The Barbary macaque is a very peculiar primate: it is the only macaque living outside Asia, is considered to be the most primitive of the genus Macaca, and it is one of just a few primate species that lives in a snowy environment for a conspicuous part of the year. It is thus surprising that very few studies have been conducted on this species in the wild.
The Barbary macaque is currently listed as endangered (IUCN 2010. IUCN Red List of Threatened Species. Version 2010.1. www.iucnredlist.org. Downloaded on 20th September 2010). The total population size in the wild is estimated between approximately 10,000 and 15,000 individuals (von Segesser et al. 1999; Camperio Ciani et al. 2005; van Lavieren & Wich, 2009). Deforestation, overgrazing and human interference represent the main causes of the decline of this species (Mehlman 1989). The Barbary macaque is generally found in cedar-oak (Cedrus atlantica & Quercus ilex) and deciduous oak forests (Q. faginea & Q. afores), scrub, grassland and rocky ridges (Fooden 2007). It is currently distributed in small patches of forest in Morocco and Algeria. The largest population of Barbary macaque inhabits the Middle Atlas Mountains of Morocco (Camperio Ciani et al. 2005), where the field site is located. This forest is an endangered ecosystem containing many endemic and rare plant and animal species.
Barbary macaques experience dry, hot summers and wet, snowy winters. The elevation distribution of Barbary macaques is considered to lie between 400 and 2300m asl (Fooden 2007). The Barbary macaque has a highly diverse diet comprising leaves, seeds, fruit, fungi, plant and animal matter, sap and roots (Menard 2002). Male and female macaques show sexual dimorphism in relation to their body length (males: 550-600mm, females: 450mm) and weight (males: 15.3-17kg, females: 10.2-11kg) (Fa 1989). Furthermore, males have elongated canines which play an important role in dominance related behaviours. The maximum recorded lifespan is 22 years in captivity and gestation length is 164.7 days (Fooden 2007). Sexual maturity is reached at around 6 years of age in males and 5 years of age in females (Menard et al. 1985). The Barbary macaque is a seasonal breeder with mating occurring between October and January and births occurring between late March to June in wild populations. Females show significant perineal swelling in the mating season, which is considered to signal the timing of ovulation and is attractive to males (Dixson 1998).
Barbary macaques live in multimale-multifemale groups of 10 to 50 monkeys. Group size and composition can vary dramatically. The average group size is between 15 and 50 individuals and sex ratio ranges between 0.6 and 1.6 females per male (Menard 2002). The Barbary macaque is considered a relatively tolerant species, with a shallow hierarchy, high frequency of undecided conflicts and/or counter-aggression, low degree of kin-bias in grooming, and high frequency of reconciliation (Thierry 2007). Grooming is observed frequently both in same-sex and hetero-sexual pairs. Infants are often carried by adult males and used as a ‘buffer’ to mediate social interactions among males.
References
Dixson A.F. (1998). Primate sexuality: Comparative studies of the prosimians, monkeys, apes, and human beings. Oxford University Press, USA.
Fa J.E. (1989). The genus Macaca: A review of taxonomy and evolution. Mammal Review, 19(2): 45-81.
Fooden J. (2007). Systematic review of the Barbary macaque, Macaca sylvanus (Linnaeus, 1758). Fieldiana Zoology, 113: 1-60.
Mehlman P.T. (1989). Comparative density, demography, and ranging behavior of Barbary macaques (Macaca sylvanus) in marginal and prime conifer habitats. International Journal of Primatology, 10(4): 269-292.
Ménard N. (2002). Ecological plasticity of Barbary macaques (Macaca sylvanus). Evolutionary Anthropology, 11: 95-100.
Ménard N., Vallet D. & Gautier-Hion A. (1985). Démographie et reproduction de Macaca sylvanus dans différents habitats en Algérie. Folia Primatologica, 44: 65-81.
Thierry B. (2007). Unity in diversity: lessons from macaque societies. Evolutionary Anthropology, 16: 224-238.
van Lavieren E. & Wich S.A. (2009). Decline of the Barbary macaques Macaca sylvanus in the cedar forest of the Middle Atlas Mountains, Morocco. Oryx, 44: 133-138.
Von Segesser F., Ménard N., Gaci B. & Martin D. (1999). Genetic differentiation within and between isolated Algerian subpopulations of Barbary macaques (Macaca sylvanus): evidence from microsatellites. Molecular Ecology, 8: 433-442.