Chole Bay

Kilindoni · Mafia Island · Tanzania

Chole Bay sits on the southeastern coast of Mafia Island, approximately 160 kilometres south of Zanzibar and well off the standard tourist circuit. The bay is the heart of Mafia Island Marine Park, Tanzania's first marine protected area, established in 1995. Covering roughly 50 square kilometres and sheltered by the offshore islands of Chole and Juani, the bay offers protected diving conditions with an astonishing diversity of marine life that has benefited from decades of conservation. The bay's 28 documented dive sites present a range of underwater environments. Kinasi Pass, the most celebrated dive, channels nutrient-rich water through a narrow gap at 26 metres depth, attracting white-tip reef sharks, Napoleon wrasses, large groupers, and dense schools of snapper and barracuda. Chole Wall stretches 800 metres along the bay's eastern edge, draped in soft corals, sponges, and sea fans that provide habitat for nudibranchs, scorpionfish, and camouflaged frogfish. Shallower sites like Chole Reef at 16 metres offer relaxed coral garden dives where green turtles are frequent visitors. Mafia Island's greatest claim to fame is its whale shark population. These gentle giants aggregate in the waters around the island year-round, with the highest concentrations between October and February when plankton blooms attract dozens of individuals. Most whale shark encounters happen via snorkelling at the surface, as the sharks feed in shallow water, but the knowledge that the largest fish in the ocean are swimming just above while you explore the reef below adds an incomparable dimension to every dive. With over 50 species of coral and 400 species of fish recorded in the marine park, Chole Bay delivers reef diving quality on par with more famous Indian Ocean destinations, but with a fraction of the divers. Visibility ranges from 10 to 25 metres depending on tidal conditions, and water temperatures remain a comfortable 25 to 29 degrees Celsius. The island's limited infrastructure means smaller group sizes and a more intimate diving experience, making Mafia one of East Africa's best-kept underwater secrets.