Bilby

Lore & Background

The genus name *Macrotis* means 'big-eared' in Greek, referring to the animal's large ears. The family name Thylacomyidae derives from an invalid synonym *Thylacomys*, meaning 'pouched mouse'. The term 'bilby' is a loanword from the Yuwaalaraay Aboriginal language of northern New South Wales, meaning long-nosed rat; it is also known as *dalgite* in Western Australia and *pinkie* in South Australia. Bilbies are desert-dwelling marsupial omnivores of the order Peramelemorphia. At European colonisation, two species existed; the lesser bilby became extinct in the 1950s, while the greater bilby survives as a vulnerable species. The greater bilby averages a certain length excluding its tail, which is also of a notable length. Its fur is grey or white, with a long, pointed nose and very long ears that radiate heat, giving it a rabbit-like nickname. Compared to bandicoots, bilbies have a longer tail, larger ears, and softer, silkier fur. They are nocturnal and do not need to drink water, obtaining moisture from food such as insects, larvae, seeds, spiders, bulbs, fruit, fungi, and very small animals. Food is found by digging or scratching in the soil, using their long tongues. Unlike bandicoots, bilbies are excellent burrowers, using strong forelimbs and claws to build extensive tunnel systems. A bilby typically makes up to about a dozen burrows within its home range, moving between them for shelter from predators and heat. The female’s pouch faces backwards to prevent dirt entering while digging. Gestation lasts about 12–14 days, one of the shortest among mammals.

Reader's Guide

Bilbies are desert-dwelling marsupial omnivores, members of the order Peramelemorphia. At European colonisation, two species existed; the lesser bilby became extinct in the 1950s, while the greater bilby remains endangered and is listed as vulnerable. The greater bilby averages 55 cm in length, with a tail of about 29 cm. Its fur is grey or white, and it possesses a long, pointed nose and very long ears, which radiate heat and enhance hearing. As nocturnal omnivores, they obtain all moisture from food—insects, larvae, seeds, spiders, bulbs, fruit, fungi, and very small animals—and do not need to drink water. They locate food by digging or scratching in soil, using their long tongues. Unlike bandicoots, bilbies are excellent burrowers, constructing extensive tunnel systems with strong forelimbs and claws. A bilby typically maintains up to a dozen burrows within its home range, moving between them for shelter from predators and daytime heat. The female’s pouch faces backward to prevent dirt from entering while digging. Gestation lasts about 12–14 days, among the shortest of any mammal. The bilby lineage extends back 15 million years; a 2014 discovery of a 15-million-year-old fossil jaw showed shorter teeth suited for eating forest fruit, whereas modern bilbies have evolved long teeth for digging desert soil to find worms and insects. The bilby is thought to have diverged from a carnivorous bandicoot ancestor 20 million years ago. Conservation efforts include a national recovery plan involving captive breeding, population monitoring, and reintroduction into former habitats, such as the Arid Recovery Reserve in South Australia (2000) and Currawinya National Park in Queensland (2019). Reintroductions have also succeeded on the Peron Peninsula in Western Australia and at sanctuaries like Scotia and Yookamurra. A breeding program at Kanyana Wildlife Rehabilitation Centre near Perth has been highly successful. The bilby has become a cultural symbol as a native alternative to the Easter Bunny, with chocolate Easter Bilbies sold, sometimes with profits directed to protection and research.

Did You Know?

• The bilby's gestation period of 12–14 days is one of the shortest among mammals.
• The female bilby's pouch faces backwards to prevent dirt from entering while she digs.
• The lesser bilby became extinct in the 1950s.