae (i.e. big feet) that is grouped with the Potoroidae (potoroos, bettongs, rat-kangaroos) and Hypsiprymnodontidae (musky rat-kangaroo) in the Super-Family, Macropodoidea. This comprises around 50 species in
Two of the four species of Hare-wallabies that were identified at European colonisation of Australia are extinct. The only species which retains a broad geographic range is the Spectacled Hare-wallaby which also has a small population is southern New Guinea. The genus was once common in the deserts and tropics and south-west of Western Australia. Pastoralism and the introduction of livestock grazing and concomitant changes in fire management and release of rabbits, foxes and cats have wrought a devastating impacts on the attractive small wallabies. A characteristic, emphasised in the Spectacled Hare-wallaby, is the rufous fur around the eye. The Hare-wallabies have long feet with long claws but the fore-limbs are very delicate and short.
Spectacled Hare-wallaby (Barrow Island)
Lagorchestes conspicillatus conspicillatus ('spectacled hare dancer')
Barrow Island, Western Australia
Barrow Island was isolated from mainland Western Australia about 8,000 years ago by rising sea levels. It now forms Western Australia's second largest island (234 square kilometres) and is 56 km off the north-western coast about 1300 km from Perth. The process of isolation carried with it an ark of animal species. Amongst these are mammals that are threatened or extinct on mainland Australia. Isolation on Barrow Island of the Spectacled Hare-wallaby has lead to sufficient genetic drift to be recognised as a sub-species and in this case the type specimen of the species. The island has three other macropod species - Boodie (burrowing bettong), Barrow Island Wallaroo, Black-footed Rock-wallaby - amongst its 15 species of mammals, as well as 110 species of birds, 54 species of reptiles and one species of frog. Green and Flatback turtles breed along its coastline.
In 1910, Barrow Island was declared a Class A Nature Reserve and was relatively pristine since it did not readily support pastoralism. Most exploitation was of marine resources such as turtles and peal oysters. However, in the 1950s oil was discovered but exploitation was delayed by the use of nearby Montebello Islands (about 16 km north) as an atomic testing site for the United Kingdom. This lead to the island's 'dubious' protection until the early 1960s when oil drilling commenced. By 1966 100 million barrels of oil had been produced and average production today is about 14,000 barrels with an expected lifetime through to 2020. Oil production has managed to be conducted with due environmental care over four decades without species loss. Even so impacts typical of human habitation and industry occur including roadkill, addition of water resources, nutrient outflows and the obvious excision of land for the oil industry. There is current concern about a large increment in industrial activity through the Gorgon Gas Project that will add a large-scale gas processing plant and associated equipment to the island.
Some general information about Barrow Island can be found at www.abc.net.au/nature/island/ep3/default.htm. Chevron Asiatic (www.chevron.com) operates the oil production and some counterviews about sustainability of the conservation values of the island can be found at www.rescuebarrowisland.org.au. The island is accessed from the port of Onslow, 88 km to the southeast.
Since access to Barrow Island is restricted, this destination is unrealistic for most tourists. The entry in 'The Mammals of Australia, 3rd Edition' by Burbidge and Johnson suggests the Spectacled Hare-wallaby remains common but patchily distributed in Queensland (the areas of tussock grasslands between Boulia and Mt Isa) and the Northern Territory (from the northern Tanami Desert to Arnhem Land but uncommon near the coast) but has much declined in Western Australia (Kimberley and Pilbara regions except Barrow Island). Thus the mainland subspecies is a better focus of a quest to see this species.
The Spectacled Hare-wallaby is found in tropical grasslands, especially tussock-forming species including spinifex, which may be overlain by a variety of vegetation (tall shrubland, open woodland, open forest in Queensland; Acacia shrublands and tropical savanna in the Northern Territory; spinifex grasslands in Western Australia). The tussocks provide protection and the hare-wallabies tunnel into these and may have several shelters in their home-range. The tussocks also provide thermoregulatory benefits under hot ambient temperatures. This refuge behaviour is coupled with exceptionally efficient physiological mechanisms to conserve water leading to one of the lowest water turnovers (5.3% of total body water per day) of mammals of its size. Its eco-physiology allows it to inhabit dry, hot climates and not drink free-water.
Breeding can occur throughout the year. Gestation is 29-31 d and oestrus follows shortly after birth with post-partum mating. Embryonic diapause occurs in this species. Births are clumped on Barrow Island around the late Dry season (September) and towards the end of the Wet season (March). Pouch life is about 150 d and sexual maturity is reached within a year.
The species is typically solitary but small aggregations of around three individuals have been observed feeding in the same area. Thus home ranges are likely not exclusive and only shelter sites defended. THis deserves further study.
Burbidge AA, Johnson PM (2008). Spectacled Hare-wallaby. In The Mammals of Australia 3rd Edition, (Van Dyck S, Strahan R eds.) pp. 314-316. (New Holland Reed, Chatswood).
Ingleby S, Westoby M (1992) Habitat requirements of the spectacled hare-wallaby (Lagorchestes conspicillatus) in the Northern Territory and Western Australia. Wildlife Research 19, 721-741.
Short J, Turner B (1991) Distribution and abundance of spectacled hare-wallabies and euros on Barrow Island, Western Australia. Wildlife Research 18, 421-429.