|Scientific Name:||Aotus nigriceps|
|Species Authority:||Dollman, 1909|
|Taxonomic Notes:||It is doubtful that the current taxonomy provides a true picture of the diversity of the genus Aotus. Ruiz-Herrera et al. 2005) reported that cytogenetic studies have characterized 18 different karyotypes with diploid numbers ranging from 46 to 58 chromosomes. The taxonomy of the night monkeys essentially follows the revision by Hershkovitz (1983), with some modifications for the Colombian and Central American forms.|
|Red List Category & Criteria:||Least Concern ver 3.1|
|Assessor(s):||Cornejo, F. & Palacios, E.|
|Reviewer(s):||Mittermeier, R.A. & Rylands, A.B. (Primate Red List Authority)|
This species is listed as Least Concern due to its wide range, suspected large populations, and because there are no major threats believed to be resulting in a significant population decline at present. However, given ongoing development projects, the species does require close population monitoring.
|Range Description:||Aotus nigriceps occurs throughout a large part of the central and upper Amazon, south of the mainstream and along the right bank of the Rio Jutaí in the west. In the east, it extends to the rios Tapajós and Juruena (Aotus azarae infulatus occurs to the east of the rios Tapajós and Juruena). It occurs throughout the state of Rondônia in Brazil, restricted to east of the Rio Guaporé. In Bolivia, it occurs north of the Río Madre de Dios in the Department of Pando (Hershkovitz 1983; Brown and Rumiz 1986; Anderson 1997), extending to the south-eastern and central Peruvian Amazon, west through the Río Ucayali basin to the east (right bank) of the Rio Huallaga (A. miconax coccurs to the west) to about 7ºS (Aquino and Encarnación 1994a).|
Native:Bolivia, Plurinational States of; Brazil (Acre, Amazonas, Mato Grosso, Pará, Rondônia); Peru
|Range Map:||Click here to open the map viewer and explore range.|
|Population:||Wright (1981, 1985) estimated a density of 36-40 indviduals/km² at Cocha Cashu, Manu National Park. Aquino and Encarnación (1994b) reviewed population structure and densities for the genus.|
|Habitat and Ecology:||
Night monkeys typically occur in primary and secondary forest (including disturbed forest and selectively logged forest), seasonally flooded and terra firma, lowland forest (Aquino and Encarnación 1986a, 1988, 1994a,b; Defler 2004). Aquino and Encarnación (1994b) reviewed the habitat and forest preferences of the genus.
Night monkeys are nocturnal: they are most active at dawn and dusk. The only exception is Aotus azarae azarae of the Chaco of southern Bolivia, Paraguay and Argentina, which is cathemeral (active during night and day). They are frugivorous; their diet includes fruit, nectar and flower (seasonally important for the A. a. azarae in the Chaco), leaves, and small animals prey such as insects (Wright 1989; Fernandez-Duque 2007).
They are socially monogamous, living in small groups of an adult pair and offspring of different ages (infant, one or two juveniles and sometimes a subadult. In A. a. azarae, a significant number of adults range alone. They may be subadults that have left their natal groups or older adults which have been evicted from their groups by competitors (Fernandez-Duque and Huntington 2002; Fernandez-Duque 2004). Both sexes disperse. Males care for the infants (carry them) (Rotundo et al. 2002, 2005). Lone adults were observed by Villavicencio Galindo (2003) in northern Colombia. Night monkeys are territorial—groups occupy overlapping territories of 5-18 ha (depending on the species and location) (Wright 1978; Fernandez-Duque 2007). In Cocha Cashu, Manu National Park, Peru, Wright (1989) recorded home range size for A. nigriceps of 7 to 14 ha. Wright (1994) and Fernandez-Duque (2007) review the behaviour and ecology of the genus.
Captive male A. lemurinus reach sexual maturity when 2 years old, and captive female A. vociferans and A. nancymaae first breed when 3-4 years old (Dixson 1983; Fernandez-Duque 2007). In the wild, male A. azarae reach adult weight only when about 4 years old, and age at first reproduction is about 5 years of age (Juárez et al. 2003; Fernandez-Duque 2004). Single offspring are the rule. Wright (1985) recorded births between August and February for A. nigriceps in Peru (Manu National Park), and Aquino et al. (1990) indicated a birth season between December and March for A. nancymaae in north-eastern Peru.
Adult male weight 875 kg (n=1), adult female weight 1.04 kg (n=2) (Peres 1993a).
|Major Threat(s):||A wide ranging species of the upper Amazon, there are currently no major threats believed to be resulting in a significant population decline. However, populations have been depleted over large areas in the states of Acre and Rondônoia, and with infrastructure development along major development corridors ((Porto Velho - Cuiabá and Porto Velho- Manausm and the Rio Madeira itself), it is likely that large tracts of forest will be lost in the future.|
Confirmed, or may occur, in several protected areas, including:
Manuripe National Reserve (Brown and Rumiz 1986)
Amazonia National Park (1,114,917 ha) (in range)
Serra do Divisor National Park (846,408 ha)
Juruena National Park
Pacáas Novos National Park
Abufari Biological Reserve (224,819 ha)
Guaporé Biological Reserve (618,173 ha)
Rio Acre Ecological Station (79,418 ha)
Manu National Park (1,532,806 ha) (Wright 1978, 1985).
It is listed on Appendix II of CITES.
Anderson, S. 1997. Mammals of Bolivia: Taxonomy and distribution. Bulletin of the American Museum of Natural History 231: 1–652.
