enrichment for nonhuman primates

A. Michele Schuler, D.V.M., Ph.D

Primate Research Laboratory, University of South Alabama

Christian R. Abee, D.V.M.

University of Texas MD Anderson Cancer Center

Squirrel 

Monkeys (Saimiri)
Squirrel Monkeys

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Squirrel Monkeys

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 

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Squirrel Monkeys

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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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Squirrel Monkeys

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Squirrel Monkeys

Background 

 

Habitat 

Squirrel monkeys are inquisitive, predominately tree-dwelling primates that 

spend the majority of their time in the middle level canopy of the forest. Their 

distribution includes an isolated population in the rainforest of Costa Rica 

and virtually the entire Amazon Basin of South America. In the wild, squirrel 

monkeys inhabit most types of tropical forest including both wet and dry forest, 

continuous and secondary forest, mangrove swamps, riparian habitat, and forest 

fragments. They are very flexible in their ability to adapt to different environments and, in some geographic areas, appear to prefer habitats that have been 

disturbed by humans.

 

Physical Features 

The male squirrel monkey weighs 

approximately 550-1135 grams, while 

the female weighs from 365-750 

grams. The male exhibits an increase 

in body weight-- particularly in the 

arms, shoulders and trunk of the 

body-- during the breeding season, 

referred to as the “fatted male” syndrome. This increase in body weight is accompanied by an increase in spermatogenesis. The tail of the squirrel monkey is long, but not prehensile. The legs are 

longer than the arms. The hair coat is short and dense, with coloring ranging 

from grey-green on the back of the animal to white, yellow or orange on the 

underside. There is typically a tuft of black hair on the tip of the tail.

 

Squirrel monkey in a complex, naturalistic 

environment (photo courtesy of C. Abee).
Squirrel Monkeys

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Wooden branch used as a perch (photo courtesy of C. Abee).

Behavior 

Squirrel monkeys are omnivores that eat insects, eggs, and small vertebrate 

animals, in addition to various fruits, flowers, and tender leaves. In captivity, 

squirrel monkeys can live to be 25 years of age. 

 

Squirrel monkeys primarily use all four limbs to move, employing their tails for 

balance as they navigate along tree branches. They occasionally stand on two 

limbs to walk short distances and to grasp food items with both hands. As a 

tree-dwelling species, they make use of vertical as well as horizontal space. Although they often descend to the ground or floor of their enclosure, they prefer 

to leap from perch to perch. Lacking the bone structure for sitting, they perch 

rather than sit, frequently using their tails for balance. Perches should be round 

in shape rather than flat shelves, as the development of pressure sores on the tail 

has been associated with flat shelves.

Social interactions frequently observed within squirrel monkey groups include 

grooming behaviors, “calling” (i.e., vocalizations), play, displays of aggression, 

and huddling. Vocalizations help to maintain the social organization of squirrel 

monkey troops. Squirrel monkeys use calls to enhance group coordination and 

cohesion. It has been suggested that squirrel monkeys can differentiate individuals using vocal cues and communicate within the troop even when they cannot 

see each other.

 
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Squirrel Monkeys

Communication between animals within a given social group includes olfactory, visual, and vocal signals. Olfaction is most important during the breeding 

and birthing seasons. Males use scent to determine the receptivity to mating 

of females. In addition, female monkeys use scent to identify individual infant 

animals. When cleaning the animals’ enclosures, it is beneficial to the monkeys 

to avoid strong, artificially scented products.

 

Visual cues are of primary importance in visual displays. Squirrel monkeys make 

these displays in an attempt to assert dominance or reduce tension between individuals. Visual cues involving facial expressions can be associated with fear or 

aggression. A penile display, associated with spreading of the thighs, is considered to be a dominance gesture. Enclosures should provide a place for a submissive monkey to break the stare of a more aggressive monkey. Such places are 

called “hide-boxes” and can be made from a piece of a large-diameter polyvinyl 

chloride (PVC) pipe or another impervious material.

Vocal signals are of the utmost importance for squirrel monkeys. Infants possess 

a wide repertoire of sounds, including grumbles, cackling, purrs, chucks and 

peeps. These sounds communicate the well-being of the infant to the mother. 

In adults, calls are used to signal alarm, to display general disturbance or excitement, and to establish contact with the group when visually separated. 

