Whale sharks are the world's largest fish and a major ecotourism attraction. Their welfare in wild swim-with encounters and the very few captive settings raises important questions about sustainable wildlife tourism.
Whale shark welfare in tourism is a gradient from better to worse. Non-provisioned encounters at sites where whale sharks aggregate naturally (Ningaloo, Donsol) have a lower impact on behaviour and physiology than provisioned encounters where sharks are conditioned to expect food from tourist boats. Provisioning at Oslob creates chronic dependency, nutritional problems, and dramatically increases boat strike risk - a major welfare concern. Captive whale sharks face the fundamental challenge of accommodating an animal that roams thousands of kilometres in oceanic environments. High historic mortality rates in aquariums reflect the mismatch between natural requirements and even the largest captive facilities. The welfare case for keeping whale sharks in captivity is very weak.