Are Zoos Really Working for Animals?

Many people like zoos. They see them as places to marvel at rare animals, to educate children, and to support conservation. In fairness, most professionals who work in zoos care deeply about the animals in their care. Over the last two decades, there’s been a steady stream of studies on enrichment, enclosure design, diet, and social grouping — all aiming to improve animal welfare in captivity.

But here’s the problem: even the best zoo is not the wild.

The Missing Benchmark

When we looked across more than two decades of research on large mammals and marsupials in zoos, one pattern stood out. Most studies measure “better” as an improvement within the zoo. For example, giving elephants more space, or adding climbing structures for apes. Almost none compare the welfare of zoo animals to their counterparts in the wild.

That’s not a coincidence. It’s hard to get reliable data from wild populations, and even harder to make direct comparisons. But it also means that the fundamental question:

Who Pays for the Research?

Another pattern is who’s behind the studies. A large share are carried out by zoo organisations, zoo–university partnerships, or bodies such as the European Association of Zoos and Aquaria (EAZA). Independent studies exist, often from NGOs like Born Free or academic teams without zoo ties, but they are far fewer. This doesn’t automatically make zoo-led research biased, but it does shape the questions asked — and the ones avoided.

The Conservation Argument

Zoos often point to their role in supporting conservation in the wild. There’s no doubt that some funding and expertise do reach field projects. But when we trace the numbers, it’s a surprisingly inefficient route: visitor ticket money is filtered through running costs, capital projects, marketing, and administration before a fraction arrives in the field.

A direct donation to a field conservation charity can have a far greater immediate impact.

Good Zoo or Bad Zoo?

At Good Zoo Bad Zoo, we’re building an open, referenced database of all the major English-language studies on large mammals and marsupials in zoos since 2000. We include both supportive and critical perspectives, clearly tagging whether each study uses wild benchmarks, whether it involves animal transfers or herd splits, and who funded it.

Our aim isn’t to cherry-pick the bad stories or ignore the good ones — it’s to give anyone, from casual zoo visitors to policymakers, a clear, evidence-based picture. By bringing pro-zoo and critical studies together in one place, we hope to spark a more honest conversation about what zoos are, and what they’re not.

Please contact us for a full file with links to all the studies we have uncovered.