Mafia Island: Whale Sharks, Marine Park and the Complete Guide

By Regan Jacob, Tanzania Team Head Guide at Paramount Gorilla Expeditions · Last updated 31 October 2026

Mafia Island is Tanzania's quiet marine hideaway: a low, palm-fringed island south of Zanzibar, off the Rufiji River delta, with a marine park that protects coral reefs and a seasonal gathering of whale sharks, the ruins of old Swahili towns and a handful of small lodges. It is the place for divers, snorkellers and travellers who want the sea without the crowds. This guide explains what Mafia Island is, how the marine park works, when whale sharks visit, how to get there, where to stay and how to add it to a safari. People also search for the same destination as Mafia Island Tanzania, Mafia Island whale sharks, Mafia Island Marine Park, Mafia Island diving, Chole Island, Kilindoni and swimming with whale sharks in Tanzania.

Quick answer

What is Mafia Island known for? Mafia is known for the Mafia Island Marine Park, which covers about 822 square kilometres of coral reef, seagrass and mangrove, for diving and snorkelling in uncrowded water, for seasonal whale shark encounters, and for small, relaxed lodges. It lies off the east coast of mainland Tanzania, opposite the delta of the Rufiji River, and is part of the Pwani Region, not part of Zanzibar. Most visitors arrive by a short flight from Dar es Salaam, or by boat from Nyamisati to Kilindoni, and stay three to five nights.

Mafia Island at a glance

Chapter 01 — What is Mafia Island?

Mafia is an island of about 400 square kilometres in the Indian Ocean, off the east coast of Tanzania, opposite the delta of the Rufiji River and separated from the mainland by the roughly 20-kilometre Mafia Channel. It belongs to Mafia District in the Pwani, or Coast, Region and is not part of the Zanzibar Archipelago, which sits further north. About 66,000 people lived there at the 2022 census, in villages along the coast and around the main town of Kilindoni on the west side.

The island is flat, with coconut palms, mangroves and fishing villages, and its main draw is the sea. Visitors come mainly to dive and snorkel, to watch birds and to fish, and the pace of life is slow. There is no big resort development, and the lodges are small. Our Tanzania destination page places it among the country's coastal and island options, and our Zanzibar destination page covers the archipelago to the north.

Chapter 02 — Mafia Island Marine Park

Mafia Island Marine Park was established in 1995 and covers about 822 square kilometres, protecting coral reefs, seagrass beds, mangroves and the waters around the south and east of the island. It is an IUCN Category VI protected area, which means it is managed for the sustainable use of natural resources, and it is run by Tanzania's marine parks authority. Local villages live within the park, and the rules are designed to protect the reef while allowing local fishing and tourism to continue.

The park's reefs are known for their fish: studies have found that blackspot snapper numbers inside the park are six to ten times greater than outside it, which shows how effective protection can be. Live coral cover was about 14 per cent in a 2003 survey, which reflects the pressures that reefs face across the Indian Ocean. A park fee is charged for visitors, and your written quote shows the fee in force on your dates.

Chapter 03 — Whale sharks

Mafia is famous for its resident whale shark population, one of the few places in East Africa where you can swim with these animals. The whale shark is the largest fish in the world, and the largest reliably recorded was about 18.8 metres long, though typical animals seen near the surface are smaller. It is a filter feeder, harmless to people, and it gathers in plankton-rich water, and it is listed as Endangered by the IUCN.

Whale sharks visit Mafia seasonally, and sightings depend on plankton, currents and the weather. The season is generally given as running from about October to March, with the peak in the middle of that period, and we confirm the window for your year when we plan your dates. Encounters are managed: groups are small, boats keep their distance, and swimmers follow rules on distance and behaviour so the animals are not disturbed. A sighting is never guaranteed, and a flexible plan with two or three days in the season gives the best chance.

Chapter 04 — Diving and snorkelling

Mafia's reefs have coral gardens, walls, channels and a good variety of fish, and the water is warm and clear for much of the year. Most dive sites are inside the marine park, and the lodges and dive centres run boat dives to them. The sites suit a wide range of divers, from beginners to experienced divers, and snorkellers can use the shallow reef on guided boat trips.

Chole Bay and the area around the south of the island have sheltered sites for training and for easier dives, and the outer reefs have more current. Check your certification, and make sure your insurance includes diving. The dry months, from July to October, are generally the best for sea conditions, and the whale shark season overlaps with the later part of the year. Our guide to diving and snorkelling in Zanzibar and the Seychelles explains how Mafia compares with other places.

Chapter 05 — Chole Island and the Swahili ruins

Chole Island is a small island of about 2.3 square kilometres in Chole Bay, with a fossil coral reef about 12,000 years old and the ruins of a historic Swahili settlement. Chole Mjini, the town on the island, was a Swahili settlement under Omani protection in the early nineteenth century, while Kua, the town on nearby Juani Island, was attacked in the 1820s. More than 36 buildings remain on Chole, including a mosque and a number of stone houses, and the island has a small museum.

By the 1960s only three families lived on Chole. Today the island has about 1,500 people in about 350 dwellings. The ruins at Kua, on Juani Island, were documented in 3D in 2018. Germany claimed the island in 1890, and British troops took it on 12 January 1915. A walk through Chole's ruins with a local guide is a good complement to a day at sea, and a visit supports the community that lives there.

