Are Zoos Ethical? Arguments for and Against Keeping Animals in Zoos

Zoos, if done right, could be a good thing for the animals and the public—yet many so-called zoos get it terribly wrong.

Polar bear looking over rocky ledge
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A zoo is a place where captive animals are put on display for humans to see. While early zoos (shortened from zoological parks) concentrated on displaying as many unusual creatures as possible—often in small, cramped conditions—the focus of most modern zoos is conservation and education. While zoo advocates and conservationists argue that zoos save endangered species and educate the public, many animal rights activists believe the cost of confining animals outweighs the benefits, and that the violation of the rights of individual animals—even in efforts to fend off extinction—cannot be justified.

A Brief History of Zoos

Humans have kept wild animals for thousands of years. The first efforts to keep wild animals for non-utilitarian uses began about 2500 BCE, when rulers in Mesopotamia, Egypt kept collections in enclosed pens. Modern zoos began to evolve during the 18th century and the Age of Enlightenment, when scientific interest in zoology, as well as the study of animal behavior and anatomy, came to the fore.

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London Zoo's Whipsnade Wild Animal Park (1932) in Dunstable, Bedfordshire. Fox Photos / Getty Images

Early zoos were a dismal affair. Animals were kept in small enclosures with little if any, greenery. With a scant understanding of what the various animals needed, many perished relatively quickly. In accredited U.S. zoos (and elsewhere) things are better now, fortunately. Primates, for example, have gone from barren cages with little furniture to naturalistic and sometimes semi-free-ranging designs. But is it enough?

Arguments for Zoos

  • By bringing people and animals together, zoos educate the public and foster an appreciation of other species.
  • Zoos save endangered species by bringing them into a safe environment, where they are protected from poachers, habitat loss, starvation, and predators.
  • Many zoos have breeding programs for endangered species. In the wild, these individuals might have trouble finding mates and breeding, and species could become extinct.
  • Some zoos have conservation programs around the world that use the zoo's expertise and funding to help protect wildlife against poaching and other threats.
  • Reputable zoos accredited by the Association of Zoos and Aquariums are held to high standards for the treatment of their resident animals. According to AZA, its accreditation guarantees that the organization has undergone strict evaluation by recognized experts to ensure the highest standards of "animal management and care, including living environments, social groupings, health, and nutrition."
  • A good zoo provides an enriched habitat in which the animals are never bored, are well cared for, and have plenty of space.
  • Seeing an animal in person is a much more personal and more memorable experience than seeing that animal in a nature documentary and is more likely to foster an empathetic attitude toward animals.
  • Some zoos help rehabilitate wildlife and take in exotic pets that people no longer want or are no longer able to care for.
  • Both accredited and unaccredited animal exhibitors are regulated by the federal Animal Welfare Act, which establishes standards for animal care.

Arguments Against Zoos

Menagerie of Mr Cross at Exeter Change, London, 1820s
Menagerie of Mr Cross at Exeter Change, London, 1820s. duncan1890 / Getty Images
  • From an animal rights standpoint, humans do not have a right to breed, capture, and confine other animals—even if those species are endangered. Being a member of an endangered species doesn't mean the individual animals should be afforded fewer rights.
  • Animals in captivity suffer from boredom, stress, and confinement. No pen—no matter how humane—or drive-through safari can compare to the freedom of the wild.
  • Intergenerational bonds are broken when individuals are sold or traded to other zoos.
  • Baby animals bring in visitors and money, but this incentive to breed new baby animals leads to overpopulation. Surplus animals are sold not only to other zoos, but also to circuses and hunting facilities. Some zoos simply kill their surplus animals outright.
  • Some captive breeding programs do not release animals back into the wild. The offspring may be forever part of the chain of zoos, circuses, and petting zoos.
  • Removing individual specimens from the wild further endangers the wild population because the remaining individuals will be less genetically diverse and may have greater difficulty finding mates. Maintaining species diversity within captive breeding facilities is also a challenge. 
  • If people want to see wild animals in real life, they can observe wildlife in the wild or visit a sanctuary. (A true sanctuary does not buy, sell, or breed animals, but instead takes in unwanted exotic pets, surplus animals from zoos, or injured wildlife that can no longer survive in the wild.)
  • The federal Animal Welfare Act establishes only the most minimal standards for cage size, shelter, health care, ventilation, fencing, food, and water. For example, enclosures must provide "sufficient space to allow each animal to make normal postural and social adjustments with adequate freedom of movement. Inadequate space may be indicated by evidence of malnutrition, poor condition, debility, stress, or abnormal behavior patterns." Violations often result in a slap on the wrist and the exhibitor is given a deadline to correct the violation. Even a long history of inadequate care and AWA violations, such as the history of Tony the Truck Stop Tiger, does not necessarily ensure abused animals will be freed.
  • Animals sometimes escape their enclosures, endangering themselves as well as people. Likewise, people ignore warnings or accidentally get too close to animals, leading to horrific outcomes. For example, Harambe, a 17-year-old western lowland gorilla, was shot in 2016 when a toddler accidentally fell into his enclosure at the Cincinnati Zoo. While the child survived and was not badly injured, the gorilla was killed outright.
  • Petting zoos have been linked with numerous incidents of diseases including E. coli infection, cryptosporidiosis, salmonellosis, and dermatomycosis (ringworm).

The Last Word on Zoos

In making a case for or against zoos, both sides argue that they're saving animals. Whether or not zoos benefit the animal community, they certainly do make money. As long as there is demand for them, zoos will continue to exist.

Since zoos are likely an inevitability, the best way to move forward is to ensure that zoo conditions are the best possible for the animals that live in captivity and that individuals who violate animal care health and safety sanctions are not only duly punished but denied any future access to animals.

One day we may look back at zoos and marvel at their barbarity. Or, one day we may look back at zoos and be grateful for the species they saved from extinction. Of these two scenarios, only time will tell.

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