 

Mating and Reproduction

Social behavior in squirrel monkeys depends on the phase of the reproductive 

cycle. These monkeys become sexually mature at approximately three to four 

years of age. While reproductive efficiency declines beginning at about 12 years 

of age, they can continue to reproduce for several more years. During breeding season (December through February in the northern hemisphere), male 

monkeys tend to be more inquisitive, aggressive, and active. At the same time, 

receptive female monkeys are less likely to respond with an aggressive display 

or facial expression when approached. After the breeding season, males become 

less involved in the social group, often remaining on the perimeter of the group. 

Females tend to perch with other females of similar age. These female-female 

interactions may include infant-care sharing and grooming behaviors.

The gestation period lasts approximately 168-182 days. During the birthing season (usually May to August in the northern hemisphere), older females without 
Squirrel Monkeys

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infants will act as “baby-sitters” or “aunts,” often carrying infants for the mother. 

This maternal behavior by females other than the mother may include nursing another female’s infant. This is a common characteristic of squirrel monkey 

breeding groups. Occasionally, juvenile animals can pose a threat to nursing 

infants as they can be aggressive to the new babies. Care should be taken when 

housing expectant/new mothers with juvenile animals.

Social World

Consideration of the needs of squirrel monkeys in captivity should extend 

beyond their basic physiologic requirements. These animals possess a host of 

behaviors that define their species. Putting forth the effort to enhance psychological and physical well-being of squirrel monkeys is essential to meeting the 

needs of this species. Through a well-conceived plan of environmental enrichment, good husbandry practices and a sound program of veterinary medical 

care, anxiety and boredom can be alleviated and natural behavior typical of this 

species can be promoted.

In the wild, squirrel monkeys live 

in large social groups (“troops”) 

containing 20 to 200 animals. In 

captivity, social group size and age 

and sex ratios differ depending 

on the limitations of the housing 

available and purpose for maintaining the animals. 

Efforts should be made to house 

the highly social squirrel monkeys 

in pairs or small groups whenever 

possible. Social groups should be 

maintained with animals born 

into the social group remaining in 

the group as long as is possible. Generally, it is recommended that social groups 

maintained in captivity include only one or two adult males per group, because 

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Carrying of an infant squirrel monkey

(photo courtesy of C. Abee).
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Squirrel Monkeys

fighting may develop among males if more than two are housed together within 

the social group. Most of the time, females of varying ages can be housed in 

social groups of two or more with only occasional difficulties with incompatibilities of group members. In fact, housing multiple females per group provides 

breeding animals the social structure necessary to reproduce efficiently. To 

maximize breeding efficiency, as many as 20 females can be housed with a single 

male. An optimal ratio, however, is one male per eight to ten females.

 

Groups that have access to a semi-natural environment with more living space 

are able to accommodate more adult males within the same groupings due to 

the increased complexity and size of the environment, the possibility of emigration to an adjacent group within the enclosure, and the increased provision of 

hiding areas. 

A social group of squirrel monkeys (photo courtesy of C. Abee).
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A hiding area for squirrel monkeys

(photo courtesy of C. Abee).

Physical World

 

Housing

Both indoor and outdoor group 

pens can be designed for squirrel 

monkeys. Physical comfort of the 

animals is important in reducing 

stress and promoting the well-being of colony members. Animals 

in outdoor pens have the opportunity to control aspects of their 

environment by moving through 

their pen (e.g., sun or shade). The 

animals are generally free to seek 

the place they wish to spend their 

time. Animals in these pens can 

also self-regulate the amount of exposure to other animals by moving 

within their pen. Perches should 

be positioned at several levels 

within the living area for climbing and jumping. These perches 

can be constructed of PVC pipe, 

which is impervious to water, 

easily cleaned and not highly 

thermoconductive. Wood perches 

can also be used as long as they are 

replaced once they become excessively soiled or become otherwise deteriorated. As noted previously, flat shelves 

should be avoided due to the potential development of pressure sores on the tail 

of the animal. Large PVC pipe sections can be provided for animals to “hide” 

in, allowing them to break eye contact with other members of their social group 

during aggressive encounters. Finally, certain positions within the pen allow the 

monkeys to view, and be viewed by, other social groups, while other positions 

will greatly restrict the number of other animals the individual can see or be seen 

by.

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Squirrel Monkeys

Animals housed in indoor cages, 

on the other hand, have a limited 

ability to regulate their exposure to 

animals housed in other cages by 

positioning themselves in such a 

way as to limit their ability to view 

other animals. Cage configuration will determine the number of 

monkeys that can be housed. Rack 

caging can be used to house small 

groups, pairs, or single animals. 

