Polar bear welfare in captivity is among the most debated issues in modern zoo ethics. Their extreme space requirements and cognitive complexity make adequate provision exceptionally difficult.
Polar bear welfare represents the most challenging case in zoo animal ethics. The gap between their natural ecological requirements and what even the best zoo can provide is extreme. Stereotypic behaviour occurs in nearly all captive polar bears and indicates profound chronic frustration. Cognitive complexity means that even sophisticated enrichment cannot substitute for the behavioural diversity of wild living. Some prominent zoos including Detroit Zoo have transferred their polar bears to sanctuaries, concluding that adequate welfare cannot be provided. The conservation case for keeping polar bears in zoos is also weak as captive breeding has limited reintroduction potential. This case challenges the fundamental justification for keeping some species in captivity.