Northern Hairy-nosed Wombat

SPECIES Northern Hairy-nosed Wombat
TAXONOMY Lasiorhinus krefftii
STATUS Critically endangered (Redlist.org); Critically endangered (ala.org.au)

The Northern Hairy-nosed Wombat is one of three species of wombats native to Australia. Of the three; the Northern Hairy-nosed is found in the arid inland regions of Queensland, the Southern Hairy-nosed is found in semi-arid southern regions of Australia, whilst the Common Wombat occupies the eastern coastal and high country to the south. The Northern Hairy-nosed was once more widespread but now can only be found in two small regions residing within National Park refuge areas. The NHN Wombat has been recorded to live at least 26 years in this protected environment.

The wombat is not only a marsupial, it is the world’s largest burrowing herbivore. They feed on both native and introduced grasses. They have strong claws which are used to dig extensive networks of tunnels of up to 90 meters long, include several entrances, and can be up to 3.5 meters below ground often utilising tree roots for supporting framework. They will mark the entrance with dung, urine, and identifiable scratchings. They produce faeces in the distinctive shape of a cube which is thought to keep it from rolling away.  Although they are considered solitary and the tunnels are only wide enough for a single wombat to pass, it has been found that the burrows are sometimes shared with other adults.

The wombat is nocturnal, using the burrow for protection against extreme heat and cold. In winter, they have been seen sunning themselves. Spending much of their time deep within the climate protection of the burrow allows them to conserve water and energy in arid environments. 

Generally considered slow and lethargic, they can actually move up to 40 kph over a short distance. They will defend home territories through aggressive behaviour such as inflicting puncture wounds, deep bites, and charging towards predators. Alternatively, they will dive into their burrow head first and block the entrance with their sturdy, tailless rump.

Appearance
Of the three wombat species, the Northern Hairy-nosed is the largest. It can weigh up to 40 kgs and be up to 1 metre in length. It has long pointed ears, short nasal bones, and a square muzzle fringed with fine whiskers. It has soft, dark fur.

The Wombat is the closest living relative to the Koala and they share many traits. They both have vestigial tails which means that the tail is not external. They both have cheek pouches, few premolar teeth, and unique blood proteins. Wombats teeth continue to grow at the same rate as they are worn through use. This affords the possibility that the animal will continue to maximise the nutritional content of its diet throughout its lifespan.

Reproduction
NHN Wombats give birth in late spring or summer to a single joey.  The joey will stay in the protection of the pouch for up to nine months. As with other burrowing marsupials, the pouch faces backwards so when the mother digs, the pouch does not fill up with soil. Joeys vary in the amount of time it takes them to gain independence. The females reach sexual maturity at 2.5 years. Breeding rates occur between 50 to 80% of females when environmental conditions promote abundant feed.

Threats
The NHN Wombat is listed as Critically Endangered with less than 200 individuals remaining. At the time of European settlement, the NHN Wombat incurred a decline in population as the introduction of domestic grazing animals created competition for food sources. Since that time, a number of factors are continuing to contribute to their loss.

  • Competition for food with native species (Eastern Grey Kangaroo within the National Park)

  • Habitat loss through clearing and change of use

  • Predation by wild dogs

  • Extended droughts

  • Major flooding events

  • Changing wildfire patterns remove food sources

  • Loss of genetic diversity due to small population

  • Disease opportunities

There is a current and serious threat impacting other species of wombats throughout Australia. It is Sarcoptic Mange and is caused by the burrowing parasitic mite, Sarcoptes scabiei. This affects more than 100 mammalian species worldwide including humans and dogs. The parasite is referred to as scabies in humans and mange in other species. Along with the Southern Hairy-nosed Wombat and the Common Wombat, other species include ringtail possums, bandicoots, and koalas. It is prevalent in wombats due to the burrow environment that they live in.

The female mite burrows under the skin where it deposits eggs. These hatch and cause intense discomfort due to the consumption of skin and constant irritation. The animal aggressively scratches, causing hair loss, skin thickening and crusting, skin discolouration, open wounds, weight loss, and sleep deprivation. Secondary infections occur through fly strike. It can also cause blindness, deafness, organ failure, and eventual death. It is possible to treat this condition in captivity, but nearly impossible in wild populations. The Northern Hairy-nosed Wombat has not yet been affected simply due to its isolation. 

Updated 5 May 2021