MOOR MACAQUE

Macaca maura

Geographic Distribution and Habitat

The Moor macaque (Macaca maura) is one of seven species of macaque found on the Indonesian island of Sulawesi. They are only found on the southwestern peninsula of the island at elevations below 6,600 feet (2,000 m), and overlap in some places with the Tonkean macaque. They inhabit rainforests and deciduous forests in the northern part of their range, but in the south inhabit both grasslands and mosaics of forests. They are also found on karst islands, a rocky habitat with underground cave systems. Sadly, much of their range has been disturbed by human activity and only small, isolated areas of high-quality forest habitat remain.

Moor macaque range, IUCN 2022

Size, Weight, and Lifespan

Moor macaques show significant sexual dimorphism in their body size. Males have a head and body length in the range of 25.2–27.2 inches (64–69 cm), whereas females are approximately 19.7–22 inches (50–56 cm) in length. Males weigh on average 13.9–21.6 pounds (6.3–9.8 kg) and females weigh on average 10.6–13.7 pounds (4.8–6.2 kg). They have very short tails, at around 1.8 inches (4.5 cm) for males and 1.2 inches (3 cm) for females.

Lifespan is thought to be around 28 years in this species.

Appearance

Moor macaques are large-bodied primates with very short tails. They are not a particularly colorful species of primate; most of their pelage ranges from a light brown to a dark brown, although the hair framing the face is a lighter shade of yellowish-gray. They have dark faces, hands, and ears. Their ischial callosities, thickened layers of tissue over their buttocks, are pale pink. At certain stages of their menstrual cycle, females will exhibit large sexual swellings.

Diet

While they do eat insects, as well as other plant matter, Moor macaques are predominantly frugivorous (fruit-eating). Figs in particular are a preferred food and make up a large part of their diet. They also feed on a wide variety of crops cultivated by humans, including bananas, corn, coconuts, and soybeans, among others, which can lead to human-macaque conflicts.

Behavior and Lifestyle

Moor macaques are semi-terrestrial; they spend time during the day both in the trees and on the ground. Most of the time they spend in trees during the day is spent foraging, whereas they spend most of their time on the ground traveling in a quadrupedal fashion (on all four limbs). They are diurnal and sleep in trees at night.

Individuals vary in their daily activity budgets, but in general around 30% of their time is spent foraging and 30% is spent resting. Social activities, such as grooming and playing, as well as resting makes up the rest of their days. When moving or resting, individuals tend to stay close to their matrilineal relatives.

The home range size of each group is around 50–75 acres (20–30 hectares), although this becomes smaller in the months when food is more abundant and they have to travel less to find it. They sometimes have encounters with neighboring groups, but these don’t tend to involve much direct contact.

Fun Facts

When in estrus, females will show a preference for the dominant male of the group, presenting to him more often than to lower-ranking males.

Moor macaques seem to be a relatively tolerant species of macaque, showing low levels of aggression between group members and high levels of reconciliation after conflicts. 

Folklore from southern Sulawesi says that the ancestors of humans became monkeys; humans in this area avoid entering the Moor macaque’s forest habitat to avoid disturbing them. This has probably helped the survival of this area of forest and its resident macaques. 

Daily Life and Group Dynamics 

Moor macaques live in multi-male, multi-female groups. They show female philopatry; females remain in their natal group, while males disperse from their natal group at around 7–9 years of age. The average group size tends to be around 20 individuals but can range in size from 15 to 43 individuals. 

In general, Moor macaques are a fairly tolerant species. The females exhibit a linear hierarchy, but there seems to be a fairly low level of severe aggression between females (in contrast to some other macaque species). Additionally, females often engage in affiliative behaviors after a conflict, which allows them to reconcile and maintain social bonds.

Males within a group do not interact very frequently but seem to have relatively tolerant relationships; when they do interact, these interactions are more often affiliative than aggressive in nature.

Communication

Moor macaques have a large repertoire of vocalizations that they use to communicate, including barks, grunts, screams, and coos, which are used across a wide variety of contexts.

Additionally, they use a large number of facial expressions, body postures, and tactile behaviors to communicate. One facial expression is the “silent bared-teeth display.” In some other species of macaque this is generally used by subordinates as a submissive signal; however, in the macaque species that inhabit the island of Sulawesi it is used by both high- and low-ranking individuals. In Moor macaques it is used in affinitive and playful behaviors and is thought to signal peaceful intentions and promote affiliative interactions.

Moor macaques also use a number of other gestures and signals to communicate across a variety of contexts, such as lip smacking to signal submission or affiliation, presenting their hindquarters to initiate copulation, or mounting to assert dominance over another individual.

