Zoos justify keeping animals in captivity partly on educational and conservation grounds — but the welfare cost of captivity must be weighed against these benefits.
The welfare justification for zoo captivity depends on whether conservation and education benefits are real and substantial enough to offset individual welfare costs. Evidence for conservation benefit is stronger for genuine breeding programmes with reintroduction success than for simple captive display. Evidence that zoo visits change visitor conservation behaviour is weaker and more contested. The strongest welfare justification for individual captive animals is when they are specifically ambassadors for species conservation — providing income and awareness that directly funds habitat protection. The welfare of individual animals should always be the primary consideration, with conservation benefit as a secondary justification that must be demonstrated rather than assumed.