Chapter 06 — Birdlife, fishing and nature

Mafia is a good place for birds, with mangroves, forest patches and shores that attract waders, herons and sea birds. Game fishing is another draw, and the channel between the island and the mainland is a fishing ground. Turtles feed on the seagrass and the reef, and a guide can show you where.

Snorkelling off a sandbank, a walk in the mangroves and a sunset on the dhow are all gentle activities that suit the island's pace. Our birding safari guide covers the wider birding of East Africa. For a deeper look at marine life, ask us to include a naturalist guide.

Chapter 07 — When to go

Mafia has one main rainy season, from March to May, with about 1,705 millimetres of rain over the year, and the dry season runs from July to October. The dry months are the most comfortable, with calm seas and the best visibility for diving, and the whale shark season overlaps with the later part of the year, so October is a good month for both.

The wet months can be rough, and some lodges close for part of the season, so confirm which are open for your dates. January and February are often hot, with the sea warm and calm between the rains. Our best time for Zanzibar and the Seychelles guide explains the seasons on the coast, and the same pattern applies to Mafia.

Chapter 08 — How to get to Mafia

Mafia is reached by a short flight from Dar es Salaam, on scheduled light aircraft that land at the island's airport near Kilindoni, and the flight takes less than an hour. This is the easiest way to get there, and the one we normally use. Seats are limited, so we book early.

A cheaper but slower option is the boat from Nyamisati on the mainland to Kilindoni, which takes about four and a half hours. Schedules and fares change, so we confirm them when we plan your trip. Because of the limited transport, Mafia is best planned as a stay of three to five nights. Our guide to fly-in versus road safaris explains how we think about internal flights.

Chapter 09 — Where to stay

Mafia has a small number of lodges and guesthouses, most on the eastern and southern coasts and around Chole Bay. They are small, personal and relaxed, often with a dive centre on site, and they range from simple bandas to comfortable lodges with sea views. There is no big resort development, and that is the island's character.

We choose by position, comfort and what you plan to do: a lodge near the whale shark launch point, a bay lodge for diving or a quiet place for rest. Rooms are limited, so book early for the whale shark season. Our Tanzania safari lodges guide explains how we choose places to stay across the country.

Chapter 10 — Costs and fees

Mafia's costs fall into four parts: the flight or boat, the lodge, the marine park fee and the activities. The marine park fee is set by the park authority and is charged per person per day, and diving, whale shark trips and boat excursions are priced by the operators. The fees change, and we do not give a single figure here: your written quote itemises each one for your dates, so you can see what is included.

Mafia is generally good value compared with Unguja's leading resorts, but the whale shark season and the flights can add up. For a view of how an island stay fits a wider budget, see our Zanzibar beach tours, and our Tanzania safari cost guide for the safari side.

Chapter 11 — Combining Mafia with a safari

Mafia is a good finish to a southern safari: Nyerere is close to the Rufiji delta, and a flight from Dar es Salaam takes you to the island in under an hour. It also works after Ruaha or the whole southern circuit, and our southern circuit tour shows how we build one.

For a different beach experience, combine Mafia with Unguja or Pemba, or fly from Mafia to Zanzibar. A northern safari can also end here, via Dar es Salaam, for divers who want a quieter coast than Zanzibar. Our guide to adding Zanzibar to your safari explains how we place an island stay after the bush.

Chapter 12 — Mafia compared with Zanzibar and Pemba

Zanzibar's Unguja has history, Stone Town and a wide choice of resorts, and it is the island for variety. Pemba has steep dive walls, forest and cloves and is the one for nature and quiet. Mafia has the marine park and the whale sharks, and it is the one for marine life and for travellers who want the sea and little else.

If you only have time for one island and you want a beach holiday with choice, Unguja is the easiest. If you are a diver or a naturalist, Mafia and Pemba reward the extra effort. Our guide to Zanzibar beyond the beach and our Seychelles guide cover other island options.

Chapter 13 — Practical planning for Mafia

1. Plan three to five nights, so the journey is worth it.
2. Travel from July to October for calm seas, or October to March for whale sharks.
3. Book early for the whale shark season.
4. Allow two or three days for whale shark trips, because sightings are not guaranteed.
5. Dive with a reputable centre, and check your certification and insurance.
6. Follow the rules with whale sharks: keep your distance and do not touch.
7. Dress modestly in villages.
8. Carry cash, because card use is limited.
9. Check your vaccinations. See our malaria and vaccinations guide.
10. Ask us to plan it: we confirm flights, lodge and fees on your written quote.

Chapter 14 — Mafia myths and mistakes

• "Mafia is part of Zanzibar." It is not. It is part of the Pwani Region of the mainland.
• "Whale sharks are dangerous." They are filter feeders and harmless to people.
• "A sighting is guaranteed in season." It is not. Plankton, currents and weather decide.
• "Mafia is just for divers." It is also for snorkellers, birders and history lovers.
• "You can touch the whale sharks." You cannot. Keep your distance, as the rules say.

Chapter 15 — Mafia for kids

Our verdict

Mafia is the island for travellers who want the sea in its natural state: a protected marine park, a seasonal whale shark gathering, quiet reefs and a few small lodges. It asks for a flight, a few nights and a flexible plan, and it gives back a coast that feels unhurried and uncrowded. Travel between July and October for calm seas, or in the later months of the year for whale sharks, and consider pairing it with a southern safari or with Zanzibar. Tell us your dates and we will build the route and confirm the lodge, flights and fees on your written quote.