Life span: 25 years
Total population: Unknown
Regions: China, India, Bhutan, Laos, Burma, Nepal, Bangladesh, Thailand, Vietnam, Pakistan, Afghanistan
Gestation: 5.5 months (164 days)
Height: 531.8 mm (M), 468.8 mm (F)
Weight: 7.7 kg (M), 5.34 kg (F)
Species: M. mulatta
Subspecies: M. m. brevicauda, M. m. lasiota, M. m. mulatta, M. m. sanctijohannis, M. m. vestita, M. m. villosa
Other names: rhesus monkey; macaque rhésus (French);
mono resus (Spanish); rehesusapa or rhesusmakak (Swedish);
M. m. lasiota: west Chinese rhesus macaque; M. m.
sanctijohannis: insular Chinese rhesus macaque or south Chinese rhesus macaque; M.
m. vestita: Tibetan rhesus macaque
Divided according to country of origin, rhesus macaques are referred to as Chinese-and Indian- derived.
Chinese-derived rhesus macaques include subspecies M. m. vestita, M. m. lasiota,
M. m. sanctijohannis, and M. m. brevicauda. Indian-derived rhesus macaques are found
in other countries besides India, but are still informally referred to as Indian-derived and include
M. m. mulatta and M. m. villosa (Smith & McDonough 2005). In breeding colonies at
research centers in the United States, rhesus macaques have sometimes been bred separately according to
their "country" of derivation but in other cases, crossbreeding has occurred, leading to some confusion
about the taxonomic separation of individuals used in research
(Smith & McDonough 2005).
Rhesus macaques, both Chinese- and Indian-derived, range in color from dusty brown to auburn with little
to no fur found on their reddish-pink faces. Their rumps are the same color as their faces and they have
medium-length tails that average between 207.6 and 228.9 mm (8.17 and 9.01 in) (Fooden 2000). Males and
females are sexually dimorphic, like other species of macaques, and
males measure, on average, 531.8 mm (1.74 ft) and weigh, on average, 7.70 kg (17.0 lb) while females have
an average height of 468.8 mm (1.54 ft) and an average weight of 5.34 kg (11.8 lb) (Fooden 2000; Singh &
Sinha 2004). They are quadrupedal and, depending on the type of
habitat in which they are found, can be predominantly arboreal or
predominantly terrestrial (Seth et al. 2001). Rhesus macaques are
also skilled swimmers and have been observed crossing bodies of water up to one kilometer (.621 mi) wide.
When they are seen in the water they are usually searching for food, escaping from danger, regulating
their body temperature, or playing. Swimming is a skill seen in infants as young as two days old
CURRENT RANGE MAPS (IUCN REDLIST):Macaca mulatta
The only primates with a broader geographic distribution than rhesus macaques
are humans (Southwick et al. 1996). Rhesus macaques are found ubiquitously
throughout mainland Asia; from Afghanistan to India and Thailand to southern
China (Rowe 1996; Smith & McDonough 2005). M. m. vestita, M. m. lasiota, and M. m. sanctijohannis are found in western, central,
and eastern China, respectively (Groves 2001; Smith & McDonough 2005). Another
Chinese species of rhesus macaque, M. m. brevicauda, is found on Hainan Island, off the southwest coast of China.
The Indian-derived rhesus macaques are separated by region with M.
m. villosa found in the Kashmir and Punjab region of India (the northern
part of the country), Pakistan, and Afghanistan and M.
m. mulatta found in India, Bhutan,
Burma, Nepal, Bangladesh, Thailand, Laos, and Vietnam (Groves 2001; Smith & McDonough
2005). It is likely that there will be additional subspecies added and M.
m. mulatta will be reclassified into several more distinct subspecies based
on genetic and morphological differences (Groves 2001).
A free-ranging colony of rhesus macaques was established in 1938 on an island in the Caribbean.
Introduced to Cayo Santiago, Puerto Rico, rhesus macaques have been studied under semi-natural
conditions for almost 70 years and have provided an unprecedented resource for information about
behavior, population demography, and long-term histories of individuals' social and physical
development (Rawlins & Kessler 1986a). Furthermore, with the establishment of this colony of
free-ranging macaques came the birth of a new field of study, sociobiology, pioneered by Stuart
Altmann who observed rhesus monkeys on Cayo Santiago and worked with notable sociobiologist
E.O. Wilson (Bercovitch pers. comm.).
