Zoos aren’t for animals. They’re for us.

A family of giraffes at the Bronx Zoo in New York City feed in their indoor enclosure on February 18, 2018. | Andrew Lichtenstein/Corbis via Getty Images

Zoos say they’re leaders in protecting wildlife. But is it true?

This week, a leading wildlife conservation group declared that zoos play an essential role in protecting wild species from extinction.

“Zoos, aquariums and botanic gardens are critical conservation partners, and their role should not be under-valued, under-recognized or misunderstood,” the International Union for Conservation of Nature (IUCN), a nonprofit that’s assessed extinction threat levels for more than 150,000 species, announced in a new position statement. “For anyone who questions the value of zoos in the modern age, IUCN’s position is clear — zoos are essential.”

It’s a bold statement from an authoritative voice on wildlife protection, but is it true? An examination of how zoos spend their money suggests that, despite branding themselves as champions of conservation, they devote far more resources to their main, original prerogative: confining animals for entertainment and profit.

“The way that zoos have been trying to justify their existence for quite a few years now is pointing to conservation,” said Delcianna Winders, director of the Animal Law and Policy Institute at Vermont Law and Graduate School. “But the reality is that it’s really a very small fraction of their funding that is going to field conservation.” (Disclosure: This summer, I attended a media fellowship program at Vermont Law and Graduate School.)

In 2022, most of the 238 zoos and aquariums accredited by the nonprofit Association of Zoos and Aquariums (AZA) spent a collective $252 million on field conservation — efforts to protect and preserve wildlife habitats. That’s serious money for the broader conservation movement.

“That puts them collectively among the world’s largest contributors to conservation,” Daniel Ashe, president and CEO of the AZA, told Vox. However, it’s just 5 percent of how much zoos and aquariums spent on operations and construction alone in 2018.

Similarly, an analysis of scientific papers published by AZA member institutions from 1993 to 2013 found that only 7 percent were related to biodiversity conservation.

Zoos argue that in addition to their conservation efforts in the field, their very existence contributes to species conservation. By breeding animals in captivity, and preserving their genetic material in “biobanks,” the argument goes, they’ve created a stock of animals — known as “insurance populations” — who could be released back into nature if wild populations dwindle to alarming levels.

Emma Marris, an environmental writer and author of Wild Souls: Freedom and Flourishing in the Non-Human World, wrote in a 2021 New York Times opinion piece that it’s “as if they might be called upon at any moment to release them, like Noah throwing open the doors to the ark, into a waiting wild habitat. But that day of release never quite seems to come.”

“I’m very skeptical that a lot of these captive breeding programs have any practical relevance to conserving species in their natural habitat, which, in my view, is the point of conservation,” said Mickey Pardo, a behavioral ecologist and postdoctoral research fellow at Colorado State University who studies elephants in the wild. The reason, Pardo says, is because reintroduction stemming from captive breeding programs is incredibly challenging and thus rare, and it’s not the primary goal of most captive breeding programs to begin with.

There are some exceptions, Marris notes, in which zoos have played a starring role in reintroducing threatened and endangered species to the wild, including the California condor, the Arabian oryx, and Black-footed ferrets, among others. Ashe told me zoos have played a role in dozens and dozens of reintroduction programs, though he didn’t have a specific number. It’s important work and should be celebrated, as should zoos’ contributions to field conservation. But, Pardo says, it doesn’t justify AZA-accredited zoos and aquariums keeping wild animals in captivity who are not part of any current reintroduction program nor likely to become part of one in the future.

Currently, AZA-accredited zoos and aquariums have about 780,000 animals.

Andrew Lichtenstein/Corbis via Getty Images
A Louisiana pine snake sits in an enclosure at the Memphis, Tennessee zoo in 2019. The snake is North America’s rarest, and on the verge of extinction because of habitat loss in Louisiana and East Texas. The Memphis Zoo is attempting to breed the species in captivity and reintroduce it to the wild in an effort to save it from extinction.

