Lion-tailed macaques may raid agricultural fields and orchards and are sometimes shot as pests (Burton, 1995).
Negative Impacts: crop pest
It is likely that these animals fall prey to snakes, raptors, and larger carnivores.
Lion-tailed macaques are 40 to 61 cm in length, with the tail adding an additional 24 to 38 cm. Males typically weigh between 5 and 10 kg, but the smaller females weigh only 3 to 6 kg.
The body is covered with black fur. The tail is long, thin, and naked, with a tuft of black puffy hair at the tip. Both males and females have a grayish lion-like mane of fur that surrounds the face. The face itself is bare and black.
Macaca silenus has two incisors, one canine, three premolars, and two molars in each quadrant of the mouth (Lawlor, 1979). Lion-tailed macaques have cheek pouches that open beside the lower teeth and extend down the side of the neck.
Offspring are born with soft, black pelage that is replaced with adult pelage after two months of age (Burton, 1995).
Range mass: 3 to 10 kg.
Range length: 40 to 61 cm.
Other Physical Features: endothermic ; homoiothermic; bilateral symmetry
Sexual Dimorphism: male larger
Macaca silenus has a maximum lifespan of 38 years in captivity, although it is more typical for them to reach about 30 years of age. In the wild, the expected maximum lifespan is about 20 years.
Average lifespan
Status: wild: 20 years.
Range lifespan
Status: captivity: 38 (high) years.
Average lifespan
Status: captivity: 30 years.
Average lifespan
Sex: female
Status: captivity: 40.0 years.
Average lifespan
Sex: male
Status: captivity: 38.0 years.
Average lifespan
Status: wild: 30.0 years.
Macaca silenus lives in evergreen and semi-evergreen rainforests and monsoon forests. They typically are associated with broadleaf trees, and can be found at elevations as great as 1,500 m.
Range elevation: 1,500 (high) m.
Habitat Regions: tropical ; terrestrial
Terrestrial Biomes: rainforest ; mountains
Lion-tailed macaques (Macaca silenus) are found only in India in the Western Ghats mountains.
Biogeographic Regions: oriental (Native )
Lion-tailed macaques are omnivorous but their diet consists mainly of fruit. They also eat a wide variety of vegetation such as leaves, stems, flowers, buds, and fungi. They occasionally eat meat from insects, lizards, tree frogs, and small mammals. These macaques obtain some of their water by licking dew from leaves. Lion-tailed macaques prefer to forage quickly for fear of predators. Their cheeck pouches enable them to quickly gather large amounts of food in times of danger. "When fully extended, their cheek pouches can store an equilivant to their stomach's capacity" (Burton, 1995). Macaca silenus feed from dawn till dusk, generally, on foods that are closest to their sleeping ground (Nowak, 1999).
Animal Foods: mammals; amphibians; reptiles; insects
Plant Foods: leaves; wood, bark, or stems; fruit; flowers
Other Foods: fungus
Primary Diet: omnivore
Because of their frugivory and their ability to carry fruits in their large cheek pouches, it is likely that these monkeys play some role in seed dispersal. To the extent that they prey upon other animals, they may have some impact on prey populations. As prey animals themselves, lion-tailed macaques may have a positive impact on populations of their predators.
Ecosystem Impact: disperses seeds
Macaca silenus is hunted for its skin and meat. These animals are also used in the pet trade and for medical research (Burton, 1995).
Positive Impacts: pet trade ; food ; body parts are source of valuable material; research and education
Lion-tailed macaques are affected by habitat loss due to the harvesting of firewood, timber, and other forest products for human use (Burton, 1995). They are also subject to inbreeding, resulting from having low numbers in the wild and different troops being separated in small forest fragments.
In the 1980s, efforts were made to increase the population. Macaca silenus was put on the Species Survival Plan. Because lion-tailed macaques breed well in captivity, there are now 500 lion-tailed macaques in zoos worldwide and the population can be increased dramatically (Burton, 1995).
US Federal List: endangered; no special status
CITES: appendix i
IUCN Red List of Threatened Species: endangered
Macaques have extensive patterns of communication, typical of diurnal primates. They rely heavily on vocal communication. "Lion-tailed macaques have 17 different vocal patterns and many types of body movements used to express communication" (Burton, 1995). In addition, visual communication (through body postures and facial expression), and tactile communication (in the form of grooming, play, mounting, and aggression) occur in macaques. It is likely that some chemical communication occurs, especially as pertains to advertizement of oestrus (Nowak, 1999).
