Lasiorhinus krefftiinorthern hairy-nosed wombat
Geographic Range
Lasiorhinus krefftii used to be abundant in New South Wales until the settlement of Europeans in the area after 1872. There were populations near St. George in South Queensland and near Jeriderie in New South Wales until around 1910. The sole population of the hairy-nosed wombat is now in the Epping Forest National Park, northwest of Clermont in Central Queensland.
- Biogeographic Regions
- australian
Habitat
Hairy-nosed wombats are terrestrial and build burrows. They spend time both above and below ground. They live in semi-arid, open woodlands or grasslands.
- Terrestrial Biomes
- savanna or grassland
Physical Description
These wombats are heavily built with very powerful forearms. They have a thick, stocky body that averages one meter (3.25 ft) in length. Their heads are large, with small eyes and pointed ears. Currently they are one of the world's largest burrowing animals. Males and females are both covered with a soft, silky brown coat. They have long whiskers extending from the sides of their noses -- hence the name hairy-nosed wombat. The females have posteriorly-oriented pouches. They also have continuously growing upper molars due to their diet.
- Other Physical Features
- endothermic
- bilateral symmetry
-
- Range mass
- 25 to 40 kg
- 55.07 to 88.11 lb
Reproduction
There is a single mating season per year that takes place in the spring/summer period. Time of birth ranges from November to March. Hairy-nosed wombats give birth to a single young. It has recently been hypothesized that heavy rainfall in the winter months prior to the mating season is positively correlated with birth rate. This is most likely because rain makes the native grasses more abundant. Observations on their natural habitat have revealed low subadult survivorship, but without revealing why this occurs. The young wombat is carried in the mother's pouch for approximately six months, and it is nursed for eight to nine months. Unfortunately, almost nothing is known about the details of their reproduction or gestation because it is very difficult to observe them in the wild, and in captivity they do not fare well. Trapped animals are kept only for a short period of time.
- Key Reproductive Features
- gonochoric/gonochoristic/dioecious (sexes separate)
- sexual
-
- Average number of offspring
- 1
- AnAge
Lifespan/Longevity
-
- Average lifespan
Status: captivity - 30 years
- AnAge
- Average lifespan
Behavior
The hairy-nosed wombat is very solitary, thus hard to observe in the wild. What is known, however, is that they construct very large and intricate tunnel systems (called warrens) in deep sand. They use the roots of trees as a "roof" for their larger tunnels. Their burrow system was estimated to be enclosed in a 300 ha area. Most of their burrows have multiple entrances that lead to single burrow complex. Individual wombats rarely use the same burrow simultaneously, but they do use burrows of previous generations. Occasionally males and females are found together. Hairy-nosed wombats are monogamous. They have a home range of approximately 15 acres. Although they are nocturnal feeders, they like to sunbathe close to their tunnel entrances early in the day. In G. Gordon's experiments (1985), it was found that there was a postive correlation between numbers of wombats and kangaroos in areas of grassland, but a negative correllation between numbers of wombat and cattle.
- Key Behaviors
- motile
Communication and Perception
Food Habits
The hairy-nosed wombat is strictly herbivorous and feeds on the native grasses in the park where it resides. These grasses include Hetropogon contortus (bunch spear grass) and Aristida spp. (three-awned grass). The wombat's decline in numbers has mostly been due to competition from local cattle for the grass they both feed upon. These animals have weak eyesight combined with a good senses of smell and hearing, and their activity is nocturnal.
Economic Importance for Humans: Positive
Until recently, the northern hairy-nosed wombat was widely hunted for its fur, which has high commercial value.
Economic Importance for Humans: Negative
The rigorous conservation attempts for this wombat have been costly to the Australian government and other independent sources. They have also been a problem for cattle raisers because they have been forced to find new areas for their cattle to graze. This is especially difficult because this area of Australia is plagued by droughts (a problem for the wombats themselves.)
Conservation Status
Lasiorhinus krefftii are extremely endangered and there have been massive efforts to prevent their extinction. Although previously avoided at almost all costs, trapping has now become a major tool for conservationists to build up this population of wombats. The trapping experiments were begun in 1985. In 1981 it was estimated that there were only 20-40 wombats left, but now the estimated number of wombats is around 70. The local cattle in the area have been the largest problem for the population in recent years. There are now strict restrictions on cattle grazing in the park. The wombats used to be abundant before European settlement as well.
-
- IUCN Red List
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Critically Endangered
More information
Other Comments
One very interesting fact about this species is their loss of heterozygosity. Measurements of DNA variability made on DNA extracted from specimens from extinct populations of this wombat (Deniliquin, New South Wales) revealed that Epping Forest populations have only 41% of the variability of the extinct population, suggesting a bottlenecked species in steady decline.
Contributors
Megan Schober (author), University of Michigan-Ann Arbor.
Glossary
- Australian
-
Living in Australia, New Zealand, Tasmania, New Guinea and associated islands.
- bilateral symmetry
-
having body symmetry such that the animal can be divided in one plane into two mirror-image halves. Animals with bilateral symmetry have dorsal and ventral sides, as well as anterior and posterior ends. Synapomorphy of the Bilateria.
- chemical
-
uses smells or other chemicals to communicate
- endothermic
-
animals that use metabolically generated heat to regulate body temperature independently of ambient temperature. Endothermy is a synapomorphy of the Mammalia, although it may have arisen in a (now extinct) synapsid ancestor; the fossil record does not distinguish these possibilities. Convergent in birds.
- motile
-
having the capacity to move from one place to another.
- native range
-
the area in which the animal is naturally found, the region in which it is endemic.
- sexual
-
reproduction that includes combining the genetic contribution of two individuals, a male and a female
- tactile
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uses touch to communicate
- tropical savanna and grassland
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A terrestrial biome. Savannas are grasslands with scattered individual trees that do not form a closed canopy. Extensive savannas are found in parts of subtropical and tropical Africa and South America, and in Australia.
- savanna
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A grassland with scattered trees or scattered clumps of trees, a type of community intermediate between grassland and forest. See also Tropical savanna and grassland biome.
- temperate grassland
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A terrestrial biome found in temperate latitudes (>23.5° N or S latitude). Vegetation is made up mostly of grasses, the height and species diversity of which depend largely on the amount of moisture available. Fire and grazing are important in the long-term maintenance of grasslands.
References
Emanoil, M. (editor). Encyclopedia of Endangered Species. Gale Research, Inc. Detroit. 1994
Gordon, G.; Riney, T.; Toop, J.; Lawrie,B.C.; Goodwin, M.D. 1985. Biological Conservation. 33(2): 165-195
Boorer, M. Mammals of the World. Grosset &Dunlap, New York. 1971
Hoyle, S.D. 1995. Wildlife Research 22(6): 741-755
Morris, D. The Mammals, Harper & Row. New York. 1965
Roy. 1994. Experentia (Basel) 50(6): 551-557
Taylor, A.C. 1994. Molecular Ecology 3(4): 277-290