The Dive Sites at Mafia Island
THE DIVE SITES
We are indebted to FRONTIER Tanzania for some of the information in the text which follows. Their report on the diving in Mafia – The Guide to the Diving of Mafia Island: an Unexplored Paradise – is in the Kinasi library.
Chole Bay is blessed with a number of excellent dives within the Bay, ensuring diving in almost any weather, as well as easy access. Visibility varies with the wind and tides, and is generally poor on outgoing tides as there is the normal accumulation of organic and granular matter in the water. The diving is tide-dependent for this reason and also to avoid strong currents at the dive sites which are close to the mouth of the Bay (Kinasi Pass). We usually dive on the full low, full high or on the incoming tide for the Kinasi Pass drift dive and the Chole and Kinsai walls. Diving outside the Bay is subject to weather conditions and tides, as it can be dangerous to negotiate Kinasi Pass on an outgoing tide; however, once outside the Bay the dives are not tide dependent.
Almost all Mafia’s best diving is at depths of less than 30m so it is a sport diver’s paradise. The reefs of the archipelago offer a staggeringly beautiful and varied display of marine life. The excellent condition and high diversity of the reefs stimulated the creation of Mafia Island Marine Park, Tanzania’s first marine park. Examples of most kinds of tropical marine habitat occur here, including exposed fringing reefs, rock walls, soft coral and algae-dominated reefs. The diversity of animal and plant life is hard to match, with over 50 genera of corals and 400 species of fish so far identified; many more still await determination. There are excellent examples of giant table corals, delicate seafans, whip corals, and huge stands of blue-tipped staghorn corals. Large predatory fish and turtles are common and surprisingly unaffected by approaching divers.
DIVING INSIDE THE BAY
This is a sheltered bank reef, moderately deep and steeply sloping from 8 to 21 metres. It runs south-east:north-west for approximately 800 m and is an excellent dive on a slack tide or with a slight incoming current. It is in superb condition and composed of many species of hard and soft corals and supports a great variety of shoaling and solitary fish and giant clams, seafans, large groupers, and Napolean wrasse; there are abundant reef and pelagic fish, and turtles (especially the hawksbill) are often seen. One of our most popular dive sites.
Another bank reef that joins the Kinasi Wall but lying north-east:south-west, also about 800m long. A steep bank of coral descending to 15 m, usually with excellent visibility, and ending in coral rubble and sand. A panorama for the diver as there is a startlingly rich tapestry of corals enveloped in clouds of tiny fish, dominated by colourful damselfish and fusiliers; numerous butterflyfish and angelfish. Especially interesting for the many species of colourful nudibranchs and flatworms. This is an excellent night or introductory dive. A great dive full of interest.
A very large area of beautiful coral outcrops or “bommies”, lying in a wedge behind the Kinasi and Chole walls. The coral is very densely packed and continuous behind Kinasi wall; elsewhere the coral is separated by seagrass and sand patches. This is an excellent site for photography with a very high diversity of fish, colourful corals and anemones and the shallow water makes visibility excellent. This is a shallow water dive, often undertaken as the last phase of one of the wall dives. Excellent for snorkellers behind Kinasi Wall at low tide.
THE CORAL PATCHES
This site comprises three extensive and spectacular coral patches at 9 to 17 m that are separated by sand channels. The many species of coral are packed around the ancient Porites formations. There are a large number of dense shoals of fish, equalled only by Kinasi Pass. A peculiarity is the occurrence of large numbers of spotted garden eels, so named for their habit of living together in “gardens” in the sand around the coral.
The Pinnacle is a 12 m spire of ancient coral rock (7o57’005S/39o47’850E) lying in the inner Kinasi Pass, close to the last rock island. Maximum depth is 24m at the base of the spire. This is a spectacular dive for the unusual structure and the mixture of reef and pelagic fish in the channel. Home to a very large potato cod and a very large resident moray in a hole on the “whale-back” of rock that slopes off the western side of the stack and many giant batfish.
After completing a tour of the Pinnacle the diver heads south-west to the side of the channel, the Kinasi Pass dive, rightfully famous as a stunning drift dive. The Pass has two walls, commencing with a deep 20-26 m shelving reef, then a shallower one at 6-15 m. The diver floats along a wall with small caverns and overhangs, with great shoals of juvenile and adult reef fish, barracuda and carangidae that sometimes block out the light, a vast array of corals, parrotfish, large groupers and pelagics coming and going with the tide. A fantastic dive.
Extremely picturesque with unusual coral formations through which the diver navigates. Spectacular layered coral peaks. This is followed by vast Porites formations that are dome-like, with many lionfish, glass fish and moray eels. From here it slopes away to 21 m with a wide variety of soft and hard corals. This site is good in all conditions as it is only slightly affected by currents; an excellent second dive.
This site consists of a small primary reef with a variety of soft and hard corals on slopes and sheer walls down to 15 m. Away from the central formation are spires of coral that provide archways and overhangs for the diver to explore. Beautiful anemones of fluorescent red colour and rays (especially blue spotted) are common. This site is a good introductory dive but has unpredictable visibility conditions.
DIVES OUTSIDE THE BAY
This is a rock wall from 8 m down to 28 m, with caves, caverns, overhangs and an archway; this is the only true rock wall so far discovered and it makes a spectacular and exciting dive. Large groupers, sharks, guitarfish, turtles and basket sponges are features. We have also seen many large pelagics here, including sailfish, very large tuna and dolphins, as the wall lies close to great dropoffs. There is lush growth of sedentary filter feeders and algae on the upper part of the wall; seafans and whip corals lower down.
DINDINI SOUTH WALL
An extension of the same wall, from 9-22 m, this dive is interesting for the many small walls interspersed with shelving reef, offering a great variety of soft and hard corals and more reef fish. There are very many Napoleon wrasse and potato bass. An excellent dive.
JINA PASS WALL
This site is also an extension of the Dindini Wall lying at the northern tip of Jina Island, ranging in depth from 8 m to 20 m at the base of a small, vertical wall that has shallow caverns and overhangs and bottoms out in a gravel field. The site is one of our favourites for a rough-mannered, persistent, overfriendly and very large potato bass who dominates every dive.
A gently sloping fringing reef down to 26 m with many brightly coloured soft corals. Home to many mid-size groupers (Flowery Cod) and inquisitive blue-spotted trevally, which are common on all Mafia dives. This site is close to and a continuation of the fringing reef complex near Kinasi Pass.
KINASI PASS ENTRANCE
The north and south shoulders of the Pass are fringing reefs with dramatic landscapes; here there are excellent stands of pristine staghorn and large table corals. Shoals of juvenile reef and pelagic fish; the red lunar-tailed groupers are common; many parrotfish. Turtles, rays and small reef sharks are often seen, as well as many of the larger ocean-going fish – kingfish, caranx, barracuda, rainbow runner. Both dive sites – on either side of the Pass – slope to 20 m, where the coral peters out to rubble and sand, about 500 m offshore.