Scientists from Royal Botanic Gardens Victoria and the University of Melbourne have uncovered evidence that climate change may already be affecting truffle-like fungi relied upon by the Potorous longipes (Long-footed Potoroo) — with potential consequences for the underground networks that sustain Australian forests. 

Dr Camille Truong, Research Scientist (Mycology) at Royal Botanic Gardens Victoria, said truffle-like fungi — and fungi more broadly — play a critical yet largely overlooked role in sustaining Australian ecosystems. 

“Truffle-like fungi are an important food source for numerous Australian animals and assist trees with water and nutrient uptake, while also protecting them from environmental stress and disease,” Dr Truong said. “They form part of vast underground networks that we still know very little about. If these species disappear before they are properly identified, we lose the opportunity to conserve them and understand the benefits they provide.” 

Australia is recognised as a global hotspot for truffle-like fungi, yet only around 1,500 species — approximately 20 per cent — have been formally described. Globally, scientists estimate that less than ten per cent of all fungi species are currently known to science. 

Unlike mushrooms, which produce visible fruiting bodies above ground, truffle-like fungi develop entirely underground. 

“We cannot see them, yet they are vital to the health of Australia’s temperate forests and woodlands,” Dr Truong said. “Trees such as Eucalypts depend on these fungi for resilience, nutrient exchange and survival under changing environmental conditions.” 

Because truffle-like fungi grow underground, they rely on animals rather than wind or water to disperse. Native mammals detect their scent, dig them up, consume them and disperse fungal spores through their scats, helping maintain healthy forest systems. 

The newly published study analysed scats from the Long-footed Potoroo collected over a 23-year period. The Long-footed Potoroo — one of Australia’s most specialised fungal feeders — derives around 90 per cent of its diet from fungi. 

The research led by PhD student Emily McIntyre from the University of Melbourne, found the small marsupial consumed a narrower range of truffle species during warmer conditions, suggesting climate change may already be reducing fungal availability and threatening both species’ survival. 

“There is a triangle of dependability here,” Dr Truong said. “The fungi rely on the Potoroo to disperse their spores, the Potoroo relies on fungi for survival, and trees rely on fungi for growth and resilience and to buffer the impacts of climate change.” 

Truffle-like fungi thrive in cool, moist environments, making them particularly vulnerable to rising temperatures and drier conditions. 

“A hotter and drier climate can dry out fungal networks underground, inhibit growth, increase competition and reduce the sugars supplied by host trees,” Dr Truong said. 

Despite their ecological importance, many fungi remain invisible to the human eye, with a single handful of soil capable of containing hundreds of fungal species. Advances in DNA sequencing are accelerating species discovery; however researchers say urgent work is still needed. 

“Interestingly, Potoroos are often better than humans at detecting truffle-like fungi, meaning their scats are invaluable for discovering new species,” Dr Truong said. 

She added that protecting fungi requires a holistic approach to ecosystem conservation, recognising the interconnected relationships between soil biodiversity, wildlife and forests. 

“We must avoid creating empty forests — landscapes that appear intact but have lost the biodiversity that keeps them functioning.” 

Australian animals known to specialise in fungi consumption include Potoroos and Bettongs, while generalist feeders include Bandicoots, Quokkas, Wallabies and Possums. 

Ectomycorrhizal fungi form extensive underground networks that create symbiotic relationships with trees, effectively extending root systems to access otherwise unavailable nutrients and water, protect against pathogens and help buffer environmental change. In return, fungi receive sugars produced by the tree through photosynthesis, storing an important amount of carbon below ground.