Diving on Mafia Island: a complete guide
Mafia Island, located south of Zanzibar, is a wonderful diving destination in Tanzania. Surrounded by a protected marine reserve, the island offers divers the chance to explore some of the country’s most pristine coral reefs. The reefs around Mafia Island are home to a wide range of marine life, including sharks, rays, turtles, seahorses and numerous species of tropical fish. And it’s also a good place to spot whale sharks!
And in case you were wondering, the island has nothing to do with the mafia. The name “Mafia” is derived from the Arabic morfiyeh, meaning “group” or “archipelago,” or from the Swahili mahali pa afya, meaning “a healthy dwelling place.”
Table of contents
Why dive on Mafia?
Compared to the better-known and quieter Zanzibar, the dives on Mafia Island are a lot more challenging. This is mainly due to the strong tides and currents that occur in this area, especially in and around the Mafia Island Marine Park. This makes it an excellent destination for drift diving – where you let the current carry you along the reef.
The currents bring lots of nutrients, which makes for richer and more active marine life. Consequently, the chances of spotting large marine life here are considerably higher than around Zanzibar. Think reef sharks, large schools of barracudas, tuna and even whale sharks (especially between October and February). Because of the conditions, this area is especially suitable for divers with some experience, or those looking for more excitement and variety underwater.
Mafia is less touristy than Zanzibar and still feels authentic and unspoiled. No crowded beaches or crowds of boats,but small scale, tranquility and nature. In addition, Mafia offers some of the best macro diving in East Africa: nudibranchs, ghost whistle fish, seahorses and colorful shrimp are regularly spotted here.
Best travel time for diving on Mafia
Diving on Mafia Island can be done year-round, but conditions vary greatly by season. The best period is from October to March, when visibility is good, the water remains calm and the chances of seeing whale sharks are greatest. During the rainy periods (especially April and May), visibility is lower and some dive centers are even closed.
Visibility
Visibility is usually between 10 and 30 meters, especially in the dry season. In the rainy season, visibility can drop to 10 meters or less, depending on the dive site and currents.
Water temperature
The water is warm, with temperatures between 25°C and 29°C. In the cooler months (July-September), it may drop slightly.
Current
Often strong, ideal for drift diving (especially at spring tides). Diving at Mafia thus depends heavily on the tide. The bay does allow you to dive without strong storm surge. The diving school always watches the tide and only takes you into the water when conditions are good and safe.
| Period | Diving conditions | Wetsuit Advice | Details |
|---|---|---|---|
| October – February | Best visibility (20-30 m), warm water, calm sea | 3 mm or shorty | Whale shark season, lots of life, good for drift diving |
| March – May | Visibility diminishes, sea rougher, chance of rain | 3 mm full | Rainy season; some dive centers close temporarily |
| June – September | Less stable conditions, moderate visibility (10-15 m) | 3 mm full | Windy season; fewer divers, cooler nights |
Best dive sites on Mafia
Actually, on Mafia you dive in 3 different locations, all of which of course have different dive sites as well. Diving here is highly dependent on the different tides, so it requires tighter planning and so where and what time you go diving may vary from day to day.
Diving from the shore
Dive into the world of the strange and the wonderful. You may see seahorses, frogfish, nudibranchs, shrimp, crabs and more small stuff that you will probably look up in a fish id booklet after the dive. In short, it’s all about muck diving, which means keeping your nose to the ground to find the most incredible critters. These dive sites are available year-round, and a night dive here is also fantastic.
Diving in Chole Bay
Located in the heart of the protected Mafia Island Marine Park, Chole Bay is one of the island’s most biodiverse areas. You will find vast, healthy coral reefs with a remarkably wide variety of hard corals – unique to this region. The bay is full of life: from schools of colorful reef fish to turtles, stingrays and barracudas. Each reef has its own character and attracts different species. Because Chole Bay is well sheltered, you can dive here safely and comfortably all year round – ideal for beginners and experienced divers alike.
Diving outside Chole Bay
Diving outside Chole Bay is challenging: the dives are deep and there can be strong currents. There are beautiful walls, reefs and a number of channels you can drift through. You can see the bigger stuff here: green turtles, groupers, reef rays and you can spot pelagic species. These dive sites are only available during the Kaskazi wind season – usually from October to March.
Marine life on Mafia: what to expect during your dive?
The underwater world around Mafia Island is among the most biodiverse in the western Indian Ocean. Thanks to its location within the protected Mafia Island Marine Park, the reefs here are exceptionally healthy and rich in life. You’ll find both small macro life and large pelagic species here, with current-rich dive sites ideal for drift diving.
Mafia is best known for its predictable whale shark season (from October to February), but even those who prefer to scavenge on the reef for peculiar little creatures come here in full force. It is a paradise for underwater photographers as well as adventurous divers.
