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Chole Bay — illustrative image

Chole Bay

Reef 3–18 m Beginner Mafia Island, Tanzania
AI-generated illustration
Documented Also known as: Chole Bay inner reefs
Depth
3–18 m / 10–59 ft
Typical depth
10 m / 33 ft
Visibility
8–20 m / 26–66 ft
Water
25–29 °C / 77–84 °F
Current
Mild
Access
Boat
Best months
Jul–Feb
Recommended cert
Open Water
Typical dive
~55 min

Depth is the range from the top of the site to its usual maximum; "recommended cert" is the mainstream-agency level operators usually ask for, not a legal rule. Currents and visibility change daily — treat everything here as planning ranges.

The sheltered water inside Chole Bay is where Mafia does its quiet, detailed work. Coral gardens rise from seagrass and sand in a patchwork that suits long, shallow dives: ribbontail rays and juvenile fish nurseries in the grass, dense hard-coral heads with anemonefish and sweepers, octopus and lionfish on the rubble edges, and nudibranchs enough to slow any photographer to a crawl. Because the bay is protected from the open swell, it dives in almost any weather — including the windy kusi months when the outer walls are off the menu — and it doubles as the park's training ground and night-dive venue.

The moment you come for: All-weather lagoon diving; seagrass-and-coral mosaic full of juveniles and macro

Topography: Lagoon mosaic of coral gardens, seagrass beds, and sand channels

Current: Sheltered inside the bay; tidal movement is gentle away from the passes.

Know before you splash

Hazards: Shallow coral heads on low spring tides.

Permits & rules: Marine-park daily fee applies.

Conservation: Seagrass is nursery habitat — fins well clear when crossing the shallows.

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