Bettongia lesueur
burrowing bettong

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. (Government of Western Australia, 2006)

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. (Sander, et al., 1997)

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. (Massicot, 2004; Strahan, 1983)

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. (Meyers, 2001)

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. (Massicot, 2004)

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. (Government of Western Australia, 2006)

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. (Massicot, 2004)

There is little information on the lifespan of B. lesueur, but it is known to usually live three years in the wild. (Government of Western Australia, 2006)

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. (Sander, et al., 1997; Strahan, 1983)

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 (Strahan, 1983)

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. (Sander, et al., 1997; Strahan, 1983)

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. (Massicot, 2004)

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. (Menkhorst, 2001)

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. (Strahan, 1983)

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. (Strahan, 1983)

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). (Robley, et al., 2001; Robley, et al., 2002; Strahan, 1983)

Burrowing bettongs may be an ecotourism draw because of their rarity.

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. (Massicot, 2004)

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. (Government of Western Australia, 2006)

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. (Massicot, 2004; Strahan, 1983)

This species is sometimes called Bettongia lesueuri. (Strahan, 1983)