Polar bears have among the largest home ranges of any mammal; their welfare in zoo settings is fundamentally compromised by the impossibility of replicating their natural ranging needs.
Polar bears in captivity consistently show the highest rates of stereotypic behaviour of any zoo species. Their predatory nature, vast ranging requirements and complex cognitive needs cannot be met in any zoo enclosure. Some welfare scientists argue that polar bear captivity is inherently incompatible with adequate welfare. The conservation education argument for keeping a charismatic Arctic species as climate change proxy is contested — the welfare cost to individual bears is certain while the conservation benefit is debated.