enrichment

Kathryn Bayne, M.S., Ph.D., D.V.M., DACLAM, CAAB

AAALAC International

Macaques

for nonhuman primates
Macaques

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Macaques

Introduction

Nonhuman primates maintained in captivity have a valuable role in education 

and research. They are also occasionally used in entertainment. The scope of 

these activities can range from large, accredited zoos to small “roadside” exhibits; from national primate research centers to small academic institutions with 

only a few monkeys; and from movie sets to street performers. Attached to these 

uses of primates comes an ethical responsibility to provide the animals with an 

environment that promotes their physical and behavioral health and well-being. Thus, an obligation is entailed that those individuals/institutions caring for 

captive primates should make every effort to ensure adequate veterinary care and 

husbandry are provided, that the animals are housed in appropriate facilities, 

and that as broad a range of species-typical behaviors are able to be expressed by 

the animals as is possible for the captive environment.

This book serves as an introduction to the basic behavior and environmental 

enrichment of several species of nonhuman primates that are more commonly 

used in education, research and entertainment. In many ways, this book is 

meant to be a “how to” manual; it is not intended to be a broad scientific review 

of the primate behavior and enrichment literature. The fundamental premise 

taken throughout each chapter is that for an enrichment program to be effective, there must be a basic understanding of the biology and behavior of the 

primate species. The species addressed in this series are: baboons, capuchins, 

chimpanzees, macaques, marmosets and tamarins, and squirrel monkeys. Each 

species-section can be read as a stand-alone document without need to reference 

the other sections. This then allows the user to distribute the different sections 

to personnel caring for the specific animals. 

Each section is divided into five parts: 1) Background, comprised of the habitat 

of the primate, the physical features of the primate, its psychological and/or so

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Macaques

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ii

social behavior, and its mating and reproductive behavior; 2) Social World; 

3) Physical World; 4) Special Cases, describing any age-related considerations 

and concerns associated with individual housing; and 5) Problem Behaviors. 

The content of this series has been provided by members of the Association of 

Primate Veterinarians (APV) and the American Society of Primatologists (ASP) 

who have special expertise in the species addressed. This book is intended to be 

a primer because it is, indeed, an introduction to the subject of environmental 

enrichment for primates housed in a diversity of conditions. A list of references 

and/or other resources (principally on-line) is provided at the end of each chapter that provide additional guidance. The use of scientific references has been 

limited, but should the reader desire more information about a specific subject, 

the links at the end of the sections will provide direction to obtaining additional 

detailed information. Readers are also directed to the National Research Council 

publication, the Guide for the Care and Use of Laboratory Animals (1996) and 

the U.S. Department of Agriculture’s (USDA) Animal Welfare Regulations to 

review the regulatory requirements of the Public Health Service and the USDA 

for the provision of environmental enrichment.

The APV and ASP wish to thank the Office of Laboratory Animal Welfare, in 

particular Ms. Carol Wigglesworth and Dr. Axel Wolff; the U.S. Department of 

Agriculture/Animal Care, in particular Dr. Chester Gipson; and Ms. Dale Feurer, editor, and Ms. Lori Wieder, graphics and layout production, for their assistance with this project. The authors acknowledge the helpful contributions of 

Dr. David J. Shepherdson, Conservation Program Scientist, Metro Washington 

Park Zoo; Ms. April D. Truitt, Director, Primate Rescue Center, Inc.; and Ms. 

Kathleen Conlee, Program Officer, Humane Society of the United States. Special thanks also go to the chapter authors Dr. Christian Abee, Dr. Kate Baker, 

Dr. Linda Brent, Dr. Thomas Butler, Dr. Jeffrey Fite, Dr. Dorothy Fragazy, Dr. 

Jeffrey French and Dr. A. Michele Schuler, and to the reviewers from the American Society of Primatologists and the Association of Primate Veterinarians.

—Kathryn Bayne, M.S., Ph.D., D.V.M., DACLAM, CAAB

Editor, Working Group

This project is dedicated to the memory of Dr. Sylvia Taylor, Veterinary 

Medical Officer, Animal Care, U.S. Department of Agriculture, who 

was a proponent of providing enrichment to nonhuman primates and 

was generous in sharing her knowledge and expertise in this regard. 
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Macaques

Background

Habitat

The macaques represent a collection of approximately 20 species of monkeys, 

most of which are found in Asia. They occupy a wide geographic range that is 

considered second only to man in its extent. In this range, the habitat occupied 

by macaques varies from near desert to rainforest, and from sea level to snowy 

mountain tops. Some macaques spend the majority of their time in trees, while 

others are predominantly ground-dwellers. Many live in close proximity to 

human beings; the rhesus monkey is sacred to Hindus and is often found near 

temples in India and Nepal.

