Lasiorhinus latifrons (Owen, 1845)

Russell A. Mittermeier & Don E. Wilson, 2015, Vombatidae, Handbook of the Mammals of the World – Volume 5 Monotremes and Marsupials, Barcelona: Lynx Edicions, pp. 418-434 : 433-434

2.

Southern Hairy-nosed Wombat

Lasiorhinus latifrons

French: Wombat du Sud / German: Sidlicher Haarnasenwombat / Spanish: Uémbat de hocico peludo meridional

Other common names: Broad-fronted Wombat, Long-eared Wombat, Plains Wombat, Soft-furred Wombat

Taxonomy. Phascolomys latifrons Owen, 1845 ,

“Continental (South) Australia.”

Described by R. Owen from a single skull from South Australia forwarded to him by Govenor Gray. First living specimens of L. latifrons recorded from the Gawler region, north of Adelaide, Australia. Monotypic.

Distribution. S Australia, restricted to four major populations and a number of smaller colonies in semi-arid regions of SE Western Australia (W Nullarbor Plain) and S South Australia (E to Murray River). Introduced into Wedge I, South Australia.

Descriptive notes. Head-body 84-111 cm, tail 2.5-6 cm; weight 17.5-36 kg. The Southern Hairy-nosed Wombat is not significantly sexually dimorphic, but it is smaller than the Common Wombat ( Vombatus ursinus ). The Southern Hairy-nosed Wombatis a stocky and robust, with broad flat head, short neck, and powerful limbs. It is distinguished by a soft, velvety, furred rhinarium surrounded by an array of vibrissae (“hairy-nosed”), pointy ears, and soft silky fur. Continuously erupting lower incisors are rectangular in cross section. Valley that bisects dilambodont cheek teeth is acutely V-shaped,as distinct from the U-shaped valley in the Common Wombat. Southern Hairy-nosed Wombats are plantigrade; digits on manus and pes face forward. Narrow unguals are scoop-like, relatively long, and curve ventrally. Digits two and three of the pes are syndactylous (fused).

Habitat. Open plains, semi-arid grasslands, chenopod shrublands, and savanna woodlands. The Southern Hairy-nosed Wombat once formed an almost continuous population stretching from west of the Murray River in South Australia to the Western Australian side of the Nullarbor Plain. Today, this population is fragmented and confined to four main areas: Nullarbor Plain, Eyre Peninsula, Gawler Ranges, and Murray lands. Small remnant populations occur on Yorke Peninsula; they occupy areas subject to high drought frequency. Survival ofjuvenile Southern Hairy-nosed Wombats depends on good plant growth at the time of weaning in spring. This requires effective rainfall in late autumn to promote germination and growth of native grasses. Number of years of effective autumnal rainfall over much of their current distribution is 10-20%. These data suggest that, on average, only one in every five years are likely to result in major periods of recruitment to the population.

Food and Feeding. Southern Hairy-nosed Wombats mainly eat native tuft grasses ( Poaceae ); spear grasses ( Austrostipa spp.), kangaroo grasses ( Themeda spp.), and wallaby grasses ( Danthonia spp.) are preferred dietary genera. These grasses are considered annuals; however,if spared heavy grazing and allowed to establish a good root system in “wet” years, they will perenniate (live for multiple years). As perennial tufts, they continue to produce whorls of small green shoots that are sought by Southern Hairy-nosed Wombats. Their divided upper lip allows them to pluck shoots close to the ground. They will also graze various native sedges and forbs, but these are minor parts of their diets. In heavily degraded pastures, Southern Hairy-nosed Wombats will dig up corms of the introduced thread iris ( Moraea setifolia , Iridaceae ). Many areas of native pastures have been heavily invaded by exotic and unpalatable Ward’s weed ( Carrichtera annua , Brassicaceae ). Relatively recent appearances in degraded pastures of large infestations of more toxic introduced weedy species, such as the South African onion grass ( Romulea rosea , Iridaceae ), have been linked to a variety of health problems in Southern Hairy-nosed Wombats, including skin lesions, blindness, and liver dysfunction.

Breeding. Southern hairy-nosed Wombats are seasonal and opportunistic breeders. Birth of young occurs in July-December, peaking in October. Reproductive activity may vary from year to year, declining significantly in years following low rainfall. It is likely that effect of rainfall on pasture quality and quantity has a direct influence on ovulation and sperm production in Southern Hairy-nosed Wombats. Estrus lasts up to 36 days. Females are monogamous. Following insemination, male prostate fluids form a copulatory plug. Gestation is c.21 days. A single young is born, which makes its way unaided to the pouch where it attaches to one of two teats. Pouch life is c.7 months, weaning occurs at c.12 months. Juvenile Southern Hairy-nosed Wombats remain with their mothers until sexual maturity at 2-3 years, depending on growth rate. Young adult females tend to remain in their home warren longer than young males. As a population expands, older adult females disperse and leave their warrens to their offspring.

