Nosy Tanikely

Madagascar's most celebrated marine reserve wraps a tiny forested island in a perfect ring of coral that feels almost untouched — turtles rest on every ledge and the reef fish density is among the highest in the western Indian Ocean. The reserve has been protected since 1995 and the results are visible: coral coverage remains extraordinarily high, parrotfish roam in schools too large to count, and hawksbill turtles treat divers as irrelevant background scenery. Shallow gardens give way to a sloping wall that reaches 30 metres through sea fans and antipatharian black coral.