 

Physical Features 

In general, the macaques have a 

medium-sized body, with a stocky 

build. Animals belonging to the 

smallest species weigh approximately 

13 pounds, while representatives of 

the largest species weigh an average of 40 pounds. Tail length varies 

among the different species. All 

macaques have long, sharp canine 

teeth and finger nails that can pose 

a risk to human handlers through either bite or scratch wounds. They also have 

cheek pouches and a fully opposable thumb. The opposable thumb gives these 

animals the ability to manipulate objects (e.g., cage latches) with great precision. 

They feed on both animal and vegetable resources and have a highly varied diet. 

Macaques are primarily active during the daylight hours, and most species sleep 

in trees at night. 

Rhesus (Macaca mulatta) monkey with cheek 

pouches full of food (photo courtesy of K. Bayne).

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Macaques
Macaques

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Behavior 

As a rule, the macaques are social animals, living in groups of multiple males 

and females; the sex ratio typically reflects more females than males in a group. 

Even for the same species, group size tends to be smaller when the home range 

size is also smaller (e.g., when constrained by human activities). Within these 

groups, individuals are ranked according to dominance (hierarchies), with the 

higher ranking animals doing more of the successful breeding and having first 

access to food and other desirable resources. Often it is the rank of the mother, 

rather than the father, that determines the rank of offspring. Young males may 

be evicted from their birth group as they approach puberty, forming temporary 

“bachelor” groups until they join a new group. Wounding of animals can occur 

when challenges for dominance occur.

Because these animals 

rely in large part on visual 

communication, they use 

a number of facial signals, 

often accompanied by vocalizations, to threaten or 

to make friendly overtures. 

Threat displays include 

opening the mouth in the 

shape of an “O”, a direct 

stare, raising the eyebrows 

quickly and repeatedly, 

flapping the ears, a jerky head-bob, shaking an object in their environment such 

as a tree branch or cage door, slapping the ground, or charging with intent to 

fight. Occasionally, a lack of compatibility between animals can be detected 

simply by the increased physical distance maintained between them. Behavioral 

indicators of compatibility between animals include social grooming, lip-smacking, and sitting in close proximity. Food sharing has also been used to assess 

compatibility between pairs of animals.

Social grooming is an integral part of forming affiliations

(photo courtesy of K. Rasmussen).
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Macaques

Mating and 

Reproduction

The reproductive 

cycle of macaques 

is characterized by a 

seasonal estrus period, 

with menstrual cycles 

occurring throughout 

the year. Females have 

been reported to begin 

cycling as early as approximately 1.5 years, 

although a more typical 

age is 2.5 years. Most 

species of macaques 

exhibit swelling and 

reddening of the skin 

of the rump, perineum, 

and occasionally arms, 

legs and face (referred 

to as “sex skin”). The 

swelling and reddening becomes more 

pronounced from 

beginning to end of the 

menstrual cycle. Exceptions to this are bonnet macaques and toque monkeys, 

who do not have marked sex skin. Menopause occurs in the macaques, with the 

number of menstrual cycles decreasing each year when the animal reaches her 

third decade of life. 

In general, the female actively solicits mating by the male (again, the bonnet macaque is an exception to this). Usually, the dominant males in the group breed 

the females more often, although less dominant males in a group have been 

reported to breed and reproduce successfully. The rhesus monkey’s gestation 

period is between five and six months. The infant is quite dependent upon the 

mother, and the current preference is to leave the infant with its mother until 

approximately one year of age to help ensure adequate development of social, 

particularly maternal, skills by the developing infant.

Social defense of territory (photo courtesy of K.Rasmussen).
Macaques

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Social World

Because of the intrinsic social nature of macaques, pair or group housing of 

compatible animals is extremely important. It is well-known that raising a macaque alone, without the company of other macaques of the same species, will 

result in that animal expressing a pattern of abnormal behaviors that can become 

self-destructive. Even the 

behavior profiles of adult 

animals housed alone can 

degenerate into inciting 

these abnormal behaviors, which may include 

repeated pacing, circling, 

or somersaulting; hyper-aggression; depression; and self-injurious 

behavior, including hair 

plucking or self-biting. 

