Andean night monkey (Aotus miconax)
|Also known as:||Peruvian night monkey|
|Synonyms:||Aotus trivirgatus miconax|
|Size||Average weight: 1 kg (2)|
Classified as Vulnerable (VU) on the IUCN Red List (1) and listed on Appendix II of CITES (3).
With their small, rounded head and large eyes, giving a rather owl-like appearance, the night monkeys are an unmistakable group of primates. Adapted to a nocturnal lifestyle, the eyeballs are enlarged, but unlike many other nocturnal mammals the eyes lack the reflective ‘tapetum’, a unique character that indicates a recent evolutionary split from diurnal monkeys (4). The Andean night monkey has dense dark greyish fur, with lighter underparts and reddish patches on the side of the neck (5). The head is a greyish-white colour, with a conspicuous black patch on the forehead that stretches down the nose and around the eyes (4). Only slightly shorter than the body, the long tail acts to balance the monkey, while the long, narrow digits have claw-like nails and extensive padding that help to grip onto branches while traversing the canopy (6) (7).
Endemic to the Peruvian Andes, the Andean night monkey is found from the southeast of the Maranon River south towards the west bank of the Huallaga River, from 800 to 2,800 metres above sea level (1) (8).
Although most common in primary cloud forest, the Andean night monkey is also found in secondary forest and logged forest, occasionally close to human settlements (1) (8).
Owing to a paucity of species-specific studies, very little is known about the biology of the Andean night monkey. However, night monkeys are typically arboreal nocturnal forest dwellers that are most active on moonlit nights, and sleep under tangles of vines or in tree hollows during the day. By foraging at night these monkeys are able to avoid competition with diurnal monkeys for food and predation from birds of prey. A small, agile monkey, the Andean night monkey is adept at running on branches and, despite its comparatively small size, is capable of spectacular leaps of several metres (5). It is a largely frugivorous species, but will also eat leaves, bark, flowers and will catch large insects out of the air (4).
The basic group of the Andean night monkey is a breeding pair and their offspring, which defend a small territory (4). Night monkeys produce a remarkable variety of calls, inflating a sac under the chin to create a resonance in the voice, and use a number of trills and screams to communicate (5). Olfactory communication is also extremely important, with mature monkeys attracting mates by urinating on the hands and rubbing them on branches (2). Pairs are monogamous and will mate annually, producing a single young after a gestation period of some 133 to 141 days. Although the mother suckles the infant, the father is largely responsible for its upbringing, defending, playing with and instructing the young. The juveniles stay with the parents for two to four years, after which time they become temporarily nomadic as they search for a mate (5).
Being small in size and possessing a pungent scent gland, the Andean night monkey has escaped the intensive human hunting pressure that plights so many other New World primates. The historical remoteness of its habitat has also provided it sanctuary from other destructive human activities. However, the recent construction of a highway, and resulting urbanisation, has resulted in the acceleration of logging within much of its range. Consequently, loss of habitat has been responsible for the extirpation of the Andean night monkey from certain areas. Also, when people cut down trees to make way for the planting of crops, monkeys may be captured and subsequently kept as pets in local villages (1) (8).
Despite being found in a few protected areas, including Abiseo National Park, Cordillera de Colán and Bosque de Proteccion Alto Mayo, the population of the Andean night monkey is believed to have decreased in recent years. Fortunately the Andean night monkey is still abundant in the more remote parts of its range, and efforts to protect its habitat will hopefully ensure the survival of this curious little primate (1).
For more information on the conservation of the Andes, see:
For more information on conservation in Peru, see:
The Wildlife Conservation Society:
The Nature Conservancy:
Authenticated (20/05/10) by Matthew Richardson, primatologist and author.
- Arboreal: an animal which lives or spends a large amount of time in trees.
- Cloud forest: a tropical mountain forest, with a high incidence of cloud cover throughout the year.
- Diurnal: active during the day.
- Endemic: a species or taxonomic group that is only found in one particular country or geographic area.
- Frugivorous: fruit eating/ fruit eater.
- Gestation: the state of being pregnant; the period from conception to birth.
- Monogamous: having only one mate during a breeding season, or throughout the breeding life of a pair.
- Nocturnal: active at night.
- Primary forest: forest that has remained undisturbed for a long time and has reached a mature condition.
- Secondary forest: forest that has re-grown after a major disturbance, such as fire or timber harvest, but has not yet reached the mature state of primary forest.
IUCN Red List (March, 2010)
The Primata (March, 2010)
CITES (March, 2010)
Primate Info Net (March, 2010)
- Nowak, R.M. (1999) Mammals of the World. The John Hopkins University Press, Baltimore.
- Eisenberg, J.F. and Redford, K.H. (2000) Mammals of the Neotropics. Volume 3. The Central Neotropics: Ecuador, Peru, Bolivia, Brazil. University of Chicago Press, Chicago.
- Fleagle, J.G. (1999) Primate Adaptation and Evolution. Second Edition. Academic Press, New York.
- Cornejo, F.M., Aquino, R. and Jimenez, C. (2008) Notes on the natural history, distribution and conservation status of the Andean night monkey, Aotus miconomax Thomas 1927. Primate Conservation, 23: 1-4.