For the first time ever, scientists successfully performed health assessments, including collecting blood and biological samples, taking measurements and attaching satellite tracking tags, to a population of wild whale sharks – the world’s largest fish, classified as “endangered” since 2016. The research advancement, which occurred in Indonesia’s remote Cendrawasih Bay, has significant implications for unlocking the mysteries surrounding the overall health of whale sharks—including the potential impacts of tourism on their health. These details can better inform future conservation policies to protect and encourage their population recovery.