(See section on “Problem 

Behaviors”). 

While group or pair 

housing is strongly 

recommended for macaques, care should be 

taken in doing so. Since 

these primates establish dominance hierarchies and space is limited in captivity, 

the macaque wishing to flee the dominant animal has no place to fully escape. 

This can result in unresolved, increased aggression between the animals as well 

as wounding (and possibly killing) of one or more animals. 

Larger groups of animals that previously have been living in smaller stable 

cohorts should not be formed, because this will increase fighting between the 

smaller, pre-established groups. A better approach is to place unfamiliar animals 

together in a new enclosure at the same time. In this way, coalitions have not 

already been formed, and each macaque must establish its own place in the hierarchy without support from other animals.

Evidence of hair-plucking behavior, a type of self-injurious 

behavior (SIB) on the leg of this macaque

(photo courtesy of K. Bayne).

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Macaques

One approach to forming pairs of macaques is provided at the end of this chapter. The key steps include the following: 

• Introducing the animals into an area that they do not consider as their 

territory

• Assessing facial expressions, postures and physical distance between the 

animals 

• Proceeding slowly in forming pairs

• Planning ahead to have a way of separating animals should the fighting 

become intense (e.g., a panel to slide between cages, use of water, etc.)

• Ensuring the safety of people performing the animal introductions 

• Providing ongoing 

monitoring 

of animal 

interactions, 

because animal 

relationships can 

change over time

Using the natural 

social structure of the 

macaques will assist in 

forming compatible 

pairs or groups of monkeys. For example, 

because macaques will form bachelor 

troops, often males can be pair-housed 

successfully. Successful pairings of a young 

macaque with an older animal (so that the 

dominance hierarchy is clear and fighting is 

minimized) also have been reported. 

Offering vulnerable areas of the body to be groomed by another 

animal indicates a degree of trust and affiliation between the animals 

(photo courtesy of K. Bayne).

Providing three-dimensional space in the primary 

enclosure, using Primahedrons®

(photo courtesy of K. Bayne).
Macaques

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Physical World

Housing 

Macaques have been housed successfully in a variety of types of housing, 

including island environments, corrals, corn cribs, indoor-outdoor runs, pens 

and cages. Regardless of the enclosure design or size, it must be sturdy enough 

to withstand being shaken and chewed on by its inhabitants. Because of the 

animals’ tendency to flee upward when escaping a perceived threat, they benefit 

from perches, shelves or other structures that increase the three-dimensional 

space of the enclosure. Generally, older macaques prefer a non-moving shelf or 

perch, while the younger ones will readily use swings. Because macaques can 

strangle on lengths of chain, swings should be short in length and/or constructed of materials that cannot loop around the neck, such as flexible polyvinyl chloride (PVC) tubing. Similarly, ropes can be picked apart or chewed on, and this 

may result in a gastric obstruction. Thus, in most cases, ropes of cotton, sisal or 

jute should be avoided.

In general, macaques should not 

be exposed to cold or wet weather 

without a method for them to 

conserve body heat. Japanese 

macaques living in the snowy 

mountains of Japan manage to 

stay warm by soaking in natural 

hot springs. A number of captive macaques, however, have lost 

parts of their tails or one or more 

digits to frostbite. This problem can be reduced or prevented by providing them 

with supplemental heating or a shelter. 

During conditions of high heat and humidity, macaques may overheat if they 

undergo a physical stress, such as being chased around an enclosure. Providing 

macaques with a shallow and indestructible pool in which to swim and cool off 

can be an asset to macaques housed outdoors in warmer climates. The swimming pool should be shallow, to prevent animals from drowning, and resistant 

to deterioration from chewing. The pool should be cleaned routinely to provide 

animals with good quality water for swimming.

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A horse water trough, shown here, serves as a swimming 

pool for young macaques (photo courtesy of K. Bayne).
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Macaques

Enrichment

The macaques are curious and intelligent animals. Providing them with opportunities to investigate and explore their environment is enriching for them. 

This can be accomplished by maintaining toys in the animals’ enclosures. Since 

macaques have color vision, the toys (also known as manipulanda) should be 

of different colors; they can also be of different shapes and texture. Because 

the monkeys will chew on these toys, they should be relatively durable, such as 

heavy-duty dog toys. Toys should be removed from the enclosure when they become sufficiently damaged that the primate might swallow or choke on a piece. 