Rhesus macaques are the most studied nonhuman primate, both in the field and in laboratory settings,
though most of the field research comes from rhesus macaques in India (Richard et al. 1989). One
of the notable early field researchers of rhesus monkeys is Charles Southwick, who began surveying
them in 1959 (Seth 2000). Donald Lindburg has been another force in rhesus macaque studies, assessing
the abundance of rhesus in India as well as reporting declines in the population which was important
at the time of their export (Seth 2000; Smith & McDonough 2005).
Because they are found in such a broad geographic area, it is difficult to concisely summarize the types of habitats rhesus macaques populate. In the most general terms, they are found in both tropical and temperate habitats including semidesert, dry deciduous, mixed deciduous and bamboo, and temperate forests as well as in tropical forests and mangrove
swamps, usually at elevations from sea level to 2000 m (6561 ft), but they have been seen at elevations up to 4000 m (13,123 ft)
in China and northeastern India (Seth & Seth 1986; Fooden 2000; Srivastava & Mohnot 2001). Rhesus macaques are also found in areas close to humans in urban settings or near cultivated fields (Southwick et al. 1996).
In the northernmost part of their range, the rhesus of the Taihang Mountains in China live in a
secondary deciduous forest at elevations between 300 and 1200 m
(984 and 3937 ft) with a temperate climate and cold, snowy winters similar to the climate of the central,
Midwestern United States (Qu et al. 1993). In this region, there are hot, rainy, and humid summers with
severely cold and dry winters, and temperatures ranging between -20° C (-4° F) and 40° C
(104° F) during the year. Annual rainfall averages 641 mm (2.10 ft), with the rainiest period
lasting from June to August (Qu et al. 1993). This is similar to the climate of the region of Pakistan
where they are found, but the habitat in Pakistan is dominated by mixed evergreen and deciduous forests
that are highly disturbed (Goldstein & Richard 1989). In their tropical range in China, and similarly in
Burma, Laos and Thailand, the rainy season lasts from May to October with annual rainfall averaging 1575
mm (5.17 ft). Temperature is more stable in India and northern China throughout the year, ranging between
22° C (72° F) and 28° C (82° F). The habitat includes primary and secondary tropical and
dry evergreen forests and bamboo forests (Jiang et al. 1991; Southwick et al. 1996; Borries et al. 2002).
In India, rhesus macaques are found in flat, cultivated areas, where agricultural fields dominate the landscape and
in the plains, foothills and mountainous regions where habitat includes cultivated fields, tropical
forests and dry, deciduous forests. Average annual rainfall ranges between 420 and 2150 mm (1.38 and 7.05 ft),
depending on elevation, and annual range in temperature is between -4° C (25° F) and 48° C (118° F)
(Seth & Seth 1986). During the hottest parts of the year, groups in the Himalayan region of India migrate to
higher elevations where cooler temperatures persist throughout the summer months (Seth et al. 2001).
In urban areas of India, they are found on roadsides, canal banks, in railway stations, villages, towns,
and temples (Richard et al. 1989). It is estimated that 48.5% of rhesus macaques in northern India live in villages, towns, cities, temples and railway stations where they are in close and frequent contact with
people at all times. About 37.1% of the population lives with some human contact on roadsides and canal
banks and only 14.4% of the rhesus macaques in the northern part of the country live in isolation from humans
and do not rely on them at all for food (Southwick & Siddiqi 1994).
Rhesus macaques are exceptionally adapted to coexisting with humans and thrive near human settlement, in both
urban and agricultural areas. It is impossible to characterize their "natural" diet without considering the
impact of humans. Because they are found in higher densities in areas of human disturbance compared to forests,
in some areas rhesus macaques derive, both directly and indirectly, a substantial part of their diet from human
activities (Richard et al. 1989). In fact, up to 93% of their diet can be from human sources, either from direct
handouts or from agricultural sources (Southwick & Siddiqi 1994). Rhesus macaques are
omnivores and feed on a wide array of plant and invertebrate products.
