The mountain pygmy possum is best described as an omnivore-insectivore-granivore- frugivore. While eating habits of B. parvus are diverse, the diversity of prey is low, making B. parvus a specialized feeder, according to the season. During the 'active season' from October-April, B. parvus' diet contains high energy food. During this period, B. parvus is an omnivore and insectivore, feeding heavily upon the Bogong moth (Agrotis infusa), which migrates yearly to the Australian alps for breeding. The yearly migration of the moth provides a predictable, energy rich and abundant food supply for B. parvus. Studies conducted by Mansergh and associates (1990) reveal that the Bogong moth constitutes over 33% of the total 'active season' diet of B. parvus. A later study by Smith and associates (1992) reported that the moth may actually be the only dietary item during the reproductive season (October-December) of B. parvus. It has been found that females take a higher percentage of Bogong moths than males, due to the concurrent breeding season and additional nutritional supplements required to raise offspring (Smith and Broome 1992). Other insects, consumed in sparse quantities, are caterpillars, millipedes, beetles and spiders (Broome and Mansergh 1994). As the active season progresses, the abundance of Bogong moths decreases, leading to a dietary switch from moths to seeds and berries. The mountain pygmy possum prefers the seeds of habitat specific species such as Mountain Plum-pine, Rambling Bramble, and Snow Beard-heath, during the months of January-April (Broome and Mansergh 1994).
During the 'non-active', or hibernation season, B. parvus caches seeds and berries, which constitute over 75% of their diet from May-October (Broome and Mansergh 1994). The mountain pygmy possum is the only marsupial found to cache non-perishable food items (Menkhorst 1995).
Burramys parvus is well adapted to its specialized diet. The mountain pygmy possum has agile forelimbs that permit manipulation of seeds, berries and insects. The hard coats of seeds and insect exoskeletons are easily opened with a plagiaulacoid premolar. Burramys parvus uses its procumbent lower incisors to scoop out the interior of the seed or insect.