Geographic Range
Bettongia lesueur
was once one of the most widespread mammals inhabiting the Australian mainland. It
could be found in all suitable habitats throughout mainland Australia, yet by the
early 1960’s had become extinct on the mainland and could only be found on the Australian
islands of Bernier and Dorre in Shark Bay, and Boodie Island and Barrow Island near
the Pilbara coast. Burrowing bettongs used to live on Dirk Hartog Island, but have
gone extinct from there as well.
- Biogeographic Regions
- australian
Habitat
When burrowing bettongs were still thriving on the mainland, their habitat was diverse,
including open eucalypt woodland with grass and shrub under story to sand ridge desert.
On the islands where they currently exist, they are found in a variety of habitats
including areas consisting of shrubs, grasses and herbs. On Bernier and Barrow islands
they show no habitat preference. On Dorre Island they prefer coastal dunes and habitats
dominated by
Triodia
. Burrowing bettongs build extensive burrows in areas with stony soils throughout
their current distribution, but used to build burrows in sandy soils on the Australian
mainland.
- Habitat Regions
- temperate
- terrestrial
- Terrestrial Biomes
- desert or dune
- savanna or grassland
- forest
- scrub forest
Physical Description
Burrowing bettongs are small, stocky animals similar to kangaroos. They have weakly
prehensile tails that can be used for gathering nest materials. They are the only
member of the family
Potoroidae
to inhabit burrows year round. They are light yellow to grey above, have a grey underbelly,
short, rounded ears and thick, lightly haired tails, much like those of kangaroos.
Bettongia lesueur
has a body length ranging from 370 mm to 400 mm with a 300 mm mean tail length. Body
mass is 0.4 to 1.8 kg for males and 0.5 to 1.7 kg for females. Males tend to be larger
in mass and other body measurements than females. They move strictly using their hind
limbs and only use their fore limbs and tail for support when stationary.
Burrowing bettongs can be distinguished from other
bettongs
mainly by their behavior, but also by their coloration. They often have a light yellow
coloration on top while other species have a light grey coloration. Woylies (
Bettongia penicillata
), which are similar in appearance to
Bettongia lesueur
, do not inhabit burrows and are not gregarious. The same is true of northern bettongs
(
Bettongia tropica
). Food habits also differ between
Bettongia
species. The dental formula of
potoroids
is 3/1, 1-0/0 2/2, 4/4 = 32-34.
- Other Physical Features
- endothermic
- homoiothermic
- bilateral symmetry
- Sexual Dimorphism
- male larger
Reproduction
Mating in
B. lesueur
is polygynous, with males mating with several females and maintaining harems within
their warrens. Both sexes become sexually mature after about five months. Males are
aggressive toward one another in defense of females. Females tend to be non-aggressive,
but have been observed being aggressive towards females outside of their warrens.
- Mating System
- polygynous
Bettongs
exhibit embryonic diapause. Lactation causes implantation to be delayed. While one
young is still in the pouch, another will not be born until the pouch young has either
been weaned after 115 days or has been lost. This allows the mother to have three
young relying on her at one time: one weaned but still under care, one in her pouch,
and one still in development. Oestrous lasts approximately 23 days.
- Key Reproductive Features
- iteroparous
- year-round breeding
- gonochoric/gonochoristic/dioecious (sexes separate)
- sexual
- viviparous
- embryonic diapause
Males invest in their young only to the point of protecting their harems. Females
carry young in the pouch and care for them until they are weaned, after about 115
days. Joeys accompany their mother in foraging until their independence, near 180
days.
- Parental Investment
- altricial
-
pre-fertilization
- provisioning
-
protecting
- female
-
pre-hatching/birth
-
provisioning
- female
-
protecting
- female
-
provisioning
-
pre-weaning/fledging
-
provisioning
- female
-
protecting
- female
-
provisioning
-
pre-independence
-
provisioning
- female
-
protecting
- female
-
provisioning
Lifespan/Longevity
There is little information on the lifespan of
B. lesueur
, but it is known to usually live three years in the wild.
Behavior
Bettongia lesueur
is a highly social and nocturnal species. Burrowing bettongs are active exclusively
after sunset and return to their burrows before sunrise. Burrowing bettongs are the
only gregarious member of their family and lives year round in burrows. Burrows are
made in stony soils and nests are constructed in burrows with grasses. Grasses are
carried in with the aid of their long, muscular tails. These burrows can be simple
to complex, with some having as many as 91 or as few as two entrances. For every two
entrances to a warren there are estimated to be two individuals. Burrows are complex
underground and have many interconnected passages. Burrowing bettongs dig with the
aid of their forefeet.
