Bilbies are important ecosystem engineers.
The Bilby is an excellent digger – they can shift more than 1.5 tonnes of soil per kilogram of body mass in a year as they construct and maintain complex burrows up to three metres long and two metres deep! These burrows often provide a home for other animals like insects, reptiles, birds and small mammals, and are a source of shelter from predators and high summer temperatures. Every year bilby populations continue to decline and they are under threat of extinction due to introduced predators (cats and foxes), inappropriate fire regimes, and the impacts of grazing and landclearing. Competition with introduced animals is another major threat as domestic stock like cattle and sheep eat the same plants. Rabbits also compete with Bilbies for their food and burrows. There may be much more at stake than the survival of bilbies themselves – as well as providing accommodation for others, bilbies improve soil health by turning the soil over, mixing through organic matter and bringing deep soils and their nutrients to the surface. Their diggings provide sites for water to penetrate the soil and for the spread of important mycorrhizal fungi (which help plants to absorb nutrients and cope with Australia’s nutrient-poor soils) across the landscape.