Can't stop, won't stop: is stereotypy a reliable animal welfare indicator?

Mason and Latham examined whether stereotypic behaviour is a trustworthy welfare marker. Reviewing many studies, they showed that while stereotypies often correlate with poor conditions at the group level, individuals that stereotype are not always the most stressed; some pacing animals may even be coping better than non-pacing pen-mates that have shut down. Because established stereotypies can persist after conditions improve, their frequency can mislead. The authors recommended treating stereotypy as a 'red flag' demanding investigation rather than a direct dial of suffering, and combining it with physiological and other behavioural measures. The paper strongly influenced how felid welfare assessments interpret pacing, warning against using its mere presence to certify good or bad welfare.