These cages should also have perches at varying heights to enable the animals 

to maximize their three-dimensional use of space. The Guide for Care and Use 

of Laboratory Animals (NRC 1996) and the Animal Welfare Regulations (1991) 

provide minimum cage space guidelines and requirements. 

In the laboratory setting, it is best to allow the animals to communicate through 

olfactory, visual, and vocal signals. Even in singly-housed animals, this communication can be preserved by arranging the cages to enable the animals to smell, 

see, and hear each other. Outside noise should be kept to a minimum so that 

the group-housed monkeys can hear each other’s vocalizations. By group-housing animals whenever possible, communication becomes an important form of 

social enrichment. 

Each cage should be provided with swings, moving perches, or objects hanging 

within the cage. These can be made of either a plastic chain, looped PVC tube, 

or other similar materials. Smaller, rack-mounted cages will need to have at least 

one such device, while larger group cages should have two or more, depending on the number of monkeys in the cage. Loose hanging devices should not 

be included in individual cages where the room taken up by the swing would 

limit movement of the animal or where the swing is not appropriate for clinical 

reasons.

Being neotropical primates, squirrel monkeys thrive in warm temperatures. In 

captivity, temperatures should be maintained between 78°-85°F. Relative humidity should be maintained above 50% if possible. If relative humidity falls below 30%, squirrel monkeys can develop crusts around the nostrils and frequent 

sneezing. Special care must be taken in cooler climates to prevent hypothermia.

A plastic chain swing (photo courtesy of C. Abee).
Squirrel Monkeys

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Enrichment

In all caging conditions, a 

number of different food items 

and perch arrangements can be 

used to vary the environment of 

the animals and consequently 

increase activity levels and 

sensory stimulation. Perch 

arrangements with hanging 

objects, such as infant toys and 

practice golf balls, should be 

rotated and replaced routinely. 

Objects must be large enough to prevent swallowing and sturdy enough not 

to be broken into small pieces. Food treats should be nutritious. Fruit and 

vegetables must be selected for quality and should be washed prior to feeding.

Occasionally, squirrel monkeys can experience anxiety when exposed to novel 

stimuli. Care must be taken, particularly with animals in smaller enclosures, 

to ensure that changes are not distressing to the animals. Animals should be 

observed after introduction of new objects to determine whether they show 

signs of fear or avoidance of the object. If this occurs, the object should be 

removed. In larger 

enclosures, this is 

less of an issue, as 

the monkeys can 

move away from 

new objects and 

acclimate slowly.

 

 

An enrichment item that can be manipulated by the 

animals (photo courtesy of C. Abee).

Food items can be suspended, to make them more challenging to consume 

(photo courtesy of C. Abee).
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Squirrel Monkeys

Feeding

The animal’s primary diet should be an appropriate, commercially available diet. 

In addition, each monkey’s diet should be supplemented with fruit and vegetables according to what is seasonally available (although squirrel monkeys can 

have problems with their teeth associated with a high sugar diet; therefore, vegetables are preferred over sweet fruits). Items may include melon, oranges, apples 

(note that there is some evidence that apples may be associated with bloat, a 

frequently fatal disease where the stomach fills with gas), Kiwi fruit, strawberries, pears, bananas, grapes, celery, bell peppers, tomatoes, carrots, and sweet 

potatoes. Additional items, such as various flavors of Gatorade®, multi-vitamins, 

and food-pellet rewards for correct responses may be added for experimental or 

clinical reasons. To encourage foraging, food items can be placed in the cage or 

pen floor after daily cleaning. This encourages the animals to move about the 

cage to select their food. Additional food items can be placed in hanging PVC 

tubes that require the monkeys reach into the tube to find food items.

 

Highly desired food items should be handed out by caregivers at least twice 

daily, for example during daily observations of the animals. This positive interaction with caregivers allows the animals to habituate to the caregivers and allows 

the caregivers to interact in a non-threatening, positive way with the animals.

