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. (BBC, 2005; Nowak, 1999)
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.
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).
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. (Lawlor, 1979; Nowak, 1999)
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. (BBC, 2005; Nowak, 1999; BBC, 2005; Nowak, 1999)
Lion-tailed macaques are arboreal and diurnal. They travel in a family group consisting of 10 to 20 members, but there can be as many as 34 members (Nowak, 1999). Some groups may have as many as 3 adult males, but there is usually only one dominant male who is responsible for breeding (Nowak, 1999). Lion-tailed macaques are the only macaques in which males use calls to advertise their territorial boundaries (Nowak, 1999). Male macaques are territorial and generally give off a loud call to let entering troops know they are in the area. Two troups encounter one another, one usually moves away without any overt aggression. (Burton, 1995; Nowak, 1999)
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). (Burton, 1995; Nowak, 1999)
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). (Burton, 1995; Nowak, 1999)
It is likely that these animals fall prey to snakes, raptors, and larger carnivores.
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.
Lion-tailed macaques may raid agricultural fields and orchards and are sometimes shot as pests (Burton, 1995). (Burton, 1995)
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). (Burton, 1995; Burton, 1995)
Nancy Shefferly (editor), Animal Diversity Web.
Nicole Strawder (author), University of Michigan-Ann Arbor, Cynthia Sims Parr (editor), University of Michigan-Ann Arbor.
uses sound to communicate
young are born in a relatively underdeveloped state; they are unable to feed or care for themselves or locomote independently for a period of time after birth/hatching. In birds, naked and helpless after hatching.
Referring to an animal that lives in trees; tree-climbing.
having body symmetry such that the animal can be divided in one plane into two mirror-image halves. Animals with bilateral symmetry have dorsal and ventral sides, as well as anterior and posterior ends. Synapomorphy of the Bilateria.
uses smells or other chemicals to communicate
ranking system or pecking order among members of a long-term social group, where dominance status affects access to resources or mates
animals that use metabolically generated heat to regulate body temperature independently of ambient temperature. Endothermy is a synapomorphy of the Mammalia, although it may have arisen in a (now extinct) synapsid ancestor; the fossil record does not distinguish these possibilities. Convergent in birds.
union of egg and spermatozoan
A substance that provides both nutrients and energy to a living thing.
offspring are produced in more than one group (litters, clutches, etc.) and across multiple seasons (or other periods hospitable to reproduction). Iteroparous animals must, by definition, survive over multiple seasons (or periodic condition changes).
having the capacity to move from one place to another.
This terrestrial biome includes summits of high mountains, either without vegetation or covered by low, tundra-like vegetation.
the area in which the animal is naturally found, the region in which it is endemic.
an animal that mainly eats all kinds of things, including plants and animals
found in the oriental region of the world. In other words, India and southeast Asia.
the business of buying and selling animals for people to keep in their homes as pets.
having more than one female as a mate at one time
rainforests, both temperate and tropical, are dominated by trees often forming a closed canopy with little light reaching the ground. Epiphytes and climbing plants are also abundant. Precipitation is typically not limiting, but may be somewhat seasonal.
remains in the same area
reproduction that includes combining the genetic contribution of two individuals, a male and a female
associates with others of its species; forms social groups.
uses touch to communicate
Living on the ground.
defends an area within the home range, occupied by a single animals or group of animals of the same species and held through overt defense, display, or advertisement
the region of the earth that surrounds the equator, from 23.5 degrees north to 23.5 degrees south.
uses sight to communicate
reproduction in which fertilization and development take place within the female body and the developing embryo derives nourishment from the female.
breeding takes place throughout the year
BBC, 2005. "Lion-tailed Macaque, wanderoo" (On-line). Accessed May 31, 2005 at http://www.bbc.co.uk/nature/wildfacts/factfiles/220.shtml.
Burton, F. 1995. The Multimedia Guide to the Non-Human Primates. Ontario: Prentice Hall Canada.
Lawlor, T. 1979. Encyclopedia of Mammals. New York: McGraw-Publishing Company.
Nowak, R. 1999. Walker's Mammals of the World, Sixth Edition. Boston and London: The Johns Hopkins University Press.