The nocturnal western ringtail possum is a folivorous marsupial (1), with a strong preference for peppermint leaves. Leaves from trees of the Myrtle family are a second favourite when peppermint foliage is unavailable (1), while jarrah and marri leaves are the main food source in the inland forests (3). Garden vegetation, such as leaves from rose bushes, is sometimes eaten in urban areas (1). The western ringtail possum is generally solitary during the day (2), when it takes shelter in tree hollows, where they are available, or in dreys (nests) that it constructs in dense vegetation using leaves and sticks (1) (5) (6). Any social activity takes place at night, when males may visit females in neighbouring home ranges (3). The western ringtail possum occupies a small and stable home range, although the size of the range varies depending on habitat quality and population density, and often overlaps with the home range of other individuals by up to 70 percent (1) (2).
Although reproduction takes place year round, the majority of young are born in late autumn and winter (1). This ensures lactation and weaning, which have a high nutritional demand, take place during the spring and summer when there is an abundance of new leaf shoots (3). Generally only one offspring is produced, although the litter size can vary between one and three young (1). Like all marsupials, immediately after birth the young crawls into its mother’s pouch where it remains until it is about three months old; the young then leaves the pouch but continues to suckle until it is six to seven months old (1) (2). When male western ringtails are seven months old (and weigh between 600 and 700 grams), they leave their mother’s range and gain independence (1), while female young generally remain in or adjacent to their mother’s range. Life expectancy in the wild is three to five years on average, although some individuals have lived beyond six years (3).