Formosan rock macaques ( (Kunts and Myers, 1969)) are found in the mountainous terrain of northeastern and southwestern Taiwan. They may once have been associated with the sea coast but have now been largely restricted to inland hills because of human activity (Kuntz and Myers, 1969).
Formosan rock macaques inhabit primarily mixed coniferous-hardwood temperate forest, as well as bamboo and grassland at elevations between 100 and 3600 m . They are also found in coastal areas. (Grzimek, 1988) (Grzimek, 1988)
- Range elevation
- 100 to 3600 m
- 328.08 to 11811.02 ft
Formosan rock macaques are quadrupedal (Fleagle, 1988). They use cheek pouches to carry food in while foraging. The pelage is dark gray to brown in color. Tail length varies from 26 to 46 cm and body lengh ranges from 36 to 45 cm. They typically weigh 5 to 12 kg, though some adult males can be over 18 kg. The hairs are soft, a dark gray color in winter and an olive drab in summer; abdominal skin is slightly blue (Grzimek, 1988). (Fleagle, 1988; Grzimek, 1988)
- Sexual Dimorphism
- male larger
- Range mass
- 5 to 18 kg
- 11.01 to 39.65 lb
- Range length
- 36 to 45 cm
- 14.17 to 17.72 in
Most macaques are polygynous. Given the sexual dimorphism in size seen in (Grzimek, 1988), it is reasonable to assume that this species is, also.
- Mating System
Formosan rock macaques give birth to a single offspring per pregnancy. During estrus the perineum of the female swells at the base of the tail and along the thighs.
Gestation period is about 165 days. Young weigh an average of 400 g at birth. The mating season occurs from November through January, with births occuring from April through June. The mating season coincides with the peak of fruit availability. Females 5 to 9 years old usually give birth every other year, older females give birth every year (Rowe, 1996).
In most macaques, nursing lasts for about one year. Young are typically independent after about two years, although may retain life-long associations with their mother. (Fleagle, 1988; Grzimek, 1988; Nowak, 1991; Rowe, 1996)
- Key Reproductive Features
- seasonal breeding
- gonochoric/gonochoristic/dioecious (sexes separate)
- Breeding interval
- Females 5 to 9 years old usually give birth every other year, older females give birth every year.
- Breeding season
- The mating season occurs from November through January.
- Average number of offspring
- Average gestation period
- 165 days
- Average weaning age
- 12 months
Most parental care is provided by the mother. She grooms, nurses, protects her infant until it becomes independent. In most macaques, the period of nursing is about a year. Young are typically independent by two years of age. However, females may have relationships with their female kin for the remainder of their lives. Females remain in their natal group with the onset of maturity, but males disperse shortly before adolescence. There is a hierarchical dominance system among group members based upon the matriline.
- Parental Investment
- post-independence association with parents
- extended period of juvenile learning
- inherits maternal/paternal territory
- maternal position in the dominance hierarchy affects status of young
Most species in the genus Macaca live to be about 30 years old in captivity. Lifespans in the wild are probably shorter. It is reasonable to assume that is like other members of the genus in this respect. (Nowak, 1991)
Formosan rock macaques are diurnal primates with a multimale-multifemale social system with group sizes averaging 45 individuals. However, because of the recent decline in numbers, group structure resembles that of a unimale system and group sizes range typically between 2 and 10 individuals. Troops have 2 to 8 males, with a ratio of 1.25 males to 1.5 females. Territories overlap partially. Males emigrate and are solitary or form bachelor troops. Small troops with only 1 male have been observed to have an influx of bachelor males during the breeding season.
This macaque species, with its rounded head and flat muzzle, is intermediate in size and appearance between rhesus monkeys and Java monkeys. Reports dating from the previous century mention that this animal traveled with great agility over virtually inaccessible rocks on the seacoast, and that it lived in part on crustaceans and mollusks. Currently this macaque species persists only in the central hill country of Taiwan.
Formosan rock macaques are ground dwellers, comfortable in terrain with few trees or none. They are not shy and sometimes visit the fields of Taiwanese villagers, where they dig sweet potatoes and peanuts. They are hunted for this reason, and as a source of meat. (Grzimek, 1988) (Grzimek, 1988)
Communication and Perception
Formosan rock macaques emit 'scream calls' when approached by a non-group members. Group members answer this call with a sound that sounds like "kyaw-kyaw".