Sanitation

Standards for the sanitation of caging for squirrel monkeys housed indoors are 

well-described in the National Research Council’s Guide for the Care and Use 

of Laboratory Animals (1996). However, many squirrel monkeys are housed in 

semi-naturalistic environments, where they may be exposed to numerous parasite hosts, such as mollusks, frogs, and small snakes as well as soil and water that 

may have been contaminated by rodents carrying transmissible diseases such as 

leptospirosis. Sanitation programs should include diligent exclusion of slugs, 

snails, frogs, rodents, and as many insects as possible—particularly in tropical environments—to minimize exposure of the animals to these parasite and 

disease hosts.

 

 

 

 

 
Squirrel Monkeys

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10

Special Cases

Age-related Considerations 

If possible, infants and young juveniles should be housed with their mothers 

and remain within their natal social group. Attempts should be made to find 

appropriate foster-mothers for newborn infants that are rejected or orphaned. 

Failing this, or if the newborn is clinically compromised and unable to cling 

normally to a female, it can be housed in a separate nursery. Nursery infants can 

be housed in small, wire-mesh cages. They should be given a cloth surrogate 

mother approximately the same diameter as an adult female monkey to provide 

contact comfort. Infants in the nursery need frequent, positive contact from the 

caregivers as part of the feeding schedule. This contact varies from every hour 

to every four hours depending upon the age of the animal. As the infants grow 

older and strong enough to interact with other infants, they can be moved to a 

larger enclosure with other similarly aged infants. The cage should be equipped 

with multiple levels of perching and swings for the animals to move and jump 

from one to the next. When nursery-reared infants become old enough (6 - 12 

months of age) to eat on their own and move about within a social group with 

adults, they can be introduced into a social group within the general colony.

 

Individual Housing

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A surrogate “mother” for a nursery-reared infant squirrel monkey (photo courtesy of C. Abee).
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11

Squirrel Monkeys

Abnormal social behavior (e.g., over- or under-aggressiveness) that is the result 

of incompatible social partners can result in an individual being removed from 

its current social group to another social group or individual housing for a 

period of time. If the animal is a danger to other animals, a qualified veterinarian 

should determine whether the animal should be placed in an individual cage. In 

addition, individual housing should be considered when animals cannot defend 

themselves from the normal dominance-related aggression that occurs in this 

species and for acute or chronically sick and debilitated animals. 

All individually housed animals should be provided with multiple perches, varied foods, and frequent contact with familiar caregivers. The U.S. Department 

of Agriculture requires that exemptions (e.g., for health or behavioral reasons) 

from social housing must be recorded by the attending veterinarian. In research 

programs, the Institutional Animal Care and Use Committee may exempt 

individual animals from participating in the social enrichment portion of the 

enrichment program when such housing is justified for experimental reasons. 

Every attempt should be made to ensure that there is direct visual, auditory, 

and/or olfactory contact with other squirrel monkeys. Animals that are unable 

to see and hear other squirrel monkeys may be given access to auditory stimuli 

from another room containing squirrel monkeys via a microphone-speaker 

arrangement or a pre-recorded audio tape. Extra contact with familiar caregivers should be provided. In addition to frequent visits, caregivers should provide 

much-desired food treats. Live prey, such as mealworms and crickets, can be 

used to increase the stimuli that food treats can provide. Toys, perches, swings, 

and other hanging devices should be rotated more frequently. Mirrors can also 

be used to provide sensory stimulation.

 

Attempts to socially house squirrel monkeys should be documented for both 

internal tracking purposes and for government regulatory agencies. Some animals that do poorly in large social groups can be housed together with a small 

number of other animals that similarly can not live in large social groups. This 

arrangement will allow social contact with other squirrel monkeys while reducing the level of competition for resources. 
Squirrel Monkeys

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12

Problem Behaviors

Abnormal non-social behavior, including stereotypical movements and self-injurious behaviors, may necessitate a change in housing structures, enrichment 

objects or reinforcement techniques. For example, “pacing” may be eliminated 

by increasing the animal’s available travel paths by installing additional perches. 

Self injurious behavior, such as self hair-pulling and self-biting, often are the 

result of unusual stress. If such behavior is seen in an animal, an evaluation 

should be made of the animal’s current social status and housing environment. 

These animals should also receive a physical examination by a veterinarian to 

determine their health status.

Safety Issues

By far the most effective method for restraining squirrel monkeys is the use of 

leather gloves designed for handling small primates. These gloves provide protection to the human worker while preventing injury to the monkey. As with any 

restraint technique, technicians must be adequately trained to assure that the 

animal is restrained without injuring it. With practice and continued vigilance, 

the use of heavy leather gloves is a safe method of restraint for both the handler 

and the monkey. The use of nets to catch/restrain squirrel monkeys is not recommended. These animals are prone to fractures of the appendages when nets 

are used.

