Thousands of chimpanzees were used in biomedical research before their retirement. The welfare challenges of these complex, traumatised individuals — and the growing network of sanctuaries providing them refuge — represent one of the most compelling stories in animal welfare.
The welfare of former research chimpanzees reveals the depth and duration of suffering caused by housing a cognitively complex, socially bonded species in isolation and subjecting them to repeated invasive procedures. Chimpanzees understand enough of their situation — they recognise laboratory procedures, veterinary equipment, and the sequence of events that precede painful interventions — that anticipatory fear compounds the pain itself. The psychological damage from years of social deprivation and invasive research is real and long-lasting: some chimpanzees at sanctuaries, decades after leaving research settings, still show fear responses, stereotypies, and social difficulties rooted in their research experience. Sanctuary provides an opportunity for recovery that is genuinely moving to witness — animals that arrived rocking in isolation learning to play, groom, and travel with companions. But recovery is never complete for all individuals, and the welfare debt owed to these animals by the research institutions that used them represents a profound ethical obligation to provide lifelong high-quality care.