AVMA Animal Welfare Division Director's Testimony on the Captive Primate Safety Act


Gail Golab, PhD, DVM
Director, Animal Welfare Division
American Veterinary Medical Association

Captive Primate Safety Act
(H.R. 2964)

Before the
House of Representatives Committee on Natural Resources
Subcommittee on Fisheries, Wildlife and Oceans

March 11, 2008

View PDF version

Thank you, Madam Chairperson and members of the Subcommittee, for giving the American Veterinary Medical Association the opportunity to speak in support of the Captive Primate Safety Act, H.R. 2964.

I am Dr. Gail Golab, Director of the American Veterinary Medical Association's Animal Welfare Division. The AVMA represents more than 76,000 U.S. veterinarians engaged in every aspect of veterinary medicine and public health. Among other things, our members protect the health and welfare of our nation's animals, help conserve endangered species, and protect animal and human health through prevention and control of zoonotic diseases. Nearly 600 of our members work with wildlife in natural or zoologic settings, 1,000 of our members work in biomedical research, and 300 spend at least 50% of their time working with exotic pets. Within these environments, we have approximately 170 members who work with or come into contact with nonhuman primates on a regular basis. Other veterinarians work at federal agencies, such as the National Institutes of Health or the Centers for Disease Control and Prevention, where they deal with the implications of diseases affecting human health that originate in nonhuman primates.

As a preface to our testimony, I emphasize that arguments presented by the AVMA herein are applicable only to the private ownership of nonhuman primates by unlicensed individuals. The AVMA fully supports animal health professionals who work with nonhuman primates in conservation and biomedical research efforts. As you can imagine, it is one thing to work with these animals in settings in which there are appropriate enclosures and trained personnel and quite another when they are kept in the backyard or living room of an unqualified individual. The data support this belief: according to the Captive Wild Animal Protection Coalition,1 more than 80% of health and behavioral issues with nonhuman primates arise from those that are kept as pets.

AVMA policy, based on considerable research and deliberation, supports limiting or prohibiting private ownership of indigenous and non-native wild animals that pose a substantial risk to public health, domestic animal health, or the ecosystem, or whose welfare is unacceptably compromised.2 The AVMA thereby supports related regulatory efforts to limit or prohibit private ownership, and importation for the purpose of private ownership, of such indigenous and non-native wild animals. Because nonhuman primates pose significant risks to the health of the public and domestic animals — including the possibility of severe injury to the humans and domestic animals with which they come in contact — the AVMA opposes private ownership of these animals. Furthermore, the AVMA also does not support the use of nonhuman primates as assistance or service animals because of animal welfare concerns, the potential for serious injury, and zoonotic risks.3 Risks of human injury and zoonotic disease are often greatest in the very populations such animals serve.

The risks posed to and by nonhuman primates maintained by private individuals fall into four broad categories: inadequate husbandry, physical injury to humans and other domestic animals, disease transmission, and ecosystem concerns. Precise numbers are difficult to elucidate, but Born Free USA and the Captive Wild Animal Protection Coalition estimate4 that more than 15,000 nonhuman primates are owned by private individuals in the United States today. Raising and training these animals is complex, and most private owners are inexperienced in meeting related challenges. Privately owned nonhuman primates have attacked humans and other animals, and they have escaped from their cages to roam freely in communities.5

Nonhuman primates are highly intelligent and social animals that present unique husbandry challenges. Most captive environments cannot meet the complex physical and behavioral needs of these species. Monkeys need large, secure enclosures and specialized diets, and they must be provided with a variety of ever-changing toys and exercise equipment to keep them challenged and stimulated.6 If multiple nonhuman primates are kept, consideration must be given to providing sufficient numbers of food and water stations, an adequate number and appropriate type of nest boxes, and visual barriers that prevent direct eye contact with dominant animals. Sanitation can become a significant issue because monkeys are not easily housebroken and will often remove diapers that are applied in an effort to control excreta.7 It can also be difficult to identify veterinarians who are not only qualified, but willing to care for nonhuman primates kept as pets. As one board-certified zoo veterinarian told us, "I am very comfortable working with primates in zoo and laboratory settings, but I refuse to work with primates in private practice settings because of concerns for the safety of my staff and myself due to bites and disease."

