Dive Lembeh Strait
A 15-kilometre volcanic channel in North Sulawesi that defines muck diving - extraordinary biological density built on black sand, holding more rare and bizarre marine life than almost anywhere else on Earth.
Lembeh Strait runs between Lembeh Island and the port of Bitung in North Sulawesi. The seabed is dark volcanic sand - not coral reef - sustained by cold nutrient-rich upwellings from the Indonesian Throughflow. The result is an estimated 1,100 species of marine life, including more than 350 nudibranch species, eight frogfish species, and twelve octopus species - among them the Mimic octopus and Wunderpus, first documented here and most reliably found here.
Diving is slow-paced and close-focus. Muck sites like the Teluk Kembahu bays, Hairball, and Aer Bajo reward patient searching for flamboyant cuttlefish, rhinopias scorpionfish, hairy frogfish, blue-ringed octopuses, and pygmy seahorses. Angel's Window offers a dramatic swim-through pinnacle, Nudi Falls a nudibranch-covered wall, and the Mawali Wreck - a Japanese WWII freighter - a densely colonised large-scale subject.
Lembeh can be dived year-round. July to September brings cold upwellings and peak critter activity. November to February is warmer, less crowded, and equally productive - particularly for nocturnal species.
