Nailtail wallabies have fared very badly since European occupation. One is now extinct, one rare and only one remains common locally.
The Northern Nailtail Wallaby (Onychogalea unguifera), also known by the common names of Organ-grinder, Karrabul and Sandy Nailtail, is a small sandy wallaby which can be identified by a dark stripe on the lower mid-dorsal continuing onto the tail, a tuft of dark hairs towards the end of the tail and a nail on the tip of the tail. Males, grow to a maximum head and bodylength of just under .7 of a metre with a tail that often exceeds .7 of a metre. They usually attain a weight of around 7 to 8 kilograms. Females are usually around 10 percent smaller in size and weigh around 5 to 6 kilograms.
Little is known of its biology but its preferred habitats in the Northern Territory appear to be lightly wooded flood plains in the north and open long-grass woodland and shrub-savannah in the south. It is occasionally found on rocky slopes, as in the Tanami Range, NT, and is reputed to have been common among paperbark scrub on the edges of open plains near Broome, WA. In northern Queensland its habitats range from open woodland with a grassy understorey to grassland with occasional trees. It appears to be more common near watercourses.
The Northern Nailtail Wallaby is solitary, but may form feeding aggregations of up to four animals. It is active between dusk and dawn. The species, with a status regarded as common in its range, has survived European settlement much better than the other nailtail wallabies. Although its distribution is patchy and it may have suffered some local extinctions, it appears to be in no danger.
The Bridled Nailtail Wallaby (Onychogalea fraenata), also known by the common names of Flashjack, Pademelon, Merrin and Waistcoat Wallaby, has a white 'bridle' line running from the centre of the neck down behind the forearms on either side of the body and a horny pointed 'nail' on the tail tip. Males, grow to a maximum head and bodylength of just over .5 of a metre with a tail that reaches a further .5 of a metre. They usually attain a weight of 5 to 6 kilograms. Females are usually around 20-25 percent smaller in size and weigh around 4 to 5 kilograms.
With a status regarded as rare in its limited range, the Bridled Nailtail Wallaby is one of a number of mammals whose populations declined spectacularly after European settlement. Reports by the naturalists Gilbert, Gould, Lumholtz and Krefft showed that in the mid-nineteeth century it ranged from the Murray River to charters Towers, Qld, and was common over at least part of the range. Even around the turn of the century it was present in sufficient numbers to be shot for its pelts but today it is known only as a small population near Dingo in central Queensland. It was an animal of the semi-arid inland, living mostly on the slopes and plains to the west of the Great Dividing Range in a mixture of shrubland and grassy woodland.
The surviving population live in a district with more fertile soils which support open eucalypt forest, woodland and brigalow scrub. This population has a habitat preference for the scrub edges, grazing and sheltering in the shrubland and grazing in the grassy woodland.
During the day, the Bridled Nailtail Wallaby rests in a slightly dished patch of bare ground scratched out beside a bush or tree. Around dusk it commences to feed. In central Queensland it is seen in greater numbers as the dry season progresses, indicating that it ventures further from the scrubs as the pasture deteriorates. It is usually solitary but females may have young at heel and aggregations of four or five animals are not uncommon.
The escape behaviour is interesting. Some seek refuge in hollow logs when chased and one was observed by Gould to climb within the trunk of a hollow tree. A Bridled Nailtail Wallaby may avoid detection by lying prone in long grass in the same way as the spectacled Hare-wallaby, or by crawling out of sight under low shrubs where it remains even when closely approached. These reactions are all appropriate to a life in grassy woodlands, suggesting that the species has had a long association with this environment.
The Bridled Nailtail Wallaby has vanished from regions which have neither been extensively cleared for timber nor seriously affected by introduced predators. Its decline seems to be an effect of the pastoral industry, either through competition with stock for food or through destruction of ground cover. It is locally common now on an area of only 11,000 ha, part of which has been acquired as a fauna refuge for its protection.
The Crescent Nailtail Wallaby (Onychogalea lunata), known also as the Lunated Nailtail Wallaby, Wurrung (south-eastem Westem Australia) and Tjawalpa (western desert) is now presumed extinct. It was marginally smaller than the Bridled Nailtail Wallaby, mainly attributable to a shorter tail. The animal was generally ash grey in colour above and pale grey below, with a defined crescent like white shoulder stripe from the chest to the scapular regions. It also possessed an ill-defined, pale hip stripe and a homy nail at the tip of the tail.
John Gilbert, who collected the specimens upon which John Gould erected this species in 1841, noted that it
'is found in the gum forests of the interior of Western Australia, where there are patches of thick scrub and dense thickets, in the open glades intervening between which it is occasionally seen sunning itself, but at the slightest alarm immediately betakes itself to the shelter of the thick scrub...' (Gilbert's 'forests' would today be termed woodlands.)He stated it made no nest but formed a hollow in soft ground beneath a shrub. Early naturalists recorded that the Crescent Nailtail Wallaby, or Wurrung, would sometimes run into a hollow log when chased. B. W. Leake, an early settler of the Kellerberrin district, WA, noted that it would
'make for a hollow tree with a hole in the bottom. Into this it would go, and clamber up the sides, until it got some distance up inside the tree. To procure Wurrungs for food the Aborigines used to light a fire and smoke them out.'Leake said it lived in open timbered country. It was apparently quite plentiful in the agricultural districts of the southwest of Western Australia until just after the turn of the century. G. C. Shortridge collected 23 specimens for the British Museum from near Pingelly and Wagin between 1904 and 1907 but thereafter it declined rapidly, the last recorded specimen coming from Cranbrook in 1908. Leake noted its disappearance from Kellerberrin by 1899.
The Crescent Nailtail Wallaby also occurred in central Australia. The Elder expedition collected it in the Everard Ranges in northwestern South Australia in 1891. Previously, in 1888, three South Australian specimens had been sent to the British Museum by Sir George Grey, and Wood Jones later noted that it had been reported 'from the Centre' in 1884. The Horn Expedition of 1894 obtained two specimens from Alice Springs, extending the known range northward. In the 1930s Finlayson found it still occurring near the Everard Ranges as well as near the Musgrave Ranges, SA, and the Cavenagh Range, WA. Writing in 1961 he stated that it was still extant in some areas and that one had been killed between the Tarlton and Jervois ranges, NT, as late as 1956.
Aborigines from the Warburton-Giles area of Western Australia recall that the Crescent Nailtail Wallaby inhabited Mulga country and areas near creeks with River Gums. Both they and Aborigines from Yuendumu, NT, state that they have not seen it for many years. The report in Ride's 'A Guide to the Native Mammals of Australia' of a 1964 specimen from near the Warburton Range, WA, cannot now be substantiated.
Source: 'Complete Book of Australian Mammals' - Australian Museum, 1983.
The Nailtailed Wallaby is featured on the following Australian coins: