Hypogeal fungi in the diet of the long-nosed potoroo (Potorous tridactylus) in mixed-species and regrowth eucalypt forest stands in south-eastern Australia

Abstract

The diet of the long-nosed potoroo (Potorous tridactylus), a medium-sized ground-dwelling marsupial, was monitored (using faecal analysis) in a multiaged eucalypt forest site, and a regrowth eucalypt forest site in south-eastern Australia. In the multiaged forest P. tridactylus was primarily mycophagous, consuming the sporocarps (fruiting bodies) of at least 58 fungal species. Most of these taxa were hypogeal (underground fruiting) basidiomycetes thought to form mycorrhizae on the roots of a variety of plants. The percentage occurrence of fungus in faeces decreased in spring and summer and increased in autumn and winter. This pattern was opposite to the changing occurrence in faeces of other food types, and the percentage occurrence of spores of a major fungus species. At the regrowth forest site the quantity of fungus in faeces of P. tridactylus was lower but more constant over time. There were also differences in the percentage occurrence of spores of at least two fungal species. Additionally, the diversity of fungal taxa found as spores in faeces at the regrowth site was significantly lower (on average) than that recorded in faeces from the multiaged site. Differences in the fungal diets of the two P. tridactylus populations may be partially attributable to the disturbance (fire and logging) histories of each site.