Two endangered marsupials are being reintroduced into the Shark Bay World Heritage Area in order to promote species conservation and ecosystem restoration. A new study from Edith Cowan University (ECU) confirms that the presence of fungal food resources is important to support this effort.The study, published in the journal Ecosystems, was led by Rebecca Quah, a doctoral candidate at Edith Cowan University, at six sites across Western Australia and the Northern Territory, including Dirk Hartog Island in Shark Bay. Scientists used DNA technology to decipher which fungi were palatable to marsupials (burrowing betong) and marsupials (brush-tailed betong). Then check the availability of key food resources to support the new inhabitants of the island.What makes these bets special is that they spend much of their waking hours, digging in the soil, either searching for food or burrowing for shelter in case a buddy is present. “Among the nutrients these betongs eat are fungi, a feeding habit known as mycelium. As they burrow and feed on the fungi, they do something crucial to the landscape – turning up the soil and spreading fungal spores, which helps keep the plants and broader ecosystem healthy,” Quah said.
Once original, now no more
After the successful removal of livestock and feral cats, the island is now in the recovery phase, with scientists introducing bobcats and wild cats.
Dirk Hartog’s island wasn’t always this way. Between the 1860s and 2009, pastoral activity dramatically changed the island’s landscape, and along with the effects of predation by introduced feral cats, at least 11 native species, including the buddy, the willie, and the Shark Bay shark, disappeared. Cats were brought by European shepherds and lighthouse keepers in the 19th century as household pets and to control vermin.
Over time, some cats escaped or were allowed to reproduce, eventually creating feral populations that wiped out local marsupial and bird populations.After the successful removal of livestock and feral cats, the island is now beginning to recover, with scientists actively working to rebuild its animal population. “Before reintroducing the boodie and woylie species, we needed to know whether the mysterious fungal resources these species depend on persisted during natural changes on the island,” Quah said.Fungi spend most of their lives hidden underground as networks of thread-like structures. “The mushroom fruiting bodies we see are just the tip of the iceberg, and some fungal fruiting bodies never appear above ground at all.” Traditional methods for studying fungal communities have presented many challenges; However, molecular technology has changed everything.Instead of looking at the content of stool and intestines to manually identify undigested nutrients, the team used DNA technology.
“First, we analyzed DNA from the faeces of organisms at five sites across Western Australia and the Northern Territory,” Quah said. Just like fingerprints, DNA sequences help scientists identify each fungal species that bettongs eat.“We then collected soil samples from the dominant habitat types across Dirk Hartog Island and similarly analyzed DNA in the soil, which allowed us to find out what fungi are present on the island.”Finally, they compared the two data sets. The results showed that the island is home to 75 different species of fungi that produce larger, more visible fruiting bodies that animals are more likely to seek out.“Importantly, approximately 50 percent of the fungi consumed by the fungi at other sites are present on Dirk Hartog Island, including truffle-like species of the Pezizaceae family, which were more abundant in both the diet of the buddy and the willie, as well as on the island.”
Improvement in Fungal biodiversity
Bodies and wilis are not merely passengers in the ecosystem, but because they consume and excrete fungal material, their movement through the habitat facilitates the spread of fungi. “We have identified that the majority of boodie and woylie diets consist of ectomycorrhizal fungi, which are important in plant nutrient uptake, carbon cycling, and enhancing overall ecosystem productivity,” Quah said.“Some fungi, in particular, those that fruit underground, have also evolved to rely heavily on animals such as bettong to spread by developing an aromatic property to attract these animals,” she added. Without bodies and wellies on the island, the spread of these fungi will be limited and have a negative impact on plant communities.“We hope that the reintroduction of these stakes will not only contribute to their conservation, but will also restore ecological functions that have been largely absent for decades on Dirk Hartog Island,” Quah said.