Squirrel monkeys can be trained to jump from cage to cage during rack changes. 

For cleaning of larger enclosures, it is not necessary to remove the animals prior 

to cleaning as long as noxious chemicals are not used and if the animals can 

perch above or away from the area being cleaned.

 

Chemical restraint may be considered by the veterinarian to restrain squirrel 

monkeys for transport and medical care in an attempt to reduce the stress and 

hazards associated with working with these monkeys. Ketamine hydrochloride, 

either with or without xylazine, can be used by the veterinarian for brief sedation. 

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13

Squirrel Monkeys

Squirrel monkeys are wild animals and 

must be treated as such. They can injure 

caregivers through bites and scratches. 

But because they do not carry Cercopithecine herpesvirus 1 (Herpesvirus simiae

or B-virus), a bite or a scratch from a 

squirrel monkey can be treated much 

like the bite from a domestic dog or cat. 

Regardless, care must be taken when 

handling these animals to prevent injury 

to both the caregiver and the animal. 

While it is unlikely that infectious 

diseases would transfer from squirrel 

monkeys to humans, and vice versa, 

common-sense precautions should be 

taken when working with any animal: 

immunocompromised workers should not handle animals with any known illness; masks should be worn when aerosols are present; any worker with an active 

upper respiratory infection should not handle animals; and consultation with a 

health professional may be necessary. Finally, although current human vaccination protocols include vaccination against measles, should an infection occur in 

any individual who resides with the animal caregiver, that caregiver should avoid 

any contact with squirrel monkeys until the infection has resolved. Measles 

spreads rapidly and is fatal in squirrel monkeys.

 

 

References

Abee CR. 1985. Medical care and management of the squirrel monkey. In LA 

Rosenblum and CL Coe, eds., Handbook of squirrel monkey research, 447-488. 

Plenum Press: New York.

Abee CR. 2000. Squirrel monkey (Saimiri spp.) research and resources. ILAR 

Journal 41:2-9.

Brady AG. 2000. Research techniques for the squirrel monkey (Saimiri sp.). 

ILAR Journal 41:10-18.

Use of a leather glove for manual restraint of a 

squirrel monkey (photo courtesy of C. Abee).

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Squirrel Monkeys

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14

DuMond FV. 1968. The squirrel monkey in a seminatural environment. In 

L.A. Rosenblum and R.W. Cooper, eds. The Squirrel Monkey, 31-68. New York: 

Academic Press.

Dunn FL. 1968. The parasites of Saimiri. In L.A. Rosenblum and R.W. Cooper, 

eds. The Squirrel Monkey, 31-68. New York: Academic Press.

Napier JR and Napier PH. 1967. A Handbook of Living Primates. New York: 

Academic Press.

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

Primates. Washington, DC: National Academy Press.

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

Animals. Washington, D.C: National Academy Press. 

Reinhart V (ed). 1997. Comfortable Quarters for Laboratory Animals, 8th edition. 

Washington, DC: Animal Welfare Institute.

Rosenblum LA, Coe CL (eds). 1985. Handbook of Squirrel Monkey Research. 

New York: Plenum Press.

United States Department of Agriculture, Animal and Plant Health Inspection 

Service. 1999. Final Report on Environmental Enhancement to Promote the 

Psychological Well-Being of Nonhuman Primates.

Williams LE, Abee CR, Barnes SR, Ricker RB. 1988. “Cage design and 

configuration for an arboreal species of primate.” Laboratory Animal Science. 

38: 289-291.

 

 

Common Names of Squirrel Monkeys

Saimiri boliviensis: Bolivian squirrel monkey, Peruvian squirrel monkey

S. oerstedii: Grey-crowned Central American squirrel monkey, Black-crowned 

Central American squirrel monkey

S. sciureus: Humboldt’s squirrel monkey, Ecuadorian squirrel monkey, Common 

squirrel monkey, South American squirrel monkey

S. ustus: Bare-eared squirrel monkey, Golden-backed squirrel monkey

S. vanzolinii: Blackish squirrel monkey, Black squirrel monkey, Black-crowned 

squirrel monkey, Black-headed squirrel monkey

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15

Squirrel Monkeys
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. 05-5749

Department of Health and Human Services, 2005

enrichment for nonhuman primates