To create suitable pets, baby primates may be taken away from their mothers when only hours or days old. Evolved to have continual body contact with their moms, infant primates will cling to towels or stuffed animals as substitutes, and both mothers and infants often exhibit signs of depression as a result of forced separation.8-10 Infant females taken away from their mothers don't develop the parental skills necessary to raise their own young, and this initiates a vicious cycle of rejected infants that must be raised by people to physically survive.11 When young, nonhuman primates are dependent on their natural mother or a surrogate human and are generally cooperative; however, as they reach sexual maturity, their behavior becomes more unpredictable and aggressive.12 The response of the private owner to changed behavior may be to reduce contact with the nonhuman primate. In addition, nonhuman primates can be very destructive in home environments and will shred furniture, curtains, clothes, and other personal belongings; turn on faucets; and unlock and open doors.13 A typical private owner's response to this behavior is more restrictive confinement. The isolation resulting from both owner behaviors directly conflicts with the psychological needs of most nonhuman primates, which tend to live in social groups.14

Given good care and proper nutrition, nonhuman primates have long lifespans. Twenty-five to 30 years is not unusual for smaller species, while macaques, baboons, and spider monkeys can reach 40 years old, and apes 55. Many private owners are not able to make a life-long commitment to common domestic pets, let alone a pet as challenging as a nonhuman primate. Zoos don't have the space for nonhuman primates that were formerly pets, and sanctuaries are overburdened.12 Furthermore, once a nonhuman primate has been hand-raised to adulthood by people, it can be difficult or impossible to reintroduce it into a peer group.15, 16 If an introduction can be accomplished without the former pet being harassed, intimidated or attacked, the nonhuman primate may still remain a social outcast. Neurotic behavior and depression can be the consequences of such alienation.

Make no mistake about it, nonhuman primates kept as pets — while cute, cuddly, and often very entertaining — can also pose serious injury risks for their human caretakers and other domestic animals. Infant primates may seem adorable, but as they grow larger, they become stronger and more aggressive. Many nonhuman primates exhibit unpredictable behavior as they mature; males can become aggressive, and both males and females will strike, scratch, and bite to defend themselves and establish their place in the hierarchy of their peer group or surrogate human family.17 Reviews of bite injuries inflicted to humans by nonhuman primates indicate that severe lacerations, wound infections, and permanent complications (e.g., muscle contractures, osteomyelitis) resulted in 33% of cases.18,19 Nonhuman primates are proportionately much stronger than human beings, and as a result, the risk of unintentional injury is high.

The Captive Wild Animal Protection Coalition reported that between January 1, 1995 and January 1, 2005 there were 132 incidents of human injury caused by captive primates or escapes by captive primates in the United States.5 More incidents may have occurred but not been reported. Deprived of social relationships with other nonhuman primates (as often happens when nonhuman primates are kept as pets), it is not unusual for nonhuman primates to become highly bonded to their owners. They may attack unfamiliar individuals,17 and in fact, most injuries occur when nonhuman primates have contact with people other than their owners or trained caretakers. Although many nonhuman primates are purchased from licensed breeders or brokers, some nonhuman primates acquired as pets are purchased over the Internet or during weekend events. The probability of contact with unfamiliar and untrained individuals increases during such activities and during associated interstate transport.

In addition to inadequate husbandry concerns and human and domestic animal injury risks, nonhuman primates can and do spread viral, bacterial, fungal, and parasitic diseases. Each species of nonhuman primate has the capacity to introduce or spread illnesses that threaten human and domestic animal heath. Transmission of zoonotic disease is, of course, bidirectional and nonhuman primates are highly susceptible to some common human viral, bacterial, and fungal pathogens. An example is transmission of herpes simplex virus to marmosets as a result of private owners kissing or breathing on their nonhuman primate pets. Although herpes simplex infections in humans may cause disease as mild as a cold sore, in marmosets exposure to the virus can result in acute disseminated disease with neurologic involvement and a high fatality rate.20

Like humans, all of the more than more than 240 species of extant nonhuman primates are susceptible to bacterial infections, including tuberculosis, salmonellosis, shigellosis, and campylobacter.21 Tuberculosis is especially common among macaques22 and their owners. New world monkeys (mostly frugivores) are prime candidates for infection with water-borne, gram-negative bacteria, such as klebsiella.21 Primates infected with klebsiella pose a special danger to human infants and children with mild respiratory infections.

