Greater bilby - wwf - Australia

Species Fact Sheet:Greater bilby© WWF, KLEIN & HUBERTGreater bilbyMacrotis lagotisThe greater bilby is an iconic threatened marsupial that historically occurred across 70 per cent of continentalAustralia but has declined dramatically since European settlement. Now it is restricted to drier desert areas inthe Northern Territory and Western Australia and to a small corner of south western Queensland and is beingreintroduced to selected locations in South Australia and New South Wales. The species is culturally importantto many Indigenous people, and was formerly a valuable food resource.Bilbies are about the size of a small cat and have soft, blue-grey fur with white under parts and a distinctivewhite-tipped tail. They have long, highly sensitive ears and a pointed snout. Their forelimbs have three clawedtoes and two un-clawed toes that enable them to burrow effectively. Mature males tend to weigh double thatof mature females and have longer canines and a noticeably enlarged forehead.Conservation statusThe World Conservation Union (IUCN) Redlist of Threatened Species:VulnerableAustralian Government - Environment Protection and Biodiversity Conservation Act 1999:Vulnerable

Did you know?• The greater bilby is the only surviving member ofthe sub-family Thylacomyinae (family Peramelidae).• In captivity, bilbies have been known to live up to10 years of age.• Despite their sharp sense of hearing and smell,greater bilbies have relatively poor eyesight.Distribution and habitatMost bilbies live in sandy desert areas in spinifex (Triodiaspecies) grasslands. They dig large burrows up to twometres deep in sandplain country, where they live eithersingly or in pairs. They also seem to favour freshly burntcountry where there are more plentiful supplies of preferredfoods. According to the National Recovery Plan, bilbies liveamong three major vegetation types:• Open tussock grassland (both grasses and forbs)growing on uplands and hills,• Mulga woodland/shrubland (both pure mulga andmixed stands of mulga/witchetty bush) growing onridges and rises, and• Hummock grassland growing on sand plains anddunes, drainage systems, salt lake systems andother alluvial areas.Currently there are two distinct geographic areas occupiedby bilbies. One extends from the western deserts region(Tanami, Great Sandy, Gibson) of the Northern Territory andWestern Australia west to the Pilbara. The second is in thechannel country of south west Queensland.Ecology and life cycleBilbies forage mostly at night. They like to eat a mix of plantfood (bulbs and seeds) along with termites, ants, beetles,insect larvae, witchetty grubs and spiders, most of whichthey dig up with their strong front legs. One of the bilby’sfavourite plant foods is the bush onion or yalka (Cyperusbulbosa) that grows in desert sandplains after fires. Thebilby uses its long thin tongue to lick food from the ground,which results in up to 90 per cent of its waste being madeup of sand.A bilby burrow does not appear to contain a nest chamberor any nesting material; instead it is used mainly for shelterduring daylight hours and intermittently at night for rest andrefuge from predators and temperature extremes. Within itshome-range a single bilby may have over a dozen regularlyused burrows, some of these containing multiple entrances.By looking for residual hair from native mammals in thescats of cats and foxes it is possible to measure the impactthey are having on our native species. Recent research inthe Tanami Desert has shown bilby fur in roughly three percent of the cat scats examined. It seems remaining bilbypopulations in some desert areas are able to persistalongside fairly high levels of foxes and cats, probably as aresult of favourable fire regimes in the region. Theseregimes can create enough high-quality food resources sobilbies do not need to spend long hours above groundlooking for food.Competition with introduced herbivoresBilbies are forced to compete with introduced species suchas camels, cattle and rabbits. These species compete forfood resources as well as damaging the soils whereburrows are located. Camels occur throughout the range ofbilbies whereas cattle are more restricted in their impact (inQueensland only).Unsuitable fire regimesSome of the vegetation making up a large portion of thegreater bilby’s diet appears to rely heavily on the incidenceof fire to regenerate. Large uncontrolled fires may eventuallyreduce the type and abundance of food plants available tothe bilby.Drought & climate changeThe greater bilby is only partly adapted to aridenvironments and thus could be at risk of local extinctionsduring severe droughts. Changing weather conditionsbrought about by climate change also have the potential tonegatively affect the bilby’s food sources, further adding tothe decline of populations.Conservation ActionThere are many recovery projects in progress. Theseinclude breeding bilbies for release into fenced areas orpredator-free islands at Venus Bay and Roxby Downs inSouth Australia, Uluru-Kata Tjuta National Park in theNorthern Territory, Shark Bay and Dryandra Woodland inWestern Australia, and Currawinya in Queensland.Aboriginal people in the Gibson and Great Sandy Deserts inWestern Australia and the Northern Territory’s TanamiDesert are working alongside scientists and Land Councilstaff to survey and monitor wild bilby populations. WesternAustralia’s Department of Conservation and LandManagement is also developing fox and cat baitingmethods and running baiting trials in several bilby habitatareas across the country.In addition the Australian Government recently launchedNational Bilby Day, which is held annually on thesecond Sunday in September to raise awareness about theplight of bilbies and other threatened species.The greater bilby appears to have a polygamous matingsystem where sexually mature males mate with multiplefemales. Females have a backward opening pouch witheight teats. A healthy female can produce four litters peryear with one to three young to a litter. Gestation takesaround 14 days, then the young remain inside the pouchfor approximately 75–80 days. After emerging from theirmother’s pouch the young remain in the burrow for abouttwo weeks while the adults return regularly to feed them.ThreatsPredationFeral cats and foxes, wild dogs and dingos are known toprey on both young and adult bilbies. The risk of predationis thought to be greater following large wildfire events whenbilbies have to range further from home burrows to searchfor food.How you can help• Contact the Save the Bilby teamand donate your time (if you live insouthern Queensland) or to make afinancial contribution atwww.savethebilbyfund.com• Protect remnant bush in yourcommunity or on your land to helpprovide habitat for all our native animals,including the bilby• Support National Bilby DayWWF-Australia GPO Box 528 Sydney NSW 2001 Tel: 1800 032 551 wwf.org.au© 1986 Panda symbol WWF. ® (trademark words, e.g. “WWF”, “panda”, or “living planet”) is/are WWF Registered Trademark/s.