The Birriliburu Indigenous Protected Area (IPA), Martu Country, Western Australia, is about the size of Tasmania - 6.6 million hectares of vast and diverse beauty. Living in this ecosystem are one of the continent’s most celebrated, yet rarely seen marsupials, Mantangalku. Mantangalku is the Martu word for the Greater Bilby (Macrotis lagotis).
Since European settlement, Mantangalku have disappeared from much of their previous range and are now only found in arid and semi-arid areas.
In good news, the rangers recently captured a photo of the Bilby on a remote sensor camera after it had eluded them for two years – just in time for Easter!
The Birriliburu Rangers have a big job. The sheer scale of the IPA and the task of trying to care for its Bilby inhabitants comes with immense responsibility. The Bilby, like many other native animals has cultural significance for Martu.
Here are some facts about the Greater Bilby, and reasons why the rangers are working so hard to protect it. Move aside Easter Bunny, let’s make way for the Bilby!
1. They used to be (almost) everywhere!
Most people aren’t lucky enough to have come face to face with a Greater Bilby. They’re extremely rare, nocturnal, and shy. As with many other native mammals, their range has dramatically shrunk since European settlement.
The Bilby once lived on 70% of the continent. Now, they inhabit parts of Tanami Desert of the Northern Territory, the Great Sandy Desert, parts of the Pilbara and Kimberley (near Broome) regions of Western Australia, the clay and stony soils of the Mitchell grasslands of southwest Queensland, and where the Birriliburu IPA is, the Little Sandy and Gibson Deserts.
2. The Lesser Bilby is extinct
We refer to the Greater Bilby simply as ‘the Bilby’, but it once had a relative, the Lesser Bilby (Macrotis leucura). Due to large-scale land clearing and predation from invasive cats and foxes, it is believed to have been extinct since the 50s. Specimens were formally recorded just six times, so little is known about the species.
3. They make LOTS of burrows
Bilbies make a new burrow every month or so. Some are for sleeping, and others specifically to escape from predators. Bilbies are known as ecosystem engineers, shifting soil through their digging which improves soil health. They use their large claws to rapidly dig, often sealing the burrow behind them to block the entrance from predators and to keep the temperature at a constant 23 degrees Celsius.
Even despite these cunning defences and evolved expertise, they’re constantly under threat from predation from cats, foxes and dingoes. Keep on digging, Bilbies!
4. They have interesting neighbours
On Birriliburu, Bilbies have been recorded in the same arid ecosystems as Night Parrots (Pezoporus occidentalis), Marsupial Moles (Notoryctes typhlops) and Great Desert Skink’s (Liopholis kintorei). These landscapes are incredibly important habitats and despite harsh climatic conditions, are far from empty. Bush Heritage have been partnered with the Birriliburu Rangers since 2013, assisting with fire ecology, right-way science and fauna monitoring across this important ecosystem.
5. Bilbies have very good hearing
Bilbies have large ears and subsequently, great hearing. Their hearing and strong sense of smell are very important for the Bilby when finding food and detecting predators. On Birriliburu IPA the Bilbies use these senses to find one of their favorite foods, Lunki (witchetty grubs). Lunki are found in the roots of many trees. Their ears aren’t just for hearing, they are also a tool for thermoregulation, drawing out heat from the rest of their bodies.
On the Birriliburu IPA, rangers are experts in tracking and finding burrow systems and identifying Bilby habitat. They go out every year to monitor Bilby burrows. Efforts to control invasive predators are amping up with the use of targeted Felixer machines, which use rangefinder sensors to distinguish target cats and foxes from non-target wildlife and humans.
There are many more reasons we need to safeguard the beautiful Bilby from increasing threats.