Common Wombat Vombatus Ursinus Research Articles

One year on: rapid assessment of fauna and red fox diet after the 2019–20 mega-fires in the Blue Mountains, New South Wales

ABSTRACT Australia’s 2019–20 mega-fires burnt 79% of the Greater Blue Mountains World Heritage Area, prompting an urgent need for rapid on-ground post-fire assessments of flora and fauna to aid in post-fire recovery. This project aimed to determine spatial patterns in populations and assemblages of vertebrates, vertebrate temporal activity, and the diet of the invasive Red Fox Vulpes vulpes, across burnt and unburnt sites. Using remote camera traps we surveyed 12 unburnt and 10 burnt sites approximately 12 months after the fires. We detected 41 species (11 mammals, 28 birds and 2 reptiles), with different species composition, but similar vertebrate species richness across both unburnt and burnt sites. The relative abundance of the Eastern Grey Kangaroo Macropus giganteus, Common Wombat Vombatus ursinus and Australian Magpie Gymnorhina tibicen was higher in burnt sites, while small mammals (< 500 g) had higher relative abundance at unburnt sites. There was no difference in the relative abundance of the Superb Lyrebird Menura novaehollandiae across burnt and unburnt sites, and although 11 species of bird were only detected at unburnt sites, the numbers were too low for reliable estimates of differences. Red Fox scat analysis (n=23) revealed that invertebrates and plant material were the dominant prey items in both burnt and unburnt sites, but medium-sized mammals increased in Red Fox diets in burnt sites, and reptiles were consumed disproportionately more by Red Foxes in burnt compared to unburnt sites. Although the short-term nature of this study and low scat sample size limited detailed insights, our rapid survey was an effective tool to gain preliminary data on species responses to the 2019–20 megafires in the Blue Mountains and contribute to a baseline for understanding species recovery.

Conservation status of common wombats in Tasmania II: population distribution and trends, and the incidence and significance of roadkill

Understanding species’ distribution, population trends, and the significance of threatening processes are central to the effective conservation and management of wildlife. The island state of Tasmania, Australia, is home to two of the three extant subspecies of common wombat Vombatus ursinus ursinus and V. u. tasmaniensis, both endemic to the state. We provide a comprehensive conservation assessment of both subspecies in Tasmania, providing information on distribution and habitat, population trends and incidence of roadkill. Wombats are widespread in Tasmania, occurring in most vegetation communities, but particularly in agricultural areas, dry eucalypt forests and woodlands, and grasslands. Wombat roadkills are widespread along most major roads, with the interaction of traffic speed and wombat density likely to be one of the main causes of wombat roadkill along roads with low traffic volume. Despite this, and other factors that impact wombats including sarcoptic mange and targeted culling, population indices from standardised spotlight surveys have increased by 2.6 times over the past 36 years for V. u. tasmaniensis on mainland Tasmania and by 4.2 times over the past 27 years for V. u. ursinus on Flinders Island. Based on IUCN criteria for distribution extent and population size and trends, neither subspecies qualifies for up-listing to Threatened. Nevertheless, because of risks to wombats (e.g. disease and roadkill) ongoing monitoring and research into effective mitigation is warranted.

Bennett’s wallaby ( Macropus rufogriseus) marrow quality vs quantity: evaluating human decision-making and seasonal occupation in late Pleistocene Tasmania

A pilot study on the fatty acid composition of the bone marrow, brain tissue and muscle (flesh) of the medium-sized marsupial the Bennett’s wallaby ( Macropus rufogriseus), aimed to explore the mechanisms behind the dominance of this human prey species in late Pleistocene southwest Tasmania. In particular it was designed to investigate why humans frequently selected and transported the wallaby hindquarters, breaking open their longbones and metatarsals to expose the marrow cavity, when these animals could easily have been transported whole. Initial results indicated that the percentage of unsaturated fatty acids particularly palmitoleic acid (C 16:1) and oleic acid (C 18:1) in the bone marrow increased distally away from the body core temperature or the heart, towards the hands and feet. There is a corresponding decrease in the percentage of the saturated fatty acids, particularly palmitic acid (C 16:0) and stearic acid (C 18:0). This is similar to the pattern identified in placental artiodactyls (even-toed ungulates) and rodents. The preliminary study was then expanded to a year-long seasonal experiment involving wallabies from different Tasmanian environmental and climatic zones to see if this can better help explain the apparent seasonal occupation of caves indicated from recent Bennett’s wallaby teeth annuli (Skeletochronological studies). It was found that the Bennett’s wallaby remained a relatively stable and dependable resource throughout the year, with environmental, altitudinal and seasonal variability having only a minor effect on the fatty acid composition or nutritional quality of their bone marrow, muscle and brain tissue. Interestingly, the animals had increased desirable unsaturated fatty acids in their marrow, muscle and brain during the winter and spring with decreased amounts during the summer and autumn. This lends support to an earlier Kidney Fat Index (KFI) analysis for the Bennett’s wallaby which recorded significant seasonal differences within and between regions, indicating an environmental effect on overall body condition. Fatty acid analysis of the Common wombat Vombatus ursinus, the Tasmanian pademelon Thylogale billardierii, and the Forester or Eastern Grey kangaroo Macropus giganteus were also included to ascertain why these animals remained constant, although minor, prey species throughout the late Pleistocene. While the results from these animals were similar to the Bennett’s wallaby, there were some unexpected and surprising patterns that require further investigation. All of these fatty acid analyses have important implications for understanding human decision-making and occupation of southwest Tasmania during the Last Glacial Maximum, for modern dietary and palaeodietary benefits, and for understanding the physiology of these unique Australian marsupials.

