Potoroos digging for truffle-like fungi may eat fewer species as temperatures rise

Researchers analysed 23 years of long-footed potoroo scats and found that warmer conditions were linked with potoroos consuming fewer species of truffle-like fungi, which could affect fungal dispersal and tree–fungus partnerships.

Long-footed potoroos dig for underground, truffle-like fungi and help move fungal spores through their scats. Australia hosts hundreds of these truffle-like fungal species, many of which form nutrient-trading partnerships with native trees. The long-footed potoroo depends on these fungi for more than 90% of its diet and is an endangered species with a reduced range. New research used a rare 23-year scat collection to examine whether warming conditions are changing which fungi potoroos eat. Key findings: - Researchers used DNA analysis on potoroo scats collected from 1993–2016 to identify the species of truffle-like fungi consumed. - Warmer conditions were associated with potoroos eating fewer species of truffle-like fungi, a pattern seen across seasons and years. - During warm periods potoroos ate less of some fungal genera and relatively more of others, including Mesophellia. - Many truffle-like fungi form ectomycorrhizal partnerships with eucalypts and other native trees, exchanging nutrients with tree roots. - Because potoroos disperse spores in their scats, a narrower fungal diet could reduce opportunities for some fungi to spread and affect tree–fungus relationships. Summary: The study indicates rising temperatures are associated with narrower truffle-like fungal diets for long-footed potoroos, which could alter fungal dispersal and the ectomycorrhizal partnerships that support tree health. Undetermined at this time.