This largely nocturnal marsupial feeds primarily on a variety of insects and other invertebrates as it forages in trees and bushes (5), but will consumes fruit. Research suggests that the monito del monte may disperse the seeds of 80 percent of the surrounding plants that have fleshy fruits (6), as the seeds pass through the monito’s gut undamaged, and thus this small animal plays a vital role in the temperate forests it inhabits (4). Additionally, it is the sole seed disperser of the mistletoe Tristerix corymbosus; the seeds of this mistletoe must pass through the gut of the marsupial for germination to take place and for the development of a ‘holdfast’, which enables the plant to adhere to a host tree (6). The future of the mistletoe is therefore intrinsically linked to that of the monito del monte.
Monito del montes reportedly live in pairs, at least during the breeding season (2). The monito mates in late winter to early spring, and females give birth in early November (7). The size of the litter is limited by the number of teats, and so the average litter size is two to four. The young remain in the pouch, firmly affixed to the mother’s teats for the first two months of life. From late December, the young will begin to leave the pouch for short exploratory excursions, which gradually increase in frequency and duration, whilst continuing to suckle from the mother. Eventually, juveniles accompany the mother on night time foraging trips, and by the end of March, they range free from their mother (7). Monito del montes become sexually mature in their second year (2).
In the harsh environment in which they live, the monito del monte requires a number of adaptations to the cold. Its dense fur and small, well-furred ears prevent heat loss (2) (3), and they sleep in nests constructed under the shelter of overhanging rocks, fallen tree trunks or amongst the roots of trees. The nests are constructed from water repellent leaves and are often covered with protective and warm moss. During winter when temperatures drop further and food is scarce, the monito del monte enters hibernation. Before hibernation, the base of the tail swells with an accumulation of fat, and the heart rate drops from 230 beats per minute to less than 30 per minute (2).