Kira Mileham, IUCN’s global director of strategic partnerships, disagrees with the argument that field conservation is all that matters. Mileham told Vox captive breeding programs at zoos do more than just create insurance populations, and that they contribute to field conservation by providing opportunities for researchers to learn about species’ behavior, nutrition, veterinary needs, and more. Mileham added that zoos also play an important role in temporary rescue and “head start” efforts by, say, taking animals and/or their eggs that are facing a serious, temporary threat out of the wild, and then returning them when it’s safe.

Zoos undeniably do some good work for species conservation; however, that work can obscure their dark side: the suffering of animals in captivity.

Life at the zoo

Animals who, in their natural habitats, would travel great distances are resigned to living in film-set versions of lush rainforests and vast savannas while surrounded by city noise. As a result of the lack of stimulation and small environments, some animals will develop “stereotypic” behavior, in which they engage in repetitive motions that are rare in the wild.

Researchers call it “zoochosis,” a play on “psychosis,” though making enclosures a little nicer and providing “enrichment activities” to animals both help, as do pharmaceutical drugs.

There was Gus, the Central Park Zoo polar bear who would swim figure eights in his pool for sometimes up to 12 hours a day (his enclosure was just 0.00009 percent of his range in the wild), and Sukari, the giraffe at Roger Williams Park Zoo in Providence, Rhode Island, who for hours would lick steel cables, walls, and gates. Other animals pace, rock back and forth, and head-bob, or engage in self-harm, like pulling out their hair or biting themselves. There are many stories of escape attempts.

Despite it all, AZA-accredited zoos keep acquiring more animals, either from other zoos, breeding them on their own, taking them from the wild (how 80 percent of animals at AZA-accredited aquariums are acquired, Ashe told me), as rescues, or from a number of other sources, such as private breeders and hunting ranches.

Mileham refutes the notion that many zoos are just acquiring animals at the expense of their welfare, however: “I don’t think [leading zoos] kind of flippantly trade off the welfare of species for the sake of having them in their facilities,” she said. And not every welfare matter is black and white, Mileham said. For instance, some animals in zoos might have come from areas with high levels of conflict with humans. “We can’t pretend that an animal in the wild always has a perfect life and has no welfare compromises just because they happen to not be in human care.”

Ashe assured me that “when you see animals at AZA member institutions, you’re seeing animals that are thriving there.” He went on to say, “I understand some people just don’t like the idea of any animal in a state of confinement, and in those cases, we just have a fundamental disagreement.”

When Marris asked Ashe about the constraints of captivity, Ashe largely shrugged the problem away, saying that, well, everyone has constraints put on them: “We are all captive in some regards to social and ethical and religious and other constraints on our life and our activities.”

I asked Ashe about this quote, and he said, “It’s factually true — we all live with constraint in our social life and we agree to constraint so we have social order.” He’s right, of course, that it’s true for humans, but there’s a glaring omission in his response: Animals can’t agree to the constraints we impose on them.

I can’t think of a more dissatisfying answer to the ethical dilemma of putting hundreds of thousands of wild animals behind glass. But it does reveal that the ideology undergirding earlier zoos and aquariums largely persists today — that animals are here for us, not with us.

Zoos: What are they good for?

Zoos justify their existence not just through conservation, but also by their educational work. Their actual impact in that domain, however, is likely minor.

The AZA says one of the “superpowers” of its 238 accredited zoos and aquariums is that they have “the opportunity to influence and inspire the 200 million people who visit every year.” On its face, it makes sense: If everyone could just see the beauty of the animal kingdom up close and learn about the plight of threatened species, they might be inspired to support or get involved in conservation work. Surely, zoos have that effect on some, but there’s no evidence it’s the case for many.