Rotating different toys in the enclosure and removing them periodically will 

help to keep the toys novel and increase the animals’ interest in them.

Flexible PVC tubing 

can be installed in the 

primary enclosure to 

simulate branches for 

swinging (photo courtesy 

of K. Bayne).

A variety of toys used with 

macaques (photo courtesy of K. 

Bayne and S. Dexter).

The damage inflicted on toys after usage 

by macaques. Small remnants can pose 

a choke hazard to the animals (photo 

courtesy of K. Bayne and S. Dexter).
Macaques

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A very successful way to fulfill these animals’ inclination to explore and investigate 

is to give them the opportunity to forage 

(or search) for food. Since many primates 

will spend up to 70% of their waking 

hours in foraging-related activities, offering captive primates the opportunity to 

engage in this behavior can be important 

in preventing the development of abnormal behaviors. Numerous in-house and 

commercially produced devices are available, including toys that simply 

hold the food item and require the 

monkey to fish for or push it out. 

Also available are containers with 

finger holes or slots through which 

the monkey removes the food item, 

as well as puzzle boards in which 

the monkeys must manipulate the 

food item though a maze before it 

reaches a hole large enough from 

which the food can be retrieved. 

Food may be hidden throughout 

the enclosure to encourage searching behaviors. Food items may also 

be ground up into small pieces 

or pre-purchased as “crumbles” 

and then placed on an Astroturf®

or artificial fleece foraging board. 

The small size of the food particle 

encourages manual dexterity and 

extends the amount of time the animal spends searching for and eating the 

food. Food treats, as enrichment, should not be offered in such quantity that the 

animal ignores its more nutritional daily diet or gains excessive weight. Many 

commercially available food treats come in a variety of flavors and are nutritious. 

Food treats may be dispensed from 

puzzle balls (photo courtesy of K. Bayne 

and S. Dexter).

Wedging food treats inside a Kong® toy is another 

way to extend the animal’s time spent in “foraging” 

(photo courtesy of W. Brandon).
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Macaques

This animal forages 

for food “crumbles” in 

an artificial shearling 

foraging/grooming board 

(photo courtesy of K. 

Bayne).

Special Cases

Age-related Considerations 

The macaques are long-lived animals, with reports of some animals living in 

captivity over 30 years. This lifespan entails a commitment of considerable duration, with substantial, changing needs of the animal over the course of its life. As 

with other species of primates, the design of the environment should take into 

account the age of the macaque. For example, older monkeys will develop arthritis, limiting their ability to jump onto perches, swing, or otherwise navigate 

their enclosure. Older primates can also have reduced vision capabilities, thus 

further limiting their ability to move around the enclosure and interact with 

other animals or people. 

Conversely, young animals are very active and curious. The enclosure design 

should allow them to express these characteristics without compromising their 

physical safety. Young animals also are particularly sensitive to the effects of 

social deprivation and should be housed with other primates of the same species 

whenever possible.

Individual Housing 

The circumstance in which only one macaque is housed on the premises should 

be avoided. If several macaques are housed individually in cages, they should 

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Macaques

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be able to see, hear and smell each other. If possible, individually caged animals 

also should have access to visual barriers in order to avoid being seen by other 

animals, should they so choose. It is recommended that if an animal cannot be 

socially housed, other forms of enrichment (e.g., toys, foraging opportunities) 

should be provided to compensate for the lack of social stimulation.

Susceptibility to Disease

Because of their close genetic relationship to humans, nonhuman primates 

can be susceptible to human diseases. Of particular concern is the exposure of 

macaques to tuberculosis from a human. Tuberculosis is a highly contagious, 

fatal disease in Old World Monkeys. Routine testing of the animals is highly 

recommended. Macaques are also susceptible to measles virus, and will show 

a rash similar to that of people having the disease. Most colonies of macaques 

are vaccinated for measles virus. Because numerous individuals may be assisting 

with the enrichment program (including volunteers), close attention should be 

paid to the possible transmission of diseases from humans to macaques.

