MYCOPHAGY IN SMALL MAMMALS - A COMPARISON OF THE OCCURRENCE AND DIVERSITY OF HYPOGEAL FUNGI IN THE DIET OF THE LONG-NOSED POTOROO POTOROUS-TRIDACTYLUS AND THE BUSH RAT RATTUS FUSCIPES FROM SOUTHWESTERN VICTORIA, AUSTRALIA
Mk. Tory et al., MYCOPHAGY IN SMALL MAMMALS - A COMPARISON OF THE OCCURRENCE AND DIVERSITY OF HYPOGEAL FUNGI IN THE DIET OF THE LONG-NOSED POTOROO POTOROUS-TRIDACTYLUS AND THE BUSH RAT RATTUS FUSCIPES FROM SOUTHWESTERN VICTORIA, AUSTRALIA, Australian journal of ecology, 22(4), 1997, pp. 460-470
Three broad dietary categories-fungus, plant and arthropod-were identi
fied from faecal samples of two species of small terrestrial mammal in
forest vegetation in southwestern Victoria. Fungal material formed th
e major component of the diet of the long-nosed potoroo Potorous trida
ctylus throughout the year and of the bush rat Rattus fuscipes during
autumn and winter. Fungal material was most abundant for both species
during autumn and winter and significantly less common in spring and s
ummer. These results confirm previous studies which found P. tridactyl
us to be highly mycophagous throughout the year and R. fuscipes to be
strongly mycophagous seasonally. Particular consideration was given to
the composition of fungi in the diet. Fungal spores in faecal materia
l were assigned to spore classes, which represent one or more fungal s
pecies that have similar spore morphology. Twenty-four fungal spore cl
asses were recorded, but for both animal species most of the fungi con
sumed were hem seven major spore classes. The proportions of major spo
re classes in the diet of both animals were generally similar, even th
ough the composition of spore classes differed markedly across seasons
. Minor differences between species in the fungi consumed may be relat
ed to differences in selectivity, foraging, or microhabitat use. If fu
ngal resources are limiting, competition for such resources may be imp
ortant in this and other small mammal communities. The amount and dive
rsity of hypogeal fungi consumed by the two animal species makes them
both important spore dispersal agents in forest ecosystems. The capaci
ty of R. fuscipes and other seasonally mycophagous mammals in this rol
e may be more important than previously recognized, especially in habi
tats where species of the Potoroidae are absent.