Burrowing bettongs forage alone, rather than in feeding aggregations even though they
live together in their warrens. They commonly travel from 60 meters to 2 kilometers
in search of food, but have been known to travel farther when food is scarce
Males can be aggressive toward other males in protecting their harems, while females
are generally docile. Both sexes are very vocal, using a variety of grunts, hisses,
and squeaks to communicate.
Home Range
Home ranges extend anywhere from 60 meters to 2 kilometers surrounding denning sites.
Some individuals have been known to travel farther in search of food but such occurrences
are rare.
Communication and Perception
Burrowing bettongs locate food using their keen sense of smell. They are also a tactile
species, and often dig for food.
Bettongia lesueur
is a highly vocal species, yet the range of noises or what they mean in a social
or defensive context has not yet been determined. They often make grunts, squeaks,
and hisses to communicate.
Food Habits
Burrowing bettongs are generally herbivorous but have been known to eat termites and
marine animal carcasses. They concentrate on the green parts of plants, seeds, fruits,
nuts, tubers, bulbs, flowers, and fungi. This species is partial to figs when available.
They are able to find food using their sense of smell.
- Animal Foods
- carrion
- insects
- Plant Foods
- roots and tubers
- seeds, grains, and nuts
- fruit
- flowers
- Other Foods
- fungus
Predation
Predation on
Bettongia lesueur
is extensive and is thought to be the cause of the extinction of the species from
the mainland and one island population. Introduced foxes (
Vulpes vulpes
) were the primary mainland predator of burrowing bettongs. Feral cats are the primary
reason for extinction of
B. lesueur
on Dirk Hartog Island. There is little information on native predators of burrowing
bettongs.
Ecosystem Roles
Burrowing bettongs are thought to compete with both black rats (
Rattus rattus
) and European rabbits (
Oryctolagus cuniculus
), although recent studies cast doubt on the importance of rabbits in the decline
of
B. lesueur
. Burrows of
B. lesueur
may be used by western quolls (
Dasyurus geoffroii
), greater bilbies (
Macrotis lagotis
), and silver-tail brushtail possums (
Trichosurus vulpecula
).
Economic Importance for Humans: Positive
Burrowing bettongs may be an ecotourism draw because of their rarity.
- Positive Impacts
- ecotourism
Economic Importance for Humans: Negative
Burrowing bettong are often thought of as a pest species in areas where crops are
present. Humans have hunted them to reduce their impact on crops and are one of the
causes for population declines.
- Negative Impacts
- crop pest
Conservation Status
Due to extinction from the mainland of Australia
Bettongia leseur
has been listed under the IUCN Red List as Vulnerable. Numbers on Barrow island are
near 5,000. The species is listed in Appendix I of CITES. It is considered endangered
by the US Fish and Wildlife Srevice.
Reasons for the decline of burrowing bettongs have been attributed to predation by
introduced
foxes
and
feral cats
. Competition from
rabbits
and
black rats
is also one reason for population declines due to reduced food availability. Fire
regimes that reduced vegetation of lowland shrubs, which is the primary food source
of this species, along with human hunts to reduce crop predation have contributed
to the decline of populations.
Other Comments
Additional Links
Contributors
Tanya Dewey (editor), Animal Diversity Web.
Jeffery Mayfield (author), University of Alaska Fairbanks, Link E. Olson (editor, instructor), University of Alaska Fairbanks.
- Australian
-
Living in Australia, New Zealand, Tasmania, New Guinea and associated islands.
- native range
-
the area in which the animal is naturally found, the region in which it is endemic.
- temperate
-
that region of the Earth between 23.5 degrees North and 60 degrees North (between the Tropic of Cancer and the Arctic Circle) and between 23.5 degrees South and 60 degrees South (between the Tropic of Capricorn and the Antarctic Circle).
- terrestrial
-
Living on the ground.
- desert or dunes
-
in deserts low (less than 30 cm per year) and unpredictable rainfall results in landscapes dominated by plants and animals adapted to aridity. Vegetation is typically sparse, though spectacular blooms may occur following rain. Deserts can be cold or warm and daily temperates typically fluctuate. In dune areas vegetation is also sparse and conditions are dry. This is because sand does not hold water well so little is available to plants. In dunes near seas and oceans this is compounded by the influence of salt in the air and soil. Salt limits the ability of plants to take up water through their roots.
