Toque Macaque, Macaca sinica
TOQUE MACAQUE
Macaca sinica
Geographic Distribution and Habitat
The toque macaque, known scientifically as macaca sinica, is a monkey endemic to Sri Lanka. The species is present in all altitudes up to 6,889 feet (2,100m) and primarily inhabits forest ecosystems.
Distribution depends on subspecies with the dry zone toque macaque, also known as the common toque macaque (macaca sinica sinica), residing in North and East Sri Lanka’s dry evergreen forests in close proximity to permanent bodies of water. The wet zone toque macaque, also called the pale-fronted or the dusty-coated toque macaque (macaca sinica aurifrons) is in the Southwest lowland and midland tropical forests and wet zone lowland forests. Lastly, the highland toque macaque, or the hill-zone, or mountain toque macaque (macaca sinica opisthomelas), takes up the central montane tropical rainforest and occupies just 62.14 square miles (100 square kilometers).
Toque macaques are known locally in Sri Lanka as rilewa or rilawa and will sometimes live in human settlements. They have been found to stay around temples, earning their nickname as the “temple monkey”.
Size, Weight, and Lifespan
Toque macaques are sexually dimorphic with males being larger and having bigger teeth than their female counterparts.
The toque macaque is the smallest of the macaque species, with males weighing anywhere between 9 to 18.74 pounds (4.1 to 8.4 kg) and females 5.1 to 9.47 pounds (2.3 to 4.3 kg). Male head and body length is 17.32 to 20.87 inches (44 to 53 cm) while females are 15.75 to 17.72 inches (40 to 45 cm). Toque macaques also have long tails that measure the total length or more of their bodies. Males’ tails are 20.08 to 24.41 inches (51 to 62 cm) long, and females’ tails are 18.11 to 22.44 inches (46 to 57 cm) long.
Toque macaques can live up to 30 years in the wild, and captive monkeys up to 35 years of age.
In the wild, while 30 years is possible, most toque macaques do not live to this age due to intergroup conflicts, disease, infant mortality, and lack of resources, just to name a few. Many individuals will die within their first year of life, and those who make it to adulthood are not guaranteed to live until 30.
Appearance
The toque macaque is generally yellow-brown or golden-brown on the tops of their bodies with pale colored undersides. Males and females have pink faces that get slightly redder in color as they age. Both sexes have black elvish ears, dark eyelid borders, and black lower lips. The long tail is black or dark gray on top with a pale color on the underside and almost double the length of their bodies. Toque macaques notably lack fur on their palms, ears, faces, and sex skin. Sex skin is usually red in color next to hard butt pads on their bottoms. Toque macaques also have very dexterous hands with opposable thumbs, which help them in acquiring food and jumping between trees. While foraging, they will use their cheek pouches, which can grow to the size of their faces, to store food.
The most prominent of their features, the “toque” (named after a slouchy brimless hat), is a tuft of dark and long crown hairs that sits atop their head. Similar to a very poorly cut and extremely short bowl cut, this tuft of hair distinguishes them physically from any other macaque species.
Within the toque macaque species, we also see some subspecies variation in their toques and coloration. The dry zone toque macaque (M. s. sinica) has a golden brown toque and chestnut colored coat with a white underbelly. The wet zone toque macaque (M. s. aurifrons) has strong yellow hairs on the toque towards the front of the face and darker brown on the backside. Their coat is a dusty yellowish brown color that darkens closer to the behind. Underbellies are white for this subspecies as well. Lastly, the highland toque macaque (M. s. opisthomelas) is the largest of the three subspecies but has shorter and stouter limbs. Their fur is golden brown with gray olive undertones, with undersides that are also white.
Diet
Toque macaques, like many other macaques, have a highly variable diet. Primarily, these monkeys enjoy fruits and are considered frugivorous. Their fruits of choice often include berries and figs, but they also round out their diet with young leaves, insects, and the occasional small vertebrae, including reptiles and birds. Their favorite foods include the golden shower flowers, Indian ash tree, and tamarind, among other fruiting and flowering plants.
