Year of The Monkey: Highlighting the Rhesus Monkey

By 02/11/2016February 13th, 2018Education

This is George. He is happily retired at OPR Coastal Primate Sanctuary. Since it is The Year of the Monkey, we will feature a different monkey species every month.
rhesus George in the pool
Here is
The Life of a Rhesus Monkey
by Viridiana Fosnow, Primates Incorporated Volunteer

Rhesus monkeys are Old World monkeys and their natural range includes Afghanistan, Pakistan, India, Southeast Asia, and China.(1)

The fur of the rhesus monkey is pale brown or grey on top fading to the underside, and the naked face and rump are bright red in adults. It has large cheek pouches which it uses to store food when foraging.(3)

The rhesus macaque is a charismatic species.(3) This is a small monkey with a long tail that helps it to stay balanced and to leap. It has close-cropped hair on its head, which accentuates its very expressive face.(2)

Habitat
Rhesus have the largest geographical range of any primate in the world other than humans.(2)

These intelligent animals can adapt to many habitats, and some can even become accustomed to living in human communities. This is most common in India, where Hindus regard the animals as sacred and usually leave them undisturbed.(1)

In the most general terms, rhesus macaques are found in both tropical and temperate habitats including semi desert, 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 (6,561 ft.)—but they have been seen at elevations up to 4000 m (13,123 ft.) in China and northeastern India.(4)

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.(4)

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. In urban areas of India, they are found on roadsides, canal banks, in railway stations, villages, towns, and temples.(4)

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.(4)

Morgan Island off of South Carolina is known to be home to some rhesus macaques that were deliberately moved there. This indicates they do very well in any type of environment.(2)

Diet
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.(4)

The rhesus monkey’s typical diet includes roots, fruit, seeds, and bark, but also insects and small animals.(1) Pine needles are part of their food supply. Leaves also make up their daily dietary intake.(2)

Throughout their range and especially in India, they inhabit temples and are fed as a form of worship by local people. 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.(4)

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. During the driest parts of the year, they may even eat the dirt from termite mounds.(4)

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. 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.(4)

Behavior & Social Structure
Rhesus macaques live in active troops that can include as many as 40 members–approximately 4 times as many females as males.(2) There is a complex hierarchy through the females. The lineage of the young in the group can be traced to the dominant females. Though these monkeys are good climbers (and swimmers), troops spend a lot of time on the ground.(1)

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. Home ranges of rhesus macaques overlap and groups have high frequencies of intergroup contact, which is characterized by generally mild social interactions.(4)

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.(4)

Rhesus Macaques are being used in the process of developing medicines and medical technology. The development of stem cell technology, on which so many hopes are pinned today, was initially based on monkeys.(5)

The name rhesus has been extended to the hereditary blood antigen ‘Rh-factor’, which was discovered on the red blood cells of rhesus macaques and was also found to be present in humans.(3)

Currently, there are approximately 105,000 monkeys living in U.S. laboratories (~8,000 are living in Madison, WI).(7) It is unknown how many rhesus monkeys comprise the 105,000 number, but Primates Incorporated is aware that Old World Monkeys such as the rhesus macaque and long-tail Macaque are prevalent species of monkeys residing at sanctuaries after being retired from research facilities.(8)

Primates Incorporated believes that if society is using monkeys because of their similarities to humans, the very least society can do is give back to the monkeys whenever possible after their research is complete.(6)

Sources:
1. http://animals.nationalgeographic.com/animals/mammals/rhesus-monkey
2. http://www.monkeyworlds.com/rhesus-macaque
3. http://www.arkive.org/rhesus-macaque/macaca-mulatta
4. http://pin.primate.wisc.edu/factsheets/entry/rhesus_macaque
5. http://www.mpg.de/8429495/research-primates-benefits
6. https://www.primatesinc.com/about/faq
7. https://www.aphis.usda.gov/animal_welfare/downloads/7023Animals%20Used%20In%20Research%202014.pdf
8. https://www.primatesinc.com/about/residents