A Decade of Tracking Whale Sharks Helps Create a New Marine Park in Indonesia

The whale shark is the largest fish in the ocean — a gentle, spotted giant that can grow longer than a bus and feeds peacefully on tiny plankton and small fish. Yet despite its size, this endangered animal has long been something of a mystery, ranging across vast stretches of ocean that no protected area could ever fully cover. Now a remarkable decade-long study in Indonesia is changing that, turning years of patient tracking into real protection.

Between 2015 and 2025, researchers from Conservation International and the Elasmobranch Institute Indonesia fitted satellite tags to more than 70 whale sharks at sites including Cenderawasih Bay, Kaimana, Saleh Bay off Sumbawa, and the Gulf of Tomini off Sulawesi. The data revealed previously unknown patterns: individual sharks following distinct annual routes, with some traveling toward Papua during tuna spawning and others venturing into the Timor Gap. Crucially, the team also identified a whale shark nursery — a vital clue for protecting the next generation.

“Yet despite its size, this endangered animal has long been something of a mystery, ranging across vast stretches of ocean that no protected area could ever fully cover.”

That science is now translating into action. The Indonesian government is establishing a whale shark–focused marine protected area in Saleh Bay, with zoning that includes no-take zones to shield the nursery habitat, areas for juveniles, and the mangrove ecosystems that sustain the shrimp and plankton the sharks feed on. By protecting not just the animals but the entire food web that supports them, the plan offers a model for how research can be woven directly into conservation policy.

For the fishing communities who share these waters, whale sharks have always been a welcome sight. As scientist Edy Setyawan noted, the animals are seen as a good omen, because their arrival signals that schools of small fish and anchovies are near. Indonesia’s seas hold over 60 percent of the Indo-Pacific whale shark population, making the country’s decisions enormously consequential for the species worldwide. With a decade of data now guiding a new sanctuary, these ocean giants have a far better chance of cruising Indonesian waters for generations to come.