The marine ecosystem incorporates a chain of about 50 calcareous offshore islands and coral reefs in the Lamu Archipelago, running for some 60km parallel to the coastline and adjacent to Dodori and Boni National Reserves on the mainland.
The larger and more sheltered inner islands are covered with tangled thorny vegetation including grass, aloes and creepers. The small outer islands provide nesting sites for migratory seabirds. The reserve conserves valuable coral reefs, sea grass and extensive mangrove forests and is also a refuge for sea turtles and dugongs.
Major wildlife attractions include reptiles such as Sea turtles, Olive ridley, and Reef fish. Lobsters, Sea urchins, Sea star and also frequent sightings in the reserve. It is an important site for wind surfing, diving and snorkelling, water skiing and sunbathing.