Eastern Bettongs are curious creatures. They use their prehensile tails to carry grass to their nests. They’re small in size, but they can hop one metre into the air. And, like many Tasmanians, they’re connoisseurs of fine food – a favoured delicacy in their diet is …truffles!
'Charasmatic little animals'
Kirstin Proft is enamoured by all things bettong. She’s a PhD student from the University of Tasmania. Kirstin is one of five students investigating how different native animals feed, move and avoid predators in the Midlands, a highly fragmented landscape. When she moved to Tasmania, she knew little about bettongs, also known as ‘rat kangaroos’. Two years later, after many long nights trapping the marsupial species, she describes them as ‘weird and wonderful things… charismatic little animals, each with their own personality’.
Bettongs and quolls
Kirstin studies two iconic Tasmanian animals: Eastern Bettongs and the Spotted-tailed Quoll. She wants to know how the species have been affected by habitat clearing and changes in land use.
Eastern Bettongs are important ‘ecosystem engineers’: their digging plays a key role in turning over topsoil in woodlands, and in maintaining plant and fungi species. Eastern Bettongs were once found across eastern Australia. But due to land clearing and the introduction of the feral cat and fox, the mainland population became extinct in the 1920s. The species is now restricted to Tasmania (and recent reintroductions in the Australian Capital Territory).
Spotted-tailed Quolls play an important ecological role – they are the second-largest native mammalian carnivore in Tasmania (after the Tasmanian devil). They were once relatively abundant on the mainland, but are now listed nationally as Endangered. The species is still found throughout Tasmania, which is considered an important stronghold.
Both species need vegetation cover to move from place to place. But the Midlands landscape is highly fragmented: ‘islands’ of native woodland and grasslands are surrounded by a sea of sheep paddocks and cultivated fields. In the last few years, an increase in pivot irrigation is making these gaps even greater. Kirstin asks: how big do these gaps have to be before animals no longer ‘cross the paddock’?
Kirstin - the mad geneticist!
Kirstin also describes herself as ‘the mad genetics person in the group’. Of the five students researching the Midlands, she is the only person studying genetics.
Kirstin has gathered tissue samples from bettongs that live across the Midlands. She sets traps in woodland patches and takes small biopsies from the ear of any captured animals. She also using tissue samples gathered by Rowena and Riana during their research. In addition, she is analysing quoll and bettong samples collected from populations scattered across Tasmania by researchers in the past decade.
She takes these samples back to the lab for genetic analysis. By sequencing the DNA in the samples, she can obtain a unique genetic fingerprint (or “genotype”) for each animal. From this, she can see how closely related different animals are, and how the species has evolved. Basically, Kirstin is constructing family trees of bettongs and quolls in the Midlands!
Most importantly, Kirstin’s work will highlight where patches are so disconnected that bettongs and quolls no longer travel between them. This helps groups like Bush Heritage and Greening Australia to know where we should protect and replant habitat. Together, we’re working towards a landscape where our native animals can find the tastiest truffles…and the most attractive mate!
Kirstin’s research is one part of a collaboration between the University of Tasmania, Greening Australia, Bush Heritage, the Tasmanian Land Conservancy, the Tasmanian Government and committed landholders.
Tomorrow we’ll profile Riana Gardner, who studies the movements of individual bettongs.
- Kate Cranney, Science Communicator Intern.