Diet of the quokka (Setonix brachyurus) (Macropodidae:Marsupialia) in the northern jarrah forest of Western Australia

The diet of the quokka in the northern jarrah forest of Western Australia was investigated by microscopic examination of faecal pellets of known individuals and comparison with a reference collection of plant epidermal tissue. Twenty-nine plant species were identified from the 97 faecal pellet groups collected from 53 individuals, confirming that the quokka is a browsing herbivore that favours leaves and stems. Of those 29 species, 11 made up over 90% of the diet and five species accounted for 71%. Thomasia species were the most common in the diet and the most preferred; Dampiera hederacea was also preferred and these species, along with Bossiaea aquifolia, Mirbelia dilatata and Agonis linearifolia, were the five most important food items. The seasonal variation in the diet of the quokka, and that between sites, can be attributed to increases in nutrient content associated with fresh growth associated with season or vegetation seral stage after fire. The reduced dietary diversity at sites with younger seral stages ( 25 years after fire) age classes. The relatively short availability of sufficient, high-quality, succulent plants in the seral succession of swamps occupied by quokkas is likely to drive a regular pattern of local extinction and recolonisation.