Monito del monte (Dromiciops gliroides)

Also known as: colocolo
Synonyms: Dromiciops australis
  
French: Opossum Austral
Spanish: Comadrejita Enana, Llacas
KingdomAnimalia
PhylumChordata
ClassMammalia
OrderMicorbiotheria
FamilyMicrobiotheriidae
GenusDromiciops (1)
SizeHead-body length: 83 – 130 mm (2)
Tail length: 90 – 132 mm (2)
Weight16.7 – 31.4 g (2)

Classified as Near Threatened (NT) on the IUCN Red List (1).

The monito del monte, or ‘monkey of the mountains’, is not a monkey, but a South American marsupial, which has often been called a ‘living fossil’ due to it being the only living member of an otherwise extinct order, the Microbiotheria (3). In appearance it looks similar to a large mouse, with silky, short, dense fur that is fawn-grey on the upperparts and dirty yellowish-white underneath. The pale grey face has distinct black rings around the eyes, and the crown and nape of the neck are shaded cinnamon. The ears of the monito del monte are short, rounded and covered with short hair, and its robust limbs relate to its slow, ponderous movements. The tail, which is thick at the base and tapers to a tip, is thickly furred with fawn-coloured fur at the base, turning to straighter dark brown fur towards the tip (2). Females are, on average, significantly longer and heavier than males (4), and like most other marsupials, females can also be distinguished by their distinct abdominal pouch with four mammae, in which the tiny young will develop and grow (2).

Occurs in south-central Chile, from Concepción south to Chiloé Island, and east to the mountains slightly beyond the Argentine border (2).

The monito del monte inhabits dense, cool, humid forests, where it favours thickets of Chilean bamboo (Chusquea species) (2).

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).

Over recent years, the monito del monte population has declined, probably due to the loss of its already limited habitat (1). The forests of south-central Chile face severe pressure from human activities and development. For many years, forests have been cut for timber and fuelwood, and since the 1970s, large swathes of forest have been cleared for pine and eucalyptus plantations. Urbanisation, in the form of tourism developments and the construction of highways and hydroelectric complexes, also impacts the natural habitat in this region (8). The presence of the introduced murine rat (Rattus norvegicus) in some areas is also worrying (9).

The monito del monte occurs in at least two protected areas, the Reserva Nacional Los Ruiles (9) and the Valdivian Coastal Range Reserve, Chile. The Valdivian Coastal Range Reserve was created in 2005 by The Nature Conservancy, WWF, Conservation International and local conservation organisations, and protects 12 percent of the rare temperate rainforest of the region (10) (8), offering important protection for the habitat of the monito del monte. In addition, scientists on the island of Chiloé are researching the ecology and natural history of this species (11); such information is required to inform future conservation actions, and will hopefully ensure the survival of this fascinating ‘living fossil’.

For further information on the monito del monte see:

 

This information is awaiting authentication by a species expert, and will be updated as soon as possible. If you are able to help please contact:
arkive@wildscreen.org.uk

  1. IUCN Red List (June, 2009)
    http://www.iucnredlist.org
  2. Marshall, L.G. (1978) Dromiciops australis. Mammalian Species, 99: 1 - 5.
  3. Macdonald, D.W. (2006) The Encyclopedia of Mammals. Oxford University Press, Oxford.
  4. Rodríguez-Cabal, M.A., Amico, G.C., Novaro, A.J. and Aizen, M.A. (2008) Population characteristics of Dromiciops gliroides (Philippi, 1893), an endemic marsupial of the temperate forest of Patagonia. Mammalian Biology, 73(1): 74 - 76.
  5. Nowak, R.M. (1999) Walker's Mammals of the World. Sixth edition. The Johns Hopkins University Press, Baltimore and London.
  6. Amico, G. and Aizen, M.A. (2000) Mistletoe seed dispersal by a marsupial. Nature, 408: 929 - 930.
  7. Muñoz-Pedreros, A., Lang, B.K., Bretos, M. and Meserve, P.L. (2005) Reproduction and development of Dromiciops gliroides (Marsupialia: Microbiotheriidae) in temperate rainforests of southern Chile. Gayana, 69(2): 225 - 233.
  8. Biodiversity Hotspots: Chilean Winter Rainfall-Valdivian Rainforests (March, 2008)
    http://www.biodiversityhotspots.org/xp/Hotspots/chilean_forests
  9. Lobos, G., Charrier, A., Carrasco, G. and Palma, R.E. (2005) Presence of Dromiciops gliroides (Microbiotheria: Microbiotheriidae) in the deciduous forests of central Chile. Mammalian Biology, 70(6): 376 - 380.
  10. The Nature Conservancy (March, 2008)
    http://www.nature.org/wherewework/southamerica/chile/features/
  11. The burke Museum of Natural History and Culture (March, 2008)
    http://www.washington.edu/burkemuseum/collections/mammalogy/research/monito.html