Mafia Island · Tanzania · Wall · Reef
Msumbiji
Sheer little walls from 3 m to 17 m, thick with sponges
Area photo: brittonpaul83 · CC BY-SA 2.0
Msumbiji is a set of rock formations south of Chole Bay, decorated with corals, algae, sponges and anemones. Its slopes and sheer walls begin at around 3 m and fall to a maximum of 17 m, giving short vertical faces to work along within a very forgiving depth range.
Where it is and how deep
7.9619° S, 39.7895° EPublished position for this site.
The dive
The site is a group of rock formations rather than a single reef, and the ground between them alternates between slopes and short sheer walls. Those faces start as shallow as 3 m and drop to a maximum of 17 m, so you can take the vertical sections one at a time, dropping down a face, running its foot, then climbing back up onto the next shoulder without ever committing to a long deep leg.
What covers the rock is the interest here: corals, algae, sponges and anemones grow over the formations, and the sheer sections carry the same encrusting growth as the slopes. Work close in with a torch on the faces, since colour on the sponges goes flat in ambient light even at these depths. The shallow tops at around 3 m make an easy end to the dive, with the safety stop passing over rock rather than in open water.
Marine life and season
The sources we used don't single out particular species here.
| Jan | Feb | Mar | Apr | May | Jun | Jul | Aug | Sep | Oct | Nov | Dec |
|---|---|---|---|---|---|---|---|---|---|---|---|
| Prime | Prime | Fair | Fair | Fair | Good | Good | Good | Good | Prime | Prime | Prime |
Season follows Mafia Island: Whale shark season peaks October-March; the March-May long rains bring rougher seas and reduced visibility.
Questions divers ask
How deep is Msumbiji?+
The slopes and sheer walls start at around 3 m and fall to a maximum of 17 m, which keeps the whole site inside an easy recreational profile.
Sources
- Msumbiji - Scubago — Scubago
More dive sites in Mafia Island
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The north end of an 800 m reefbank, 5 m to sand at 17 m
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Wall
A coral bank to 15 m, dived by day and after dark
Coral garden
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An archway in the rock wall, ringed by reef fish
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A vertical face with shallow caverns, 8 m to 26 m
Reef
Pink and purple corals down a seaward reef slope to 26 m
Channel & pass
The channel through the centre of Chole Bay, dived as a drift
Similar dives elsewhere
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