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
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
Lion-tailed macaques may raid agricultural fields and orchards and are sometimes shot as pests (Burton, 1995).
Negative Impacts: crop pest
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
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
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
Lion-tailed macaques (Macaca silenus) are found only in India in the Western Ghats mountains.
Biogeographic Regions: oriental (Native )
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
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.
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
It is likely that these animals fall prey to snakes, raptors, and larger carnivores.
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