A fear grimace is when the lips are retracted so that the teeth are shown and clenched (Estes, 1991). This display functions as an appeasement signal to reduce aggression in aggressive encounters (Estes, 1991).
Staring with an open mouth but with the teeth covered indicates aggression (Estes, 1991).
As in other macaques, it is likely that tactile communication (grooming, playing, fighting, mating) is also important. There may be some chemical communication in the form a pheromones. (Estes, 1991; Grzimek, 1988)
Formosan rock macaques consume a wide variety of foods, including fruits, leaves, berries, seeds, insects, animal prey, buds, young shoots, and small vertebrates. These macaques reportedly raid crops (Rowe, 1996).
- Primary Diet
- Animal Foods
- Plant Foods
- seeds, grains, and nuts
These animals may be important in local food webs, and in helping to disperse seeds.
- Ecosystem Impact
- disperses seeds
Economic Importance for Humans: Positive
Macaques are popular zoo animals because of their active lifestyle and adaptability. They are also useful in biological, medicinal, and psychological research because of their similarity to humans in physiology and disease susceptibility. These animals may also be hunted for food. (Nowak, 1991)
- Positive Impacts
- research and education
Economic Importance for Humans: Negative
Parasites that infectmay be transmitted to humans, this is particularly a problem in recent years as tourism increases in the regions they inhabit and contact with humans becomes more frequent. They also are known to raid crops.
- Negative Impacts
- carries human disease
- crop pest
Situated in a subtropical zone, Taiwan possesses a warm and moist climate and a large variety of plants and wild life. Of the world's approximately 4,500 species of mammals, Taiwan has 61. In order to protect these precious natural resources in the face of growing economic development the Taiwanese government has in recent years actively promoted concepts of, and measures for, environmental conservation which have become widely accepted by the general public. Taiwan actively participates in important international treaties and organizations such as the Convention on International Trade in Endangered Species (CITES) and the International Union for the Conservation of Nature (IUCN).
once occured throughout Taiwan, but is now restricted to remote highlands by human encroachment. Macaques are killed for food, medicinal preparations, and taken as pets and for research purposes. The primary threat to their populations is habitat destruction.
Nancy Shefferly (editor), Animal Diversity Web.
Crystal Chiu (author), West Windsor-Plainsboro High School, Joan Rasmussen (editor), West Windsor-Plainsboro High School.
uses sound to communicate
- bilateral symmetry
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
- active during the day, 2. lasting for one day.
- dominance hierarchies
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.
A substance that provides both nutrients and energy to a living thing.
forest biomes are dominated by trees, otherwise forest biomes can vary widely in amount of precipitation and seasonality.
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.
- native range
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.
having more than one female as a mate at one time
- seasonal breeding
breeding is confined to a particular season
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
that region of the Earth between 23.5 degrees North and 60 degrees North (between the Tropic of Cancer and the Arctic Circle) and between 23.5 degrees South and 60 degrees South (between the Tropic of Capricorn and the Antarctic Circle).
Living on the ground.
- tropical savanna and grassland
A terrestrial biome. Savannas are grasslands with scattered individual trees that do not form a closed canopy. Extensive savannas are found in parts of subtropical and tropical Africa and South America, and in Australia.
A grassland with scattered trees or scattered clumps of trees, a type of community intermediate between grassland and forest. See also Tropical savanna and grassland biome.
- temperate grassland
A terrestrial biome found in temperate latitudes (>23.5° N or S latitude). Vegetation is made up mostly of grasses, the height and species diversity of which depend largely on the amount of moisture available. Fire and grazing are important in the long-term maintenance of grasslands.
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.
"Formosan rock-monkey" (On-line). Accessed (Date Unknown) at http://www.gio.gov.tw/info/ecology/specific/monk_e.html.
Burton, F. 1995. "The Multimedia Guide to the Non-human Primates". Prentice-Hall Canada Inc..
Estes, R. 1991. "The Behavior Guide to African Mammals". University of Califormia Press..
Fleagle, J. 1988. "Primate Adaptation and Evolution". Academic Press..
Grzimek, B. 1988. Grzimek's Encyclopedia of Mammals. Volume 2. NY: McGraw-Hill.
Kunts, R., B. Myers. 1969. A check-list of parasites and commensals reported for the Taiwan macaque. Primates, 10: 71-80.
Nowak, R. 1991. Walker's Mammals of the World. Baltimore and London: The Johns Hopkins University Press.
Rowe, N. 1996. The Pictorial Guide to The Living Primates. Pogonias Press.