Much of what they eat is dictated by resource availability. Toque macaques are extremely resourceful and dextrous, so they will raid human crops, dig through trash, and steal from humans when natural food sources are low or inconvenient.
Behavior and Lifestyle
Toque macaques spend the majority of their lives in the tree canopy. Called arboreal, they avoid the forest floor to protect themselves against their predators, the leopard and Indian rock python. While using the canopy to their advantage, toque macaques are also excellent swimmers and can hide in bodies of water to avoid danger.
They are also diurnal, which means active during the day. In the daytime, they will forage for food, hang out with their group of family and friends, and nap. Younger toque macaques spend a lot of time playing and interacting with their friends as well. They are very curious and will spend time splashing in water to play while the adults spend time foraging or looking for food. Lower-ranking monkeys spend more time foraging in places with poorer resource quality, getting the short end of the stick compared to their higher-ranking groupmates.
Sleeping usually occurs in the trees, but at different locations each night to avoid predators. Sometimes they will form small huddles for extra protection.
While toque macaques frequently antagonize humans during their raids for food, they live alongside many other species of monkey in the wild. Since they fulfill different ecological niches, meaning they don’t eat the same food or require the same things to survive, they can live alongside northern plains gray langurs (Semnopithecus entellus) and purple-faced langurs (Trachypithecus vetulus).
The toque macaque is called “rilewa” or “rilawa” in Sri Lanka.
At the Nature Sanctuary and Archeological Reserve at Polonnaruwa, toque macaques have been studied in a free-ranging environment continuously for over five decades.
Toque macaques are named after their “toque”, or the whirl of fur on their head.
Toque macaques are excellent swimmers and can sometimes hide underwater from predators.
Toque macaques live in multi-male and multi-female groups of an average of 20 individuals, with groups reaching up to 40 individuals. Their social structure closely resembles the lion-tailed macaque (M. silenus), the bonnet macaque (M. radiata), the stump-tailed macaque (M. arctoides), and the barbary macaque (M. sylvanus) due to their more peaceful social organization compared to their more despotic macaque relatives like the rhesus (M. mulatta) or Japanese macaque (M. fusacata).
They operate more on conciliatory behaviors: grooming is not only reserved for relatives, and females will groom unrelated females. Communication that is common across macaque species is also understood as less aggressive in the toque macaques. For instance, teeth-baring, typically a submissive/aggressive fear response, is taken more as a friendly submissive response.
However, like other macaque species, males are more aggressive than females, and an alpha male will flex their ranking, taking food and bullying males below him. While they may be somewhat kinder to each other, they still have a strict social hierarchy to maintain. Their groups, also known as troops, have a hierarchy that starts with the alpha male and his group, followed by the alpha female and her group, other adult males, juvenile males, other adult females, and juvenile females. Infants, regardless of sex, are ranked based on the mother they are born to, with younger sisters outranking their older sisters. The female rank is determined by matriline. While alpha males come into power through prowess, females are born into their rank.
This rank is most obvious when food is available. Once food is found, the alpha male and his group are first to eat. The adult female group comes in next with the highest ranking female eating first. Once the top monkeys get their fill, the food is available to the rest of the ranks.
Like other macaques, toque macaque females are philopatric, meaning they stay in the group they were born into. Males will leave at sexual maturity and join another group. When joining, they may rise in rank enough to overthrow the current male or even cause enough disruptions for the group to break. Group fission is very common and allows for lower-ranking females to get better access to food and receive less harassment from both adult males and higher-ranking females during this period of rank instability.
Similar to other macaque species, toque macaques have a sophisticated call system. They use vocalizations to warn others of predators, to indicate stress, respond to social situations, or to notify those around them of food. Vocalizations can be categorized as alarm calls, submissive vocalizations, food calls, and aggressive vocalizations. The calls can sound like screams or screeches, indicating stress or alarm, to coos, indicating submission or food. Many calls will also be vocalized during play as well.
