Scientists are using DNA from poop to save the world's rarest marsupial, the Gilbert's potoroo. This critically endangered species, found only in Western Australia, has fewer than 150 animals left in the wild. Researchers from Edith Cowan University (ECU) and the Department of Biodiversity, Conservation and Attractions (DBCA) are working together to better understand the potoroo's diet, so conservation teams can identify suitable new habitats and help secure the species' future.
The challenge was trying to determine what the potoroo eats and where those resources can be found. Traditionally, researchers would go through undigested material in scats to study animal diets, but trying to identify fungal spores remained a challenge. This research used a molecular technique, known as eDNA metabarcoding, to decipher what animals are eating. It's a non-invasive way of studying diet and all you need are fresh scats from the environment.
The team also examined whether the diets of more common fungi-eating mammals overlapped with the Gilbert's potoroo. Researchers focused on species that historically shared the same habitats. They found that there was some overlap in the diet of the four mammals, and that habitat use between the quokka and potoroo were also really similar. Based on their results, they recommend focusing on areas where all three species persist together as an indicator of suitable food, or habitat, for future potoroo translocation sites.
Gilbert's potoroo was once believed to have disappeared entirely before being rediscovered in 1994. Since then, conservation teams have tried several approaches to increase the population. Soon after their rediscovery, breeding them in captivity was tried, but that didn't work out, particularly because of how picky they are with their food resources. This is why wild-to-wild translocations are so important. In 2015, a bushfire destroyed 90 per cent of core potoroo habitat in Two Peoples Bay, which is home to the only natural population of Gilbert's potoroo. Fortunately, insurance populations had been established on Bald Island and in a fenced enclosure at Waychinicup National Park by DBCA.
The search for new translocation sites is an important next step in the recovery of Gilbert's potoroo from near extinction. This publication shows that examining the fungal diet of mammals that occur with the potoroo can help in deciding where to establish new populations. Fungi-eating mammals are ecosystem engineers -- they dig for fungi which helps in soil turnover, and they act as vectors for fungal spore dispersal. Fungi have several ecological functions, including having mutually beneficial relationships with plants, so mycophagous mammals are really important in maintaining healthy ecosystems. Unfortunately, many of Australia's mammals are threatened because of predation from introduced cats and foxes. That is why it is vital that we do everything we can to help protect our native wildlife, and translocations are one important way to accomplish that goal.
