The Rhesus macaque is a monkey of the Old World. They are either pale brown or gray, usually with a pink face. Their tails are quite long, they have a rib cage that is wider than average, with dorsal scapulae, and they have thirty-two teeth. They are charismatic monkeys and like to have fun and can be cheeky. Their coats have faded undertones on the underside. Their faces are furless and in adults are bright red, and adults also have bright red rumps. They have large cheek pouches for storing food while out foraging.
Rhesus macaques are native in northern India, Bangladesh, Pakistan, Burma, Nepal, Thailand, Vietnam, Afghanistan, southern China, and several neighboring areas. Some live in flatlands, while in Pakistan and northern India they live in the Himalayas as high as 3,000 meters. They are able to live in a range of climatic extremes, from hot, dry temperatures in deserts, to cold temperatures which fall in winter to far below freezing.
Rhesus macaques are social, diurnal and both terrestrial and arboreal animals. They walk using four limbs, walking on the ground on both on their toes and on the soles of their feet. They are very active and loud. They like being in water and can swim well. They form groups of as many as 200 individuals, and when the size of a group reaches 80 to 100, a subgroup of females can split off to create a new group. Generally groups are made up of several unrelated males, with many closely related females. Males and females within a group demonstrate a preference for high-ranking individuals of the opposite sex. Rhesus monkeys are not territorial. Every group of individuals generally has its own sleeping area. Confrontations between different groups are rare. When groups meet, usually the weaker group avoids the stronger one.
Rhesus macaques are herbivores animals, eating seeds, roots, bark, fruits and cereals. They do not eat meat. When the monsoon approaches, ripe fruits provide them with a much-needed source for water. When rhesus macaques live far from a water source, which is not common, they get water from dewdrops off tree leaves.
Rhesus macaques are polygynandrous when males and females have multiple mating partners during a breeding season. Breeding seasons vary widely amongst populations. Those monkeys living in areas with cold winters mate in the autumn and those living where there is less pronounced seasonal changes have less well-defined seasons for mating. The gestation period lasts about 165 days, and usually a single young is born. Newborns nurse for about a year. Females are sexually mature at 2.5 to 3 years old and males at 4.5 to 7 years old.
The Rhesus macaque living in the wild is threatened, but a large population is captive across the world for biological, medicinal and psychological research, especially for studies about perception, learning and behavior. They raid crops in India but there the Hindu religion considers them to be sacred animals, so they avoid human persecution.
The IUCN Red List and other sources don’t provide the number of the Rhesus macaque total population size. Currently this species is classified as Least Concern (LC) on the IUCN Red List.
Rhesus monkeys may help with the dispersal of seeds. Being a species that is preyed upon, they may affect populations of predators.