Aside from vocalizations, facial expressions are very important for communication. The toque macaque will fear-grimace, with their lips pulled back to reveal a scary teeth-forward smile. This can indicate high stress situations with other monkeys and can be a signal of submission or fear. Another common face is the aggressive open-mouth stare. Monkeys will make direct eye contact and open their mouths, oftentimes without even showing teeth. This is considered highly aggressive as eye contact is not initiated unless someone wants a fight.
Body language is also important. Branch shaking, ground slapping, and lunges are all signs of aggression. These, accompanied by open-mouth stares, are often the hallmark of a high-ranking monkey flexing rank. The poor lower-ranking monkey on the other side of this interaction would normally respond with a fear grimace.
Toque macaques are polyandrous, meaning a female will mate with multiple males. Males reach sexual maturity at 5-7 years of age, while females become sexually mature at 4-6 years old. This is the age at which they are able to bear children. While males initiate mating, females invite copulation. During the 28-day menstrual cycle, females will enter estrus for a couple of days. During this time, females are most fertile and their bodies will show it. Female genitalia, specifically the perineum, swells and turns bright red while the vagina secretes a pungent mucus signaling to males that they are fertile.
Gestation (pregnancy) takes 168 days, and a baby is typically born at night in the canopy or on the ground during the early morning hours. The birthing mother often separates herself from the group for the birth and uses her hands to assist in delivery. Lactation begins almost immediately, and the mother will resume foraging just 20 minutes after birth. The birthing mother, the highest-ranking female, and other females of the group will consume the placenta after the baby is born. This practice is called placentophagy.
The birthing season lasts from December to May and peaks in March. Once a baby is born, they will hold on to their mother for two months to learn critical social skills for development. Nursing lasts up to a year. While the birth mother provides primary care, other females of the group will also help take care of related siblings or even unrelated babies. This is called alloparenting.
Males do not participate in raising the child due to paternity uncertainty. Since females mate with many males, males do not know which baby is theirs. Investing energy, food, and time in a baby that might not be theirs is a huge risk. However, males will break up fights between juveniles in an effort to keep young monkeys safe. That does not deter them from bullying juveniles into their place in the hierarchy.
As frugivores, toque macaques are super powerful seed dispersers. Once a fruit is consumed, its seeds are expelled through feces and can take root, helping sustain the ecosystem they live in.
The International Union for Conservation of Nature lists the toque macaque as Endangered (IUCN, 2015), appearing on the IUCN Red List of Threatened Species.
The largest threat to these monkeys is habitat destruction. Within the last 50 years, more than 50% of the forest cover in Sri Lanka has been lost due to agriculture, namely tea plantations and logging, with increasing numbers each year. With the loss of habitats comes the devastating loss of monkey populations. For instance, the highland toque macaque subspecies has been reduced by more than 80% over the last 20 years due to agricultural development in their natural habitat. Additionally, these natural forested environments are critical for their survival since they are not tolerated in human-populated areas. Many toque macaque groups come close to human settlements and will raid crops, sift through trash, or steal food. These monkeys are commonly shot or trapped by farmers.
Toque macaques are listed in Appendix II of the Convention on International Trade in Endangered Species (CITES), an international agreement between governments whose goal is to ensure that international trade in specimens of wild animals and plants does not threaten their survival. While some individuals may live in protected areas, since they are considered pests, Sri Lanka has no official protection laws for the toque macaque.
- Gbif.org toque macaques
- IUCN Red List toque macaque
- dilmahconservation.org
- Smithsonian Interview Dr. Dittus (primates.lk)
- nathab.com Sri Lanka’s Ancient City of Polonnaruwa
- How Hierarchy Decides Everything in Toque Macaque Society youtube.com
- Mammals of Sri Lanka. Colombo: Field Ornithology Group of Sri Lanka. p. 1012. ISBN 978-955-8576-32-8.
Written by Nami Kaneko, May 2025