Activity patterns. Southern Hairy-nosed Wombats spend c.75% of their time below ground. Aboveground activity is influenced by need to conserve water and energy. In summer, Southern Hairy-nosed Wombats emerge during cooler parts of the evening, and in winter, their grazing activity shifts toward late afternoon and early evening. On still warm days following cold evenings, adults may bask around midday on the spoil mound at the burrow entrance. Young may often be observed at these times gamboling about the mound. Southern Hairy-nosed Wombats will drink from puddles left after rare summer thunderstorms. Cleaning out burrows, including desiccated carcasses of those that did not survive through summer, marks onset of the mating season.

Movements, Home range and Social organization. Home ranges of Southern Hairynosed Wombats are quite small at 1-3-4-8 ha and centered on home warrens. These warrens vary in areal extent, with some covering up to several thousand square meters, and may contain as many as 50 or more burrow entrances. These large warrens can be quite old and in continuous use for generations. Ten or more Southern Hairy-nosed Wombats may share a large warren but rarely share burrows; adults are essentially solitary. Home ranges are similar between sexes and may overlap. A network oftrails connects warren systems. Trails include rubbing posts and wallows, are visited regularly, and are marked by feces and urine. Eyesight of Southern Hairy-nosed Wombats is poor, but olfactory and auditory senses appear quite acute.

Status and Conservation. Classified as Least Concern on The IUCNRed List. Once widely distributed across South Australia from west of the Murray River to the eastern border regions of Western Australia, overall population of Southern Hairy-nosed Wombats is now fragmented. Largest groupings occur on the Nullarbor Plain (50,000-100,000 individuals) and in the Murray lands (10,000-15,000 individuals). Smaller scattered populations occur in the Gawler Ranges, around Elliston, Lake Everard, and on Yorke Peninsula. Larger populations occupy regions of high drought frequency, many on the margins of arid and semi-arid lands. Recruitment of young Southern Hairy-nosed Wombats is sporadic, requiring 2-3 years of effective rainfall to promote and sustain growth of the native grasses on which they depend. Overgrazing by European Rabbits (Oryctolagus cuniculus), sheep, and kangaroos has degraded many of native grasslands. Restoration of habitat is a key priority for long-term conservation of the Southern Hairy-nosed Wombat.

Bibliography. Aitken (1971b, 1973), Alpers et al. (1998), Angas (1861), Beheregaray et al. (2000), Brooks et al. (1978), Brown (2011), Byard et al. (1998), Copley (1995), Crowcroft (1967), Descovich et al. (2012), Dierenfeld (1984), Finlayson (2002), Finlayson, Shimmin et al. (2005), Finlayson, Taggart et al. (2007), Flosser (1984), Forward (1985), Frappell et al. (2002), Gaughwin (1979, 1981, 1982), Gaughwin & Judson (1980), Gaughwin, Breed & Wells (1998), Gaughwin, Judson et al. (1984), Hamilton et al. (2000), Hogan, Johnston et al. (2011), Hogan, Phillips et al. (2010), Jenkins (1962), Krefft (1872), Lehman (1979), Macalister (1872), McGregor (1992), McGregor & Wells (1998), Owen (1845, 1872), Ruykys et al. (2009), Sanderson & Nelson (1998), Sanderson & Pearson (1981), Shimmin et al. (2002), St. John (1998), St. John & Saunders (1989), Steele & Temple-Smith (1998), Stott (1998), Taggart & Robinson (2008), Taggart & Temple-Smith (2008), Taggart, Finlayson et al. (2007), Taggart, Shimmin et al. (2005), Taggart, Steele et al. (1998), Tartowski & Stelmann (1998), Taylor (1998), Tiver (1980, 1981), Treby (2005), Trumble (1948), Walker, Sunnucks & Taylor (2006, 2008), Walker, Taylor & Sunnucks (2008), Wells (1968, 1973, 1978a, 1978b, 1989, 1994, 1995), Wells & Green (1998), Woolnough et al. (1997), Wood Jones (1925).

Figures

1. Common Wombat (Vombatus ursinus), 2. Southern Hairy-nosed Wombat (Lasiorhinus latifrons), 3. Northern Hairy-nosed Wombat (Lasiorhinus krefftii)

Distribution. S Australia, restricted to four major populations and a number of smaller colonies in semi-arid regions of SE Western Australia (W Nullarbor Plain) and S South Australia (E to Murray River). Introduced into Wedge I, South Australia.