Sumbawa is a rarely visited island located east of Lombok and west of Flores and forms part of Nusa Tengara. It is almost cut in half in the middle by a giant bay.

Saleh Bay — a tranquil, island-dotted expanse of blue water harbors one of the country’s most remarkable wildlife encounters: diving and snorkeling with whale sharks. Entering Saleh Bay by ship from the east is spectacular as the bay is semi-enclosed by Mojo island and the peninsula of Tambora. Mt. Tambora, a massive volcano towers over the entrance.

Unlike some whale shark destinations where feeding practices attract the animals artificially, Saleh Bay offers something rare — a natural, unforced interaction with the world’s largest fish. Here, these gentle giants arrive of their own accord, drawn to the fishing platforms that have dotted the bay for generations.

The key to Saleh Bay’s reliability lies in the traditional bagan fishing platforms (see photo on right) used by local fishermen. At night, bright lights lure small fish to the surface. Come morning, the bagans’ catch and leftover baitfish act as an irresistible breakfast buffet for passing whale sharks.

Marine researchers have identified over 100 individual whale sharks in the bay since 2017 — the second-largest documented population in Indonesia after Cenderawasih Bay. Most are juveniles or sub-adult males, many returning to the bay year after year, which suggests the area is an important feeding and growth habitat.

The bagans in Saleh Bay are not easily reached. Best is to visit them as part of a Liveaboard dive trip that passes through the area. Liveaboard trips to the area are infrequent. Plan ahead.