Reproduction and Family

Once they reach sexual maturity at around 4–5 years of age, female Moor macaques begin to exhibit sexual swellings—this is a swelling of the perineum, which signals the female’s estrus state. On average this lasts around 12 days, although there is a lot of variation between, and indeed, within, individuals. When in estrus, females will approach males and present their hindquarters to them, which is often followed by the male mounting. Females seem to show a preference to present to the dominant male, and indeed subordinate males seem to copulate with females less often than the dominant male.

Females generally give birth to their first infant around the ages of 6–7 years. After a gestation period of approximately 180 days (6 months), they bear a single infant. On average, females give birth once every two years, although if their infant dies then they may give birth again sooner. When a female is holding her infant, other females in the group will show increased interest towards her, will groom her more often, and stay in closer proximity.

Ecological Role

Moor macaques are primarily frugivorous, and therefore likely play an important role in seed dispersal. This is likely to be true in particular for figs, which make up a large part of their diet.

Conservation Status and Threats

The Moor macaque is currently classified as Endangered by the International Union for Conservation of Nature (IUCN, 2015) and the overall population is thought to be decreasing. Some of its habitat falls within protected areas, but this is only a small area of the total distribution of this species.

The population of this species is now extremely fragmented, and it is increasingly restricted to karst areas, which are also under increasing threat due to cement mining and infrastructural development.

Major threats to this species include habitat disturbance and fragmentation caused by human development, increasing cement mining of karst areas, and the primate pet trade.

Moor macaques are also threatened by human-wildlife conflict, due to their crop-feeding behaviors. However, in some areas, people are tolerant of the macaques, despite damage to crops, owing to the importance of monkeys in local folklore.

Conservation Efforts

The Moor macaque is listed on Appendix II of the Convention on International Trade in Endangered Species (CITES) and so trade in this species is subject to regulation. However, more conservation actions are needed to protect this species, including protection of their karst habitats from mining, further habitat protection, and awareness campaigns to limit the primate pet trade.

References:
  • ​Matsumura, S. (1996). Postconflict affiliative contacts between former opponents among wild moor macaques (Macaca maurus). American Journal of primatology, 38(3), 211-219.
  • Matsumura, S. (1998). Relaxed dominance relations among female moor macaques (Macaca maurus) in their natural habitat, South Sulawesi, Indonesia. Folia Primatologica, 69(6), 346-356.
  • Matsumura, S. (1996). Postconflict affiliative contacts between former opponents among wild moor macaques (Macaca maurus). American Journal of primatology, 38(3), 211-219.
  • Matsumura, S., & Okamoto, K. (1997). Factors affecting proximity among members of a wild group of moor macaques during feeding, moving, and International Journal of Primatology18(6), 929-940.
  • Matsumura, S. (1997). Mothers in a wild group of moor macaques (Macaca maurus) are more attractive to other group members when holding their infants. Folia Primatologica68(2), 77-85.
  • Matsumura, S. (1993). Female reproductive cycles and the sexual behavior of moor macaques (Macaca maurus) in their natural habitat, South Sulawesi, Indonesia. Primates, 34(1), 99-103.
  • Okamoto, K., Matsumura, S., & Watanabe, K. (2000). Life history and demography of wild moor macaques (Macaca maurus): summary of ten years of observations. American Journal of Primatology: Official Journal of the American Society of Primatologists52(1), 1-11.
  • Okamoto, K., & Matsumura, S. (2001). Group fission in moor macaques (Macaca maurus). International Journal of Primatology22(3), 481-493.
  • Okamoto, K., & Matsumura, S. (2002). Intergroup encounters in wild moor macaques (Macaca maurus). Primates43(2), 119-125.
  • Riley, E. P., & Priston, N. E. (2010). Macaques in farms and folklore: exploring the human–nonhuman primate interface in Sulawesi, Indonesia. American Journal of Primatology, 72(10), 848-854.
  • Riley, E. P., Sagnotti, C., Carosi, M., & Oka, N. P. (2014). Socially tolerant relationships among wild male moor macaques (Macaca maura). Behaviour151(7), 1021-1044.
  • Sagnotti, C. (2013). Diet preference and habitat use in relation to reproductive states in females of a wild group of Macaca maura inhabiting Karaenta forest in South Sulawesi. Unpublished master’s thesis). Hasanuddin University, Makassar, South Sulawesi, Indonesia.
  • Zak, A. A., & Riley, E. P. (2017). Comparing the use of camera traps and farmer reports to study crop feeding behavior of moor macaques (Macaca maura). International Journal of Primatology, 38(2), 224-242.
  • Alltheworldsprimates.org
  • https://www.iucnredlist.org/species/12553/3356200

Written by Jennifer Botting, PhD, March 2020