Sharks & rays
- Whale shark (high season: Oct-Feb, often snorkeling!)
- Blacktip Reef Shark
- White tip reef shark
- Nurse Shark
- Gray reef shark (sometimes in deeper water)
- Eagle ray (eagleray)
- Stingray (stingray).
Reef fish & schools
- Barracudas (large schools)
- Snappers
- Horse-eye jacks & bigeye trevallies
- Parrotfish
- Trumpfish
- Lionfish.
- Butterflyfish and angelfish
Other marine life
- Moray eels (spotted and giant moray)
- Cuttlefish & cuttlefish
- Anemones and sponges
- Large groupers
- Tuna
- Octopuses (especially on night dives)
Macro & soil
- Seahorses (especially in seagrass beds at Chole Bay)
- Slugs (many species in the Marine Park)
- Shrimp and small crabs
- Lobster
- Sea cucumbers
- Starfish
Sea Turtles
- Green sea turtle
- Common hawksbill turtle
You can even see baby sea turtles on Juani beach! Between June and September, hundreds of young turtles find their way to the sea on this beach.
Rare or special
- Humpback whales (August and September).
- Hammerhead shark (possibly in deeper water, rare)
- Dolphins (sometimes at the outer reefs or during the boat ride)
- Marlin/sailfish (very rare, opportunity in open water)
Turtle hatching
It does not take place underwater, but it is without a doubt one of the most extraordinary nature experiences on Mafia Island: the hatching of sea turtles. Between June and September, hundreds of young turtles emerge from their nests on remote Juani Island. As soon as they break through the sand, they instinctively rush toward the ocean – a fragile and fascinating race for survival.
To experience this spectacle, take a trip by traditional dhow boat, followed by a short walk through pristine nature to the beach. There you can – with any luck – witness live how the newborn turtles take their first steps toward the sea. A magical, intimate moment that will stay with you for a long time.
Whale Sharks at Mafia
Mafia Island is one of the best places in the world to spot whale sharks. These gentle giants come to the waters west of the island every year between October and February, where they feed on plankton. The unique thing about Mafia is that the whale sharks here swim right under the shore, just 5 to 10 minutes by boat from Kilindoni.
You don’t even have to dive to see them; a snorkeling trip is often enough to come face to face with these impressive animals, which can grow up to 12 meters long. What makes it extra special: visibility is often good, the water is warm, and you’re usually on the water with only a few other snorkelers. The chances of meeting them are high, especially in November and December.
Humpback whale spotting
Less well known, but just as spectacular: from July through September, humpback whales migrate along the coast of Mafia Island. These migrating whales come from Antarctica to mate and have young in the warm waters of the Indian Ocean.
During boat trips for diving or snorkeling, you can often see them jumping on the surface or showing their tails. Sometimes you can even hear their singing underwater while diving. The greatest chance of an encounter is in August and September, when mothers with calves stay relatively close to shore. Although you won’t swim with them, they are unforgettable encounters that give your diving vacation a magical edge.
What diving equipment do you need on Mafia?
Diving on Mafia does not require extremely specialized equipment, but it is important that you know what you need. Here is a list of the most common equipment for diving in Mafia.
Basic equipment
- Wetsuit: In the warm waters of Zanzibar, a 3 mm shorty or full wetsuit is usually sufficient. During the dry season (March to June) and night dives, a full 3 mm wetsuit can provide some extra comfort. For most dives, a thicker suit is not necessary.
- Mask & snorkel: A well-fitting personal mask is recommended for optimal visibility and comfort. The snorkel is especially useful when waiting for the boat or during snorkeling time.
- Fins: side dives can be made actually, so probably open fins with shoes are the best choice. As a result, you never have to walk barefoot.
- Dive computer: Highly recommended for safe diving and to keep a good record of your dive profile, especially if you are going to make several dives a day and during the week.
- BCD & regulator: You can often rent fine at local dive centers, but own equipment always gives comfort.
Additional accessories
- Underwater camera: Mafia has beautiful marine life, coral reefs and lots of muck and macro, so a camera or actioncam is great for capturing your memories.
- Weights: You don’t need to bring this, of course, but it’s good to know. Because of the warm water, you often need less lead than in colder waters.
- Diving gloves and boots: Not necessary due to the soft coral and warm water, but boots can be nice for comfort.
- Dry bag: Since these are mainly boat dives, it is convenient to bring a dry bag for valuables. A dry bag is specially designed to keep belongings dry during boat trips. They are often made of sturdy, waterproof material with a roll-up closure at the top to keep water out.
Diving on Mafia with EWDR
Want to experience Mafia for yourself? We have a wonderful trip where you spend 5 days diving on Mafia and then continue to mainland Tanzania for several days of safari. This is how you truly discover the best that Tanzania has to offer. Check out the trip below or request a no-obligation trip proposal.
Check out our trip to Mafia Island here