On the contrary, most people don’t read the educational plaques at zoos, and according to polls of zoo-goers, most go to spend time with friends or family — to enjoy themselves and be entertained, not to learn about animals and their needs. One study found the level of environmental concern reported by attendees before they entered the zoo was similar to those who were polled at the exits.

While the educational value of zoos is dubious, there’s certainly one message zoo-goers receive, if only implicitly: That it’s perfectly fine, even good, to put wild animals on display in tiny enclosures for the public’s leisure. In other words, animals — even if they’re suffering right in front of us — can be objects of entertainment.

“It’s rooted in this notion that yes, we have this privileged right to observe these animals at any cost to [them] or to their species more generally, and it’s deeply troubling,” Winders said.

The idea that we must exploit some animals in order to protect others creates a bizarre false choice, even when there are much more humane paths taken by others in the wildlife protection movement, like animal sanctuaries.

What a more humane zoo could look like

Animal sanctuaries are like zoos in that they’re large properties where animals live in captivity, but they differ in every other way. For one, animals in sanctuaries tend to have far more space than animals in zoos, and they’re there to live on their own terms, not to be put on display for an entrance fee. Some sanctuaries are not open to the public, while others conduct small tours or have much smaller attendance numbers than the typical zoo. (Beware, however, that many operations call themselves sanctuaries but in reality are more like petting zoos.)

The Wild Animal Sanctuary, a 45-minute drive from Denver, Colorado, provides a compelling example of how animals can better coexist with visitors. The 1,214-acre operation, home to rescued bears, tigers, lions, wolves, and other species, was closed to the public for its first 20 years. But in the early 2000s, it began to open up to visitors, who can only see the animals from the sanctuary’s observation decks and more than 1.5 miles of elevated walkways, causing less disturbance than zoo-goers.

The Wild Animal Sanctuary
Visitors at the Wild Animal Sanctuary in Keenesburg, Colorado, watch a bear from high up on the sanctuary’s elevated walkways.

Animals typically wind up in sanctuaries — the ethical kind, at least — because they were abandoned or injured, rather than bred, purchased, or taken from the wild. The Global Federation of Animal Sanctuaries, the animal sanctuary world’s equivalent to the Association of Zoos and Aquariums, takes the position that captive breeding is only permitted if it’s done for eventual reintroduction into the wild — unlike zoos, which largely breed animals as insurance populations and to keep a steady supply to put on display.

Some critics have called for zoos to phase out keeping animals from species that aren’t either critically endangered or extinct in the wild, or for which there’s no viable reintroduction program. Additionally, they argue, urban zoos should either close down or set limits on how many animals they keep.

I would add one more thing that zoos — and sanctuaries, for that matter — could do: Stop serving meat and dairy in their cafeterias. There’s the painfully obvious point that an institution whose mission is to protect animals probably shouldn’t sell animal meat. But there’s also this: One-third of Earth’s habitable land is devoted to cattle grazing and growing corn and soy to feed farmed animals, which has resulted in mass habitat loss for wildlife and crashing biodiversity levels. Meat production is the leading cause of global deforestation, and thus the leading threat to wildlife habitats.

Reforming zoos won’t be easy, and arguably, a lot of conservation dollars might vanish if zoos looked different. But it says something about the conservation movement, and us, if one of the best ways to raise funds for wild animals is to put them in captivity. I don’t have the answers for how the conservation movement could supercharge its funding in lieu of the significant amount of funding zoos provide, but I think it’s clear, as Marris puts it, that zoos are not worth the moral cost.

As our understanding of animal sentience and their capacity for suffering has grown, our economy has slowly adapted. Fashion designers are replacing leather and fur with animal-free textiles, meat companies are now selling plant-based nuggets and burgers, and in 2018, the traveling circus Ringling Bros. and Barnum & Bailey announced it would stop using animals, such as lions, tigers, and bears, in its shows. Zoos, too, could reinvent themselves for a more enlightened age by focusing on what animals need, not what the public wants to do on a Saturday afternoon.