Nonhuman primates also carry viruses, such as Herpes B, Simian Immunodeficiency Virus (SIV), polio, yellow fever, and poxviruses (including monkeypox and chickenpox) that can be passed to other nonhuman primates and to people. Herpes B virus, which is subject to both bite and airborne transmission, is highly prevalent (80-90%)23 in adult macaques and can cause a potentially fatal meningoencephalitis in people. The Marburg virus affects both nonhuman primates and people, and causes a hemorrhagic fever, which is rare, but fatal in 23-25% of human cases;24 case fatality rates in nonhuman primates are up to 100%. Although the Marburg virus is indigenous to Africa, a healthy black market trade in nonhuman primates25 creates an ever-present risk of importation into the United States. New world monkeys can carry and acquire the measles virus,26 which is easily contracted and transmitted by young children and the elderly. All four poxviruses are found in new world monkeys, with monkeypox being the most frequent.21 Viral hepatitis A is common in capuchins, owl monkeys, and tamarins. Often undetectable in these monkeys, the disease can still be passed to humans and primate handlers often contract this virus from recently shipped animals.21 In addition, live rabies vaccines that are manufactured for dogs and cats, and sometimes inappropriately administered to nonhuman primates, can cause rabies in old world monkeys, which can then be spread to humans.21

Nonhuman primates and people share fungal and parasitic diseases as well.27 Although not common, fungal diseases of potential concern include streptothricosis (a skin infection), candidiasis (an infection of the mucous membranes), and ringworm. Many primates harbor parasites that are easily transmitted to people, including protozoa, nematodes (elongated cylindrical worms), tapeworms, and arthropods (lice, mites, and fleas). Giardia, a protozoan parasite that reproduces in the small intestine, can cause recurrent diarrhea in both nonhuman primates and people, although clinical signs are often not apparent in the former.28 Amebiasis, a disease caused by another zoonotic protozoan parasite, may result in no clinical signs or protracted diarrhea from chronic colitis and, occasionally, abscesses in the brain, liver, and/or lungs.21

Finally, keeping of nonhuman primates by private individuals presents ecologic risks. Nonhuman primates that are intentionally released into the wild or that unintentionally escape from their human caretakers may naturalize, particularly in warm, southern states. Once established, these nonhuman primates have the potential to become reservoirs of disease (e.g., yellow fever), may contaminate water supplies, present risks of injury for humans and domestic animals (e.g., livestock, pets), and may destroy private and public property, including crops cultivated for human consumption.

As described in our testimony, nonhuman primates maintained by private individuals pose serious husbandry, physical injury, disease-transmission, and ecologic risks. Although importing nonhuman primates to the United States for the pet trade has been banned by federal regulation since 1975 and many states already prohibit keeping these animals as pets, a vigorous trade in these animals remains. Federal legislation is needed because many of these animals move via interstate commerce.

This bipartisan bill amends the Lacey Act to prohibit transporting monkeys, great apes, lemurs, and other nonhuman primates across state lines, much like the Captive Wildlife Safety Act, passed unanimously in 2003, did for tigers and other big cats. This bill has no impact on trade or transport of animals for zoos, medical and other licensed research facilities, veterinarians, or certain other licensed and regulated entities. As such, the AVMA supports this legislation and looks forward to continue working with members of Congress on its behalf.

Thank you for the opportunity to appear before you today and speak on behalf of this important legislation.

1 153 Cong Rec S13520 (2007)

2American Veterinary Medical Association. Private ownership of wild animals. Available at: www.avma.org/issues/policy/wild_animal_ownership.asp. Accessed March 5, 2008.

3American Veterinary Medical Association. Nonhuman primates as assistance animals. Available at: www.avma.org/issues/policy/nonhuman_primates.asp. Accessed March 5, 2008.

4Captive Wild Animal Protection Coalition. Congress urged to move swiftly on bill to protect primates. Available at: www.cwapc.org/pr/pr_20050316_PrimateBill.html. Accessed March 5, 2008.

5Captive Wild Animal Protection Coalition. Primate incidents 1995-2005. Available at: www.cwapc.org/pr/download/PrimateIncidents1995-2005.pdf. Accessed March 5, 2008.