Communication Channels: visual ; tactile ; acoustic ; chemical
Perception Channels: visual ; tactile ; acoustic ; chemical
This species is polygynous. Groups of M. silenus typically contain one male and several females and juveniles.
Mating System: polygynous
In lion-tailed macaques, females become sexually mature at 5 years of age, and males mature at 8 (Nowak, 1999). Macaca silenus has no specific breeding season. When a female is in estrus, swelling occurs in the area under her tail (perineal oestrus swelling) and she emits a courtship call to let males know she is ready to copulate (Nowak, 1999). Courtship generally consists of the male examining the female's genitals and then isolation of the couple from the troop in order to copulate without interruption. Once they have copulated, the two do not stay together.
After gestation period of approximately 6 months, females typically give birth to one offspring (Burton, 1995). Although breeding occurs throughout the year, most births coincide with the peak of the wet season when resources are abundant. Newborn macaques weigh betweem 400 and 500 g (Nowak, 1999). Females tend to carry the offspring on their abdomens. Males and females reach maturity at different ages, with males maturing later, at 8 years of age. Females can produce their first offspring around the age of 5 years (Nowak, 1999).
In most macaques, females can reproduce once per year if conditions are good. Young are weaned before they reach one year of age.
Breeding interval: Females can probably reproduce about once per year if conditions are favorable.
Breeding season: Macaca silenus has no specific breeding season.
Average number of offspring: 1.
Average gestation period: 180 days.
Average time to independence: 4 years.
Average age at sexual or reproductive maturity (female): 5 years.
Average age at sexual or reproductive maturity (male): 8 years.
Key Reproductive Features: iteroparous ; year-round breeding ; gonochoric/gonochoristic/dioecious (sexes separate); sexual ; fertilization ; viviparous
Average birth mass: 407 g.
Average gestation period: 176 days.
Average number of offspring: 1.
Average age at sexual or reproductive maturity (male)
Sex: male: 2511 days.
Average age at sexual or reproductive maturity (female)
Sex: female: 1429 days.
Females nurse and care for their young for extended periods while the young learn and grow. When offspring reach adolescence, females generally stay in the social group of their birth, but males leave, and live in nomadic all-male groups until they are able to defend a harem of their own. Males may establish a new family group or steal one from an old or injured male of another group.
Parental Investment: altricial ; pre-fertilization (Provisioning, Protecting: Female); pre-hatching/birth (Provisioning: Female, Protecting: Female); pre-weaning/fledging (Provisioning: Female, Protecting: Female); pre-independence (Provisioning: Female, Protecting: Female); post-independence association with parents; extended period of juvenile learning; inherits maternal/paternal territory
The lion-tailed macaque (Macaca silenus), also known as the wanderoo, is an Old World monkey endemic to the Western Ghats of South India.
Lion-tailed macaques are covered in black fur, and have a striking gray or silver mane that surrounds their face which can be found in both sexes. The face itself is hairless and black, being pinkish in infants less than a year old. They are named not for their mane, but for their tail, which is long, thin, and naked, with a lion-like, black tail tuft at the tip. The size of their tail is about 25 cm (9.8 in) in length. Their eyes are a shade of hazelnut with highlighting black eyelids. Lion-tailed macaques, like other macaques, have deep cheek pouches useful for storing food, and are quadrupedal with opposable digits. The mane that surrounds its face gives this monkey its German name Bartaffe – "beard ape". With a head-body length of 42–61 cm (17–24 in) and a weight of 2–10 kg (4.4–22.0 lb), it ranks among the smaller macaques species. Offspring are born with lighter faces and no mane, with the adult mane growing in after two months after birth.[4]
The lion-tailed macaque is a rainforest dweller, often being found in the upper canopy of tropical moist evergreen forests or monsoon forests. It is diurnal, meaning it is active exclusively in daylight hours. When they’re active, they will spend half the day foraging, and the other half will be spent resting or finding new areas to forage.[4] Unlike other macaques, it typically avoids humans when possible. In group behavior, the lion-tailed macaque is much like other macaques, living in hierarchical groups of usually 10 to 20 members, which usually consist of few males, typically 1-3, and many females. They have a polygynous mating system with no specific breeding season. While there is no specific breeding season, they do tend to breed in the wet season when resources are most abundant. [4] Little time is spent grooming or playing with others in the group. Of the few males, only one will be the dominant male, who will protect his troop from others and be the one who breeds. It is a territorial animal, defending its area first with loud cries and bared teeth towards the invading troops. If this proves to be fruitless, it brawls aggressively, which can result in severe injuries due to lacerations from their large canines. Other forms of communication come in the form of mounting to show strength, branch shaking to scare off, lip-smacking as a friendly greeting, or yawning with a grimace to indicate dominance.[4]