The governor's wombat: early history of an Australian marsupial

This paper gives an account of the European discovery of an Australian marsupial, the common wombat Vombatus ursinus, with particular reference to the first complete wombat specimen to reach Europe, which survives in The Hancock Museum, Newcastle upon Tyne. The involvement of colonial officials, navigators, explorers, naturalists and artists is discussed.

Field observation of daytime courtship and mating of the common wombat Vombatus ursinus.

A pair of wombats (Vombatus ursinus) near Braidwood NSW, were observed in the early afternoon for over one hour during which time the darker and greyer animal (male) followed close (about 2 m) behind the larger, tawny furred animal (female). They followed a fixed path over a 0.25 ha area of short grass. Copulation occured 4 times with the male partly on its side at right angles acroos the hind quarters of the female.

Sarcoptes scabiei: an important exotic pathogen of wombats

Sarcoptes scabiei is a parasitic astigmatid mite, which causes scabies in people and sarcoptic mange in mammals. Importantly, it is an emerging disease in wildlife throughout the world. The mite originates from a human ancestor and is thought to have spread to domestic and then free-living animals. Based on the recent emergence of sarcoptic mange in Australian wildlife and Aboriginal communities, it is thought that Sarcoptes scabiei was probably introduced to Australia by the Europeans and their animals. The mitochondrial genetic similarity of mites from Australian wildlife and domestic animals supports this. In Australian wildlife, sarcoptic mange has been reported in the common wombat Vombatus ursinus, southern hairy-nosed wombat Lasiorhinus latifrons, koala Phascolarctos cinereus, common ringtail possum Pseudocheirus peregrinus and in 2003 in the agile wallaby Macropus agilis. Compared with other native species, sarcoptic mange has by far its greatest impact on wombats, particularly common wombats, and is capable of causing high morbidity and mortality rates.

Female dispersal and relatedness structure in common wombats (Vombatus ursinus)

AbstractDispersal patterns were investigated in the common wombat Vombatus ursinus using microsatellite genetic data collected from three study sites. Two of these were within large, high‐density populations in Victoria, south‐eastern Australia, while the third was a small, isolated population in South Australia. Genetic assignment tests revealed that in the continuous populations, females were more likely to be immigrants into the sampling areas than were males, who were more likely to have been born locally. No such difference between the sexes was detected for the isolated population. At all three sites, pairwise relatedness estimates for males were negatively correlated with geographic distance, suggesting related males were clustered. This pattern was not observed among females, other than in the isolated population, where pairs of females showed a weak decline of relatedness with increasing geographic distance over a large spatial scale. Taken together, these data provide strong evidence that dispersal is predominantly by females. Furthermore, the observed spatial structure of relatedness suggests female breeding dispersal, a rare finding among mammalian species. Genetic variation within the isolated population was significantly reduced compared to the sites in Victoria. Our data are not sufficient to distinguish between two possible causes for this: (1) long‐term small size and isolation of populations at the edge of the species' range where resources may be more patchily distributed; (2) a genetic bottleneck effect of recent isolation resulting from agricultural development.

Observations on the behaviour and ecology of the Common Wombat Vombatus ursinus in northeast Tasmania.

Aspects of the behaviour and ecology of Vombatus ursinus were studied in largely cleared agricultural land in a coastal area in northeast Tasmania. The average density of V. ursinus was 20 individuals.km-2 over the whole study area but around 60.km-2 in an intensively studied section. Burrows were concentrated in areas of sandy soil where a dense cover of native vegetation had been maintained. Only short, shallow burrows were present in areas of dolerite, probably because of the difficulty of digging. Home-ranges of different individuals overlapped. Wombats were not active continually through the night and varied in time of emergence from their burrow and the time spent above ground. Often more than one burrow was used on the same night, with more than one individual making use of a burrow, but usually not at the same time. Disputes over the use of burrows occurred. Individuals frequently sniffed around burrows and investigated for the presence of occupants. Males may use this as a strategy for finding females in oestrus. Mating behaviour was observed once. Wombats are solitary and actively avoid the presence of others. Odour in faecal pellets and from scent marking probably plays an important social role by providing information on the individuals sharing a home-range and the occurrence of strangers. Dominant animals may be intolerant of the presence of certain individuals within their home-range.

Osteological Differences of the Skulls of Lasiorhinus-Latifrons Owen, 1845 and Vombatus-Ursinus Shaw, 1800 (Marsupialia, Vombatidae)

The two extant genera of wombats, the hairy-nosed wombat Lasiorhinus latifrons and common wombat Vombatus ursinus, are distinguishable by their skull morphology. Significant size differences were found for skull length, nasal length binasal breadth, bitemporal breadth, bizygomatic breadth, parietal bone thickness and mandible length. The important different gross morphological features are summarised to allow rapid identification of these two species. A number of new diagnostic differences are described which distinguish the species from dorsal, lateral and ventral views and on the basis of mandibles and dentition. Some of these differences, and those listed in the results, also distinguish the Pleistocene fossil wombats V. mitchelli (Owen, 1838) and L. krefftii (Owen, 1871) from each other, and strongly suggest their generic status.