Summary: | Many Australian mammal species have experienced a severe decline in range and abundance over the last 200 years. Conservation of threatened mammals involves conservation of habitat and food resources. Mycorrhizal fungi produce spore-laden sporocarps, which are consumed by many ground dwelling mammals. This interaction is called mycophagy. Clearly, fungal resources are of fundamental importance to the conservation of many mammal species in Australia. The plant pathogen Phytopthora cinnamomi has catastrophic effects on ecosystems in the Jarrah forest of Western Australia. The effects of the pathogen on flora have been extensively studied, but it's effects on mammal communities in these ecosystems has not been measured. This study investigates differences in mycophagy between P. cinnamomi affected and healthy Jarrah forest ecosystems. This was achieved by investigating relationships between measured environmental variables, fungal productivity and mycophagous tendencies at three site types in the Darling Range, near Dwellingup. A trend was apparent between biomass and diversity of hypogeous fungi between sites. Sites of low impact had the highest number of hypogeous fungi species, plus the greatest biomass of sporocarps. Sites exhibiting high P. cinnamomi impact had significantly reduced hypogeous fungal biomass and diversity. Significant differences were evident in mycophagy between Phytophthora affected ecosystems. However, this study was unable to draw definitive conclusions due to the complex nature of interactions, and differences among sites. For example, environmental variables such as litter biomass had large standard deviations, suggesting sampling effort required was very high. Clearly, longer term surveys are required to provide definitive conclusions. Trends in mycophagy were evident as a function of season. This study identified fungal utilisation by previously undocumented mycophagous mammals. Sites with medium P. cinnamomi impact had the greatest degree of mycophagy. High and Low impact sites showed similarities in the number of spores in scats. Dasyurus geoffroii consumed the greatest diversity of fungal taxa, and had the greatest number of spores in the scats. Rattus rattus consumed the second greatest number of spores, and Sminthopsis gilberti, Mus musculus and Antechinus flavipes consumed similar, low numbers of spores. The number of spore types however, was high in A. flavipes, S. gilberti and M. musculus. R. rattus exhibited very low diversity of spores in scats, however, these spore types were in high occurrence.
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