- tropical savanna and grassland
-
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
-
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
-
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.
- forest
-
forest biomes are dominated by trees, otherwise forest biomes can vary widely in amount of precipitation and seasonality.
- scrub forest
-
scrub forests develop in areas that experience dry seasons.
- 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.
- 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.
- polygynous
-
having more than one female as a mate at one time
- iteroparous
-
offspring are produced in more than one group (litters, clutches, etc.) and across multiple seasons (or other periods hospitable to reproduction). Iteroparous animals must, by definition, survive over multiple seasons (or periodic condition changes).
- year-round breeding
-
breeding takes place throughout the year
- sexual
-
reproduction that includes combining the genetic contribution of two individuals, a male and a female
- viviparous
-
reproduction in which fertilization and development take place within the female body and the developing embryo derives nourishment from the female.
- embryonic diapause
-
At about the time a female gives birth (e.g. in most kangaroo species), she also becomes receptive and mates. Embryos produced at this mating develop only as far as a hollow ball of cells (the blastocyst) and then become quiescent, entering a state of suspended animation or embryonic diapause. The hormonal signal (prolactin) which blocks further development of the blastocyst is produced in response to the sucking stimulus from the young in the pouch. When sucking decreases as the young begins to eat other food and to leave the pouch, or if the young is lost from the pouch, the quiescent blastocyst resumes development, the embryo is born, and the cycle begins again. (Macdonald 1984)
- altricial
-
young are born in a relatively underdeveloped state; they are unable to feed or care for themselves or locomote independently for a period of time after birth/hatching. In birds, naked and helpless after hatching.
- fossorial
-
Referring to a burrowing life-style or behavior, specialized for digging or burrowing.
- nocturnal
-
active during the night
- motile
-
having the capacity to move from one place to another.
- sedentary
-
remains in the same area
- social
-
associates with others of its species; forms social groups.
- tactile
-
uses touch to communicate
- acoustic
-
uses sound to communicate
- chemical
-
uses smells or other chemicals to communicate
- visual
-
uses sight to communicate
- tactile
-
uses touch to communicate
- acoustic
-
uses sound to communicate
- chemical
-
uses smells or other chemicals to communicate
- carrion
-
flesh of dead animals.
- ecotourism
-
humans benefit economically by promoting tourism that focuses on the appreciation of natural areas or animals. Ecotourism implies that there are existing programs that profit from the appreciation of natural areas or animals.
- herbivore
-
An animal that eats mainly plants or parts of plants.
- folivore
-
an animal that mainly eats leaves.
- frugivore
-
an animal that mainly eats fruit
- granivore
-
an animal that mainly eats seeds
References
Government of Western Australia, 2006. "Burrowing Bettong (Boodie)" (On-line). Department of Conservation and Land Management. Accessed November 14, 2006 at http://www.calm.wa.gov.au/plants_animals/pdf_files/sp_boodie.pdf .
Massicot, P. 2004. "Burrowing Bettong" (On-line). Animal Info. Accessed November 14, 2006 at www.animalinfo.org/species/bettlesu.htm .
Menkhorst, P. 2001. A field guide to the mammals of Australia . New York: Oxford University Press.
Meyers, P. 2001. "Potoroidae" (On-line). Animal Diversity Web. Accessed November 14, 2006 at http://animaldiversity.ummz.umich.edu/site/accounts/information/Potoroidae.html .
Robley, A., J. Short, S. Bradley. 2001. Dietary overlap between the burrowing bettong ( Bettongia lesueur ) and European rabbit ( Oryctolagus cuniculus ) in semi-arid coastal Western Australia. Wildlife Research , 28: 341-349.
Robley, A., J. Short, S. Bradley. 2002. Do European rabbits ( Oryctolagus cuniculus ) influence the population ecology of the burrowing bettong ( Bettongia lesueur )?. Wildlife Research , 29: 423-429.
Sander, U., J. Short, B. Turner. 1997. Social organisation and warren use of the burrowing bettong, Bettongia lesueur , (Macropodoidea: Potoroidae). Wildlife Research , 24: 143-157.
Strahan, R. 1983. The Australian Museum Complete Book of Australian Mammals . London: Angus & Robertson Publishers.