6University of Missouri Office of Animal Resources. Environmental enrichment. Available at: oar.missouri.edu/OAR_WEB$/osop/sopDocs/Environmental_enrichment/General_Environmental_Enrichment.doc. Accessed March 5, 2008.

7University of Wisconsin-Madison Veterinary Medical Teaching Hospital. Do monkeys make good pets? Available at: vmthpub.vetmed.wisc.edu/sa_services/special_species/faq.htm. Accessed March 5, 2008.

8Willner P. The validity of models of animal models of depression. Psychopharmacology 1984;83(1):1-16.

9Hoff MP, Nadler RD, Hoff KT, et al. Separation and depression in infant gorillas. Developmental Psychobiology 1994;27:439-452.

10Kaufman IC, Rosenblum LA. The reaction to separation in infant monkeys: anaclitic depression and conservation-withdrawal. Psychosomatic Medicine 1967;29:648-675.

11Harlow HF, Harlow MK, Dodsworth RO, et al. Maternal behavior of rhesus monkeys deprived of mothering and peer associations in infancy. Proceedings of the American Philosophical Society 1966;110(1):58.

12Porton I, Carter S, Beck B, et al. Bedtime for Bonzo: the real bedtime story. Available at: http://www.orangutanssp.org/bedtime-for-bonzo/. Accessed March 5, 2008.

13Primate Info Net. Are you sure you want a monkey? (reprinted from Monkey Matters Magazine). Available at: pin.primate.wisc.edu/aboutp/pets/areyousure.html. Accessed March 5, 2008.

14Anthropology Program, Department of Behavioral Sciences, Palomar College, California. Social structure. Available at: anthro.palomar.edu/behavior/behave_2.htm. Accessed March 5, 2008.

15Meder A. Integration of hand-reared gorillas into breeding groups. Zoo Biology 1990;9:157-164.

16Inglett BJ, French JA, Simmons LG, et al. Dynamics of intrafamily aggression and social reintegration in lion tamarins. Zoo Biology 2005;8:67-78.

17Hevesi R. Welfare and health implications for primates kept as pets. In: Born to be wild: primates are not pets. International Fund for Animal Welfare. Available at: www.ifaw.org/ifaw/dfiles/file_553.pdf. Accessed March 5, 2008.

18Goldstein EJC, Pryor EP, Citron DM. Simian bites and bacterial infection. Clin Infect Dis 1995;20:1551-1552.

19Janda DH, Ringler DH, Hilliard JK, et al. Nonhuman primate bites. J Orthop Res 1990;8:146-150.

20Lefaux B, Duprez R, Tanguy M, et al. Nonhuman primates might be highly susceptible to cross-species infectivity by human alpha-herpesviruses. Vet Pathol 2004;41(3):302-304.

21Renquist DM, Whitney RA. Zoonoses acquired from pet primates. Vet Clin North Am: Sm Anim Pract 1987;17(1):219-240.

22Willis J, Webb JL, LeRoy BE, et al. An overview of tuberculosis in macaques. Available at: www.vet.uga.edu/vpp/clerk/willis/index.php. Accessed March 5, 2008.

23Ostrowski SR, Leslie MJ, Parrott T, et al. B-virus from pet macaque monkeys: an emerging threat in the United States? Emerg Inf Dis 1998;4(1):117-121.

24Centers for Disease Control and Prevention. Marburg hemorrhagic fever fact sheet. Available at: www.cdc.gov/ncidod/dvrd/spb/mnpages/dispages/marburg/qa.htm. Accessed March 5, 2008.

25Webster D. The looting and smuggling and fencing and hoarding of impossibly precious, feathered and scaly wild things: inside the $10 billion balck market in endangered animals. The New York Times Magazine 1997;Feb 16: 27-33, 48-50.

26Institute for Laboratory Animal Research. The psychological well-being of nonhuman primates. Washington, DC: National Academies Press, 1998; 89.

27Baskin G. Pathology of nonhuman primates. Available at:  http://www.primate.wisc.edu/pin/pola6-99.html. Accessed March 5, 2008.

28Division of Veterinary Medicine, Walter Reed Army Institute. Significant zoonotic disease of non-human primates. Available at: netvet.wustl.edu/species/primates/primzoon.txt. Accessed March 5, 2008.