Proboscis monkeys are Endangered Bornean primates whose extreme dietary and social specialisations make them almost impossible to maintain in captivity, concentrating welfare efforts on wild population protection.
Proboscis monkey welfare in captivity is exceptionally challenging — their specialised digestive system cannot be adequately replicated in captive settings. The inability to feed them their natural diet without causing fatal bloat means captive individuals face chronic dietary compromise. This species represents a case where welfare concerns strongly favour keeping the population wild rather than investing in captive breeding programs that cause suffering. Conservation efforts should therefore focus overwhelmingly on protecting Bornean riverine and mangrove habitat, reducing hunting, and controlling deforestation. The few captive individuals held in educational facilities require access to appropriate foliage, water for swimming, and complex social groups to minimise welfare harm.