Words by Theresa Bint
Many folk would be aware that mushrooms are the fruiting body or spore-bearing part of a fungus with the vegetative part – the mycelium – being a fine network of fungal hyphae occupying the soil, wood, mulch or preferred substrate.
Most terrestrial fungi use air currents to disperse their spores; animals (vertebrate and invertebrate) are also agents of dispersal, carrying spores on their bodies or passing them through their digestive tracts.
Truffles are hypogeous (underground) mushrooms with their spores on the inside. Having no access to air currents (and because their spores are relatively large), they rely on animals to spread the spores.
Bandicoots love truffles! They can detect the aroma of a truffle through several centimetres of soil. The fungi contain proteins and fats and are a valuable food source for many marsupials, including potoroos and bettongs. The fungal spores remain viable – and may have enhanced viability – after passing through the bandicoot’s digestive tract.
Native truffles look like lumpy, roughly spherical pebbles in various shades of white, red, pink, yellow, brown and purple and are about 10 – 30 mm in diameter.
In Australia, there are around three hundred species of native truffle recorded, with estimates of the actual number of species above 2000. Like the gourmet truffles that fetch astronomical prices around the world, Australian native truffles are mycorrhizal, forming symbiotic relationships with trees and shrubs including eucalypts, casuarinas and melaleucas.
Animals whose diet consists of a large proportion of truffles tend to be small with relatively energy efficient means of locomotion – like the hopping gait of bandicoots, bettongs, potoroos and pademelons. These creatures have lower energy requirements and can travel relatively long distances – making them ideal for fungi spore dispersal.
Spores are dispersed, more mycorrhizal relationships are established, plants get enhanced access to water and nutrients and vulnerable seedlings are nourished and protected. Bandicoots, through their love of truffles, enhance ecosystem resilience.