Aquino, R. and Encarnación, F. 1986. Population structure of Aotus nancymai (Cebidae: Primates) in Peruvian Amazon lowland forest. American Journal of Primatology 11: 1-7.
Aquino, R. and Encarnación, F. 1988. Population densities and goegraphic distribution of night monkeys (Aotus nancymai and Aotus vociferans) (Cebidae: Primates) in northeastern Peru. American Journal of Primatology 14: 375-381.
Aquino, R. and Encarnación, F. 1994. Owl monkey populations in Latin America: field work and conservation. In: J. F. Baer, R. E. Weller and I. Kakoma (eds), Aotus: The Owl Monkey, pp. 59-95. Academic Press, San Diego, CA, USA.
Aquino, R. and Encarnación, F. 1994. Primates of Peru / Los Primates del Perú. Primate Report 40: 1-127.
Aquino, R., Puertas, P. E. and Encarnación, F. 1990. Supplemental notes on population parameters of northeastern Perucvian night monkeys, genus Aotus (Cebidae). American Journal of Primatology 21: 215-221.
Brown, A. D. and Rumiz, D. I. 1986. Distribucion de los primates en Bolivia. In: M. T. de Mello (ed.), A Primatologia no Brasil, pp. 335-363. Sociedade Brasileira de Primatologia, Brasília, Brazil.
Defler, T. R. 2004. Primates of Colombia. Conservation International, Washington, DC, Usa.
Dixson, A. F. 1983. The owl monkey (Aotus trivirgatus). In: J. P. Hearn (ed.), Reproduction in New World Primates: new Models in Medical Sciences, pp. 69-113. International Medical Publishers, Lancaster, UK.
Fernandez-Duque, E. 2004. High levels of intrasexual competition in sexually monomorphic owl monkeys (Aotus azarai). Foliia Primatologica 75(1): 260.
Fernandez-Duque, E. 2007. Aotinae: Social monogamy in the only nocturnal haplorhines. In: C. J. Campbell, A. Fuentes, K. C. Mackinnon, M. Panger and S. K. Bearder (eds), Primates in Perspective, pp. 139-154. Oxford University Press, Oxford, UK.
Fernandez-Duque, E. and Huntington, C. 2002. Disappearances of individuals from social groups have imolications for understanding natal dispersal in monogamous owl monkeys (Aotus azarai). American Journal of Primatology 57: 219-225.
Hershkovitz, P. 1983. Two new species of night monkeys, genus Aotus (Cebidae, Platyrrhini): A preliminary report on Aotus taxonomy. American Journal of Primatology 4: 209–243.
Juárez, C., Rotundo, M. and Fernandez-Duque, E. 2003. Behavioral sex differences in the socially monogamous night monkeys of the Argentinean Chaco. Revista de Etologia 5: 174.
Peres, C. A. 1993. Notes on the primates of the Juruá River, western Brazilian Amazina. Folia Primatologica 61: 97-103.
Rotundo, M., Fernandez-Duque, E. and Dixson, A. F. 2005. Infant development and paretnal care in free-rannig groups of owl monkeys (Aotus azarai azarai) in Argentina. International Journal of Primatology 36(6): 1459-1473.
Rotundo, M., Fernandez-Duque, E. and Giménez, M. 2002. Cuidado biparental en el mono de noche (Aotus azarai azarai) de Formosa, Argentina. Neotropical Primates 10: 70-72.
Ruiz-Herrera, A., García, F., Aguilera, M., Garcia, M. and Fontanals, M. P. 2005. Comparative chromosome painting in Aotus reveals a highly derived evolution. American Journal of Primatology 65: 73–85.
Salazar-Bravo, J. A., Tarifa, T., Aguirre, L. F., Yensen, E. and Yates, T. L. 2003. Revised Checklist of Bolivian Mammals. Occasional Papers, Museum of Texas Tech University 220: 1-28.
Villavicencio Galindo, J. M. 2003. Distribución geográfica de los primates del género Aotus en el Departamento Norte de Santander, Colomiba. In: V. Pereira-Bengoa, F. Nassar-Montoya and A. Savage (eds), Primatología del Nuevo Mundo, pp. 264-271. Centro de Primatología Araguatos, Bogotá, Colombia.
Wright, P. C. 1978. Home range, activity pattern, and agonistic encounters of a group of night monkeys (Aotus trivrgatus) in Peru. Folia Primatologica 29: 43–55.
Wright, P. C. 1981. The night monkeys, genus Aotus. In: A. F. Coimbra-Filho and R. A. Mittermeier (eds), Ecology and Behavior of Neotropical Primates, Vol. 1, pp. 211-240. Academia Brasileira de Ciências, Rio de Janeiro, Brazil.
Wright, P. C. 1985. The costs and benefits of nocturnality for Aotus trivirgatus (the night monkey). Ph.D .Thesis, City University of New York.
Wright, P. C. 1989. The nocturnal primate niche in the New World. Journal of Human Evolution 18: 635-638.
Wright, P. C. 1994. The behavior and ecology of the owl monkey. In: J. F. Baer, R. E. Weller and I. Kakoma (eds), The Owl Monkey, pp. 97-112. Academic Press, San Diego, CA, USA.
|Citation:||Cornejo, F. & Palacios, E. 2008. Aotus nigriceps. The IUCN Red List of Threatened Species. Version 2015.2. <www.iucnredlist.org>. Downloaded on 30 June 2015.|