Problem Behaviors

The most appropriate behavioral management program houses macaques in 

a sufficiently enriched and safe environment to prevent the development of 

abnormal behaviors. Nevertheless, personnel caring for macaques should be 

adequately trained and able to recognize the occurrence of abnormal behavior in 

macaques. It is important to note that not all macaque species exhibit the same 

types of abnormal behavior or to the same degree. Some abnormal behaviors are 

initially quite subtle in their expression, but over time can become more obvious 

and harder to stop. Abnormal behaviors include repetitive movements, such as 

pacing, circling, rocking, spinning, somersaulting and bouncing. Cage-licking, 

self-clasping, self-sucking, masturbation, “saluting,” and eating feces are some 

other aberrant, repetitive behaviors. Abnormal behaviors in macaques also can 

hurt or injure the animals, as in the case of hair plucking, self-biting and head 

banging. 

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Macaques

Abnormal behaviors are an undesirable consequence of captive housing, reflecting an inadequate environment for maintaining the animal. Preventing the 

development of abnormal behaviors is critical, because they are difficult to stop 

once they start. In some cases, socially housing an animal that previously was 

singly housed can decrease the expression of abnormal behaviors, presuming 

that the animals are compatible. Progress has been made in reducing the occurrence of hair-plucking behavior by providing the animal with a fleece covered 

Plexiglas® board or coconut, thereby giving the monkey something else to pluck. 

However, redirection of an abnormal behavior is not a “cure” and should only 

be regarded as a temporary correction. Although occasionally self-biting behavior can be redirected to a toy, recent evidence has shown that some drugs will 

reduce the occurrence of this behavior more reliably. In this case, the veterinarian should be consulted.

Safety Issues

In general, the least amount of restraint necessary to accomplish the task should 

be used when working with macaques. However, because macaques can seriously 

threaten people’s safety, the method of restraint should also ensure the safety of 

both the personnel and the animal. Restraint can be achieved by hand (e.g., with 

younger animals), by the use of various drugs such as ketamine hydrochloride, 

or by the use of equipment such as transport cages, the pole and collar system, 

or tunnels to move animals from one location to another. Macaques can be 

trained to cooperate in a variety of procedures, thus reducing the amount of restraint necessary. Examples include training the animals to move into a transport 

box to be removed temporarily from their home cage or training an animal to 

extend its arm or leg for a blood sample to be withdrawn. Such training is an 

important part of the enrichment program as it gives the animal some control 

over the situation and reduces the stress the animal might otherwise experience 

during basic husbandry and medical procedures in which it was not actively 

cooperating. Appropriate protective equipment, including gloves, mask, eye 

protection, etc., should be worn when working closely with macaques.

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Macaques

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In addition, the provision of many 

types of enrichment devices involve 

either attaching the device to the 

cage, reaching into a cage to place the 

enrichment, or entering the primates’ 

enclosure. These can place the individual at risk of being grabbed, bitten, 

or scratched. Macaques are a frequent 

carrier of Herpes B-virus, which is 

asymptomatic in the animals but can 

be fatal to humans. This viral infection can be transmitted from animal 

bites, scratches, splashes, needle 

stick injuries, and other contact with 

mucous membranes or broken skin 

with infected body fluids (e.g., saliva, 

urine) from the monkey. Personnel 

should wear appropriate protective 

equipment, concomitant with the 

potential for exposure.

Resources

National Research Council. 1998. The Psychological Well-Being of Nonhuman 

Primates. Washington, DC: National Academy Press. 

National Research Council. 2003. Occupational Health and Safety in the Care 

and Use of Nonhuman Primates. Washington, DC: National Academy Press.

Nowak R. 1999. Walker’s Primates of the World. Baltimore, MD: The Johns 

Hopkins University Press. 

National Research Council. 1996. Guide for the Care and Use of Laboratory 

Animals. Washington, DC: National Academy Press.

U.S. Department of Agriculture. 1991. Animal Welfare Regulations. Title 9, CFR 

Part 3, Federal Register, Volume 56, No. 32.

http://www.bioserv.com (a company supplying food treats and other 

enrichments)

http://www.ottoenvironmental.com/Default.asp (a company supplying 

enrichment items)

http://www.enrichment.org (Web site for “The Shape of Enrichment”)

A transfer cage is placed against the door of the 

home cage, which is then opened, to move an 

animal without hand restraint or the use of drugs 

(photo courtesy of S.Dexter).