Lion-tailed macaque behavior is characterized by typical patterns of arboreal living. This patterns involve selectively feeding on a large variety of fruit trees, large interindividual spaces while foraging, and time budgets with high proportion of time devoted to exploration and feeding.[5] Lion-tailed macaques are omnivores, primarily eating indigenous fruits, seeds, flowers, insects, snails, and small vertebrates in virgin forest. Lion-tailed macaques are very important for seed dispersal, and are able to transport seeds long distances by either dropping or defecating seeds. However, due to changes in their environment, adaption to rapid environmental change has occurred in areas of massive selective logging through behavioral modifications and broadening of food choices. These changes involve a large increase in ground foraging and feeding on far more non-native plants and insects.[4] These feeding changes include fruits, seeds, shoots, pith, flowers, cones, mesocarp, and other parts of many non-indigenous and pioneer plants.[5] In the forests of Kerala they were observed preying on nestlings and eggs of pigeons.[6]
Gestation lasts approximately six months. The young are nursed for one year. Sexual maturity is reached at four years for females, and six years for males. The life expectancy in the wild is approximately 20 years, while in captivity is up to 30 years.[7]
While lion-tailed macaques are preyed on by snakes, raptors, and large carnivores, the impact of natural predators on population size doesn’t compare to their largest threat. The largest threat to the lion-tailed macaque is habitat fragmentation due to large amounts of timber harvesting and exotic plantations, such as tea and coffee.[2] This fragmentation leads to many issues that the lion-tailed macaques are facing. They are struggling to find food, being hit by cars, and being electrocuted by power lines.[4] Due to their low numbers and high levels of fragmentation, they are also highly susceptible to inbreeding, which can cause many genetic issues.[8] Their second largest threat is from humans hunting and trapping them for meat, especially within areas that have primates as their preferred food. There are also many human-primate conflicts occurring now due to macaques venturing out of their forests to find food.
An assessment in 2003 for IUCN reports 3000–3500 of these animals live scattered over several areas in Tamil Nadu, Kerala, Karnataka.[9] The lion-tailed macaque ranks among the rarest and most threatened primates. Their range has become increasingly isolated and fragmented by the spread of agriculture and tea, coffee, teak and cinchona, construction of water reservoirs for irrigation and power generation, and human settlements to support such activities. They do not live, feed or travel through plantations. Destruction of their habitat and their avoidance of human proximity have led to the drastic decrease of their population.
From 1977 to 1980, public concern about the endanged status of lion-tailed macaque became the focal point of Save Silent Valley, India's fiercest environmental debate of the decade. From 1993 to 1996, 14 troops were observed in Silent Valley National Park, Kerala, one of the most undisturbed viable habitats left for them.[10] Silent Valley has the largest number of lion-tailed macaques in South India. Other protected areas in Kerala include Neyyar Wildlife Sanctuary, Peppara Wildlife Sanctuary, Shendurney Wildlife Sanctuary, Periyar Tiger Reserve and its premises (Gavi and Konni), Eravikulam National Park, Pambadum Shola National Park, Parambikulam Tiger Reserve, Annaimalai Tiger Reserve, New Amarambalam Reserved Forest, Aralam Wildlife Sanctuary and Chimmony Wildlife Sanctuary and Wayanad region.
A self-sustainable single population of 32 groups of lion-tailed macaques occurred in Sirsi-Honnavara, Karnataka, the northernmost population of the species.[11] A local census concluded in 2007, conducted in the Theni District of Tamil Nadu, put their numbers at around 250, which was considered encouraging, because until then, no lion-tailed macaques had been reported in that specific area.[12] The species is also prominently found in the Papanasam part of the Kalakkad Mundanthurai Tiger Reserve of Tirunelveli district, the Palani Hills Wildlife Sanctuary and National Park of Dindigul, the Anaimalai Tiger Reserve of Coimbatore in Tamil Nadu. Many zoos take part in breeding programs which help to secure the survival of this species. About 338 of these macaques are reported to live in zoos.[7] (In July 2021 Australia's Rockhampton Zoo euthanased Australia's last lion-tailed macaque after its companion died of natural causes.[13]) However, it is no longer on ‘The World's 25 Most Endangered Primates’ list, after the international body compiling it determined that the local governments in southern India had acted positively to protect it.
The lion-tailed macaque (Macaca silenus), also known as the wanderoo, is an Old World monkey endemic to the Western Ghats of South India.
