Coral Islands - Mafia Island

Hastings Reef’s Coral Gardens are exactly what the name suggests, a sprawling, shallow showcase of hard corals. We always head for the specific entry that drops us right onto the top of the wall, where you’re immediately enveloped by branching staghorn and intricate brain corals. It feels like swimming through an ancient, miniature forest. The true stars here, for us, are the giant clams – some of them are enormous, showing off those vibrant purples and greens. Take your time near the bommies; these are home to the Reef Restoration efforts, and it’s genuinely cool to see the coral trees taking root. You’ll spot a surprising number of spotted hawkfish perched on the coral, watching you with curious eyes, and longfin bannerfish flutter past. We always find a few harlequin tuskfish digging around, their colours really pop against the reef. Visibility here averages 13m, which is good enough to appreciate the scale of the gardens. Because it’s so shallow, maxing out at 13m, it’s a lovely, relaxed dive, perfect for photographers or anyone who just wants to soak up the sheer coral density without worrying about deep stops. Go slow, keep an eye out for pipefish tucked into the crevices, and just enjoy the sun-drenched reef.

Location: Mafia Island, Tanzania, Indian Ocean & East Africa
Coordinates: -7.945100, 39.793500
Type: reef

Marine Protected Area: Mangrove

Best Time to Dive in Mafia Island

The warmest water temperatures in Mafia Island occur in January, averaging 28.8°C. The coolest conditions are in December at 28.8°C.

Monthly Water Temperatures

January: 28.8°C (air: 27.8°C)
February: 28.8°C (air: 28.0°C)
March: 28.8°C (air: 27.8°C)
April: 28.8°C (air: 27.0°C)
May: 28.8°C (air: 26.9°C)
June: 28.8°C (air: 26.0°C)
July: 28.8°C (air: 25.2°C)
August: 28.8°C (air: 25.0°C)
September: 28.8°C (air: 25.3°C)
October: 28.8°C (air: 26.1°C)
November: 28.8°C (air: 27.0°C)
December: 28.8°C (air: 27.7°C)

Nearest Dive Centres to Coral Islands

Marine Life in Mafia Island

Home to 165 recorded species including 94 hard corals, 63 reef fish, 3 sharks & rays, 2 jellyfish, 1 other, 1 whales & dolphins.

Notable Species

Green Turtle (Chelonia mydas)
Allison's Tuna (Thunnus albacares) - Reef Fish
Whale Shark (Rhincodon typus) - Sharks & Rays
Stripy (Katsuwonus pelamis) - Reef Fish
Bigeye tuna (Thunnus obesus) - Reef Fish
Bullet Mackerel (Auxis thazard) - Reef Fish
Tuna (Thunnus alalunga) - Reef Fish
Sperm Whale (Physeter macrocephalus) - Whales & Dolphins
Tail-spot Squirrelfish (Sargocentron caudimaculatum) - Reef Fish
Cauliflower coral (Pocillopora verrucosa) - Hard Corals
Smooth cauliflower coral (Stylophora pistillata) - Hard Corals
Stony coral (Porites cylindrica) - Hard Corals
Stony coral (Porites lutea) - Hard Corals
Larger star coral (Favites pentagona) - Hard Corals
Staghorn coral (Acropora aspera) - Hard Corals
Staghorn coral (Acropora listeri) - Hard Corals
Birdsnest coral (Seriatopora caliendrum) - Hard Corals
Thin birdsnest coral (Seriatopora hystrix) - Hard Corals
Staghorn coral (Acropora polystoma) - Hard Corals
Closed brain coral (Leptoria phrygia) - Hard Corals

Recommended Packing List for Coral Islands

Based on average water temperature of 28.8°C.

Shorty or Rashguard - warm 29°C water needs minimal exposure protection
Mask - essential for every dive
Fins
BCD - buoyancy compensator
Regulator - your most safety-critical piece of gear
Dive Computer - tracks depth, time, and NDL
Surface Marker Buoy (SMB) - essential for boat pickups
Dive Torch - useful for crevices and colour at depth
Underwater Camera - capture your diving memories