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Macaques

http://www.awionline.org/Lab_animals/biblio/enrich.htm (a bibliography of 

enrichment articles)

http://www.brown.edu/Research/Primate/ (Web site for Lab Primate Newsletter, 

a publication with behavior and enrichment articles)

http://www.aazk.org/committees/enrichment/comm_enrichment_title.php 

(Web site for the enrichment committee of the American Association of Zoo 

Keepers)

http://www.aphis.usda.gov/ac/eejuly15.html (Web site for the U.S. Department 

of Agriculture’s “Final Report on Environment Enhancement to Promote the 

Psychological Well-Being of Nonhuman Primates”)

Common Names of the Macaques

Macaca arctoides: Stump-tailed macaque, Bear macaque, Brown stump-tailed 

macaque

M. assamensis: Assamese macaque, Assam monkey, Mountain monkey, 

Himalayan Macaque, Montane Rhesus

M. brunnescens: Muna-Butung monkey

M. cyclopis: Taiwan macaque, Taiwanese macaque, Formosan macaque, 

Formosan rock macaque

M. fascicularis: Crab-eating macaque, Cyno, Cynomolgus, Irus monkey, Java 

monkey, Kra (or Kera), Long-tail macaque, Philippine monkey

M. fuscata: Japanese macaque, Snow monkey

M. hecki: Heck’s macaque

M. maura: Moor macaque

M. mulatta: Rhesus monkey

M. nemestrina: Pig-tail macaque, Pigtail macaque, Pig-tailed macaque, Giant 

rhesus

M. nigra: Sulawesi crested macaque, Sulawesi black ape, Celebes black ape, 

Celebes ape, Celebes crested macaque, Black ape

M. nigrescens: Gorontalo macaque

M. ochreata: Sulawesi booted macaque, Booted monkey, Booted macaque

M. pagensis: Mentawai macaque

M. radiata: Bonnet macaque, Bonnet monkey

M. silenus: Lion-tail macaque, Liontail macaque, Lion-tailed macaque, Lionmaned macaque, Wanderoo, Wanderu, Ouanderu

M. sinica: Toque macaque, Toque monkey

M. sylvanus: Barbary ape, Barbary macaque, Gibraltar ape, Gibraltar macaque

M. thibetana: Père David’s stump-tailed macaque, Tibetan stump-tailed 

macaque, Tibet monkey

M. tonkeana: Tonkean macaque

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Sample Pair Housing SOP -- Macaques

Pair Housing: Following are descriptions of the five different pair housing combinations and the procedure for pairing each combination. It should be noted 

that on-going, vigilant monitoring is necessary to the successful social housing 

program. As animals mature, their relationship may change, necessitating separation of the animals and identification of new partners.

Juveniles: Two juveniles (three years of age or younger) of the same sex are 

paired together.

Place the animals in an appropriate size cage. Check the animals every hour for the 

first four hours and at least three times per day for the first week.

Adult with Infant or Juvenile: An adult (four years of age or older) of either sex 

is paired with a weaned infant or juvenile (eight months to three years) of either 

sex. 

Adult Females: Two adult females (generally cynomolgus monkeys, four years 

of age or older) are paired together, with their unweaned infants (less than one 

year of age), if applicable.

Adult Male and Female: An adult male (five years of age or older) is paired 

with an adult female (four years of age or older), for either breeding purposes or 

enrichment purposes.

Place the animals in a double cage with a clear Plexiglas® panel between them. 

If there are no signs of aggression after one hour, open the panel. Alternatively, if a 

Grooming-Contact (G-C) bar divider is available, use this first. Check the animals 

at least every hour for the first four hours and at least three times per day for the first 

week. Initially, the animals may be separated at night, until a compatible relationship is established.

Adults Males: Two adult males (four years of age or older) are paired together.

Place the males in a double cage with a clear Plexiglas® panel between them. 

Alternatively, if a G-C bar divider is available, use this first. If there are no signs of 

aggression after twenty-four hours, move the animals to a new double cage (to avoid 

territorial aggression) without a panel. Ensure that the males do not have visual contact with any breeding pairs. Check the animals at least every hour for the first four 

hours and at least four times per day for the first week. Initially, the animals may be 

separated at night, until a compatible relationship is established.

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Macaques
This series of booklets on enrichment for nonhuman 

primates was made possible through the cooperation of: 

~ Department of Health and Human Services

~ NIH, Office of Laboratory Animal Welfare (OLAW)

~ US Department of Agriculture, Animal Care

~ Association of Primate Veterinarians

~ American Society of Primatologists

For more information, contact OLAW at NIH

tel: (301) 496-7163, e-mail olaw@od.nih.gov

NIH Publication No. 05-5744

Department of Health and Human Services, 2005

enrichment for nonhuman primates