By raiding crops, they have access to a huge variety of cultivated fruits
and vegetables, and in highly urban areas, they forage by picking through
garbage (Goldstein & Richard 1989; Richard et al. 1989). Throughout their range and especially in India, they
inhabit temples and are fed as a form of worship by local people (Wolfe 2002). Some of the most common foods
given to rhesus macaques in temples include bread, bananas, peanuts, seeds, other fruits and vegetables, and
assorted miscellaneous foods like ice cream and fried bread (Wolfe 1992). In less human-influenced areas, they
focus on fruits, flowers, leaves, seeds, gums, buds, grass, clover, roots, bark, and they supplement their diet
with termites, grasshoppers, ants, beetles, and mushrooms. Rhesus macaques also eat bird eggs, shellfish, and
fish (Fooden 2000). During the driest parts of the year, they may even eat the dirt from termite mounds (Lindburg 1971).
On Cayo Santiago, the rhesus macaques also consume dirt possibly because the mineral composition of the soil on
the island is similar to pharmaceuticals used in humans to treat upset stomach. The Cayo rhesus may be eating dirt
to relieve the discomfort associated with intestinal parasites (Knezevich 1998).
At higher elevations, where seasonal snowfall restricts food sources, rhesus macaques are restricted to eating the
leaves of evergreen trees and bark as well as a few berries that grow in winter. During the winter months at high
elevations, rhesus macaques suffer from food and climate stress and have higher levels of mortality if the cold
weather lasts too long (Qu et al. 1993).
Home range size and day range length are dependent on habitat in rhesus macaques. Temple, village, and urban
rhesus macaques have small home ranges between .01 and 3.0 km² (.004 and 1.16 mi²) in
size because they derive almost all of their food from human visitors leaving offerings, crop raiding, or
opportunistic foraging on human byproducts (Seth & Seth 1986). The
day ranges for these urbanized areas are variable but the average is about 1.15 km (.715 mi) (Fooden 2000).
In more forested areas of India, home range size can be up to 15 km² (5.79 mi²), but rhesus
monkeys only move, on average, 1428 m (.887 mi) per day (Lindburg 1971). In China, home ranges vary in size from
.1 to .72 km² (.039 to .278 mi²) near villages, while in mountainous areas, home ranges are
much larger and span between 11 and 22 km² (4.25 and 8.49 mi²) but average 16
km² (6.18 mi²) (Southwick et al. 1996). Daily path lengths in this environment range from
1050 to 3500 m (.652 to 2.17 mi) (Makwana 1978).
Both climate and season affect the timing of the onset of daily activities as well as the type of activities
undertaken. In the warmest times of the year, rhesus macaques spend more time resting than during more
temperate months (Seth & Seth 1986; Seth 2000). Home ranges of rhesus macaques overlap and groups have high
frequencies of intergroup contact, which is characterized by generally mild social interactions (Melnick et al. 1984).
Across all habitat types, feeding and resting are the major activities of the rhesus macaques' day and they spend
the rest of their time traveling, grooming, playing, and other activities (Seth & Seth 1986).
Potential predators of rhesus macaques include raptors, dogs, weasels,
leopards, tigers, sharks, crocodiles, and snakes (Fooden 2000).
Because of their anatomical and physiological closeness to humans, the relative
ease at which they can be maintained and bred in captivity, and the available
supply from India, rhesus macaques have long been the nonhuman primate of choice
on which to conduct research on human and animal health-related topics (Mitruka
1976). Some of the direct benefits to human health that would not have been
possible without the use of rhesus macaques include: development of the rabies,
smallpox, and polio vaccines, discovery of rhesus factor in blood, creation
of drugs to manage HIV/AIDS, understanding of the female reproductive cycle
and development of the embryo, propagation of embryonic stem cells, and a number
of behavioral discoveries (Mitruka 1976; Anonymous 2005).
Content last modified: July 20, 2005
Written by Kristina Cawthon Lang. Reviewed by Fred Bercovitch.
Cite this page as:
Cawthon Lang KA. 2005 July 20. Primate Factsheets: Rhesus macaque (Macaca mulatta) Taxonomy, Morphology, & Ecology . <http://pin.primate.wisc.edu/factsheets/entry/rhesus_macaque/taxon>. Accessed 2015 July 1.