MAFIA ISLAND MARINE PARK
 
The proposal to establish marine parks in Tanzania was first made in the late 1960s after Tanzania's independence from Britain. Protection of coastal areas and marine reserves was recommended along the 800km Tanzanian coastline through the creation of marine parks, reserves and sanctuaries.

This led to the creation of eight small reserves under the Fisheries (Marine Reserves) Regulations of 1975. Two of these reserves (Chole Bay and Kitutia Reef) have been incorporated into the Mafia Island Marine Park.

The small size of the original eight reserves, coupled with their limited financial and human resources, meant that they were essentially "Paper parks". Dynamite and unsustainable resource exploitation continued.

This in turn led to the recognition that there is a high level of economic dependence on marine resources in Tanzania and that the traditional approach ( in terrestrial areas) to conservation of establishing exclusion zones is unlikely to be effective in the marine context.

An alternative approach is to establish larger marine areas where protection of fisheries, reefs and marine resources can be conducted in conjunction with sustainable resource-management, and through zoning and participatory management attempt to minimize conflicts between livelihoods and conservation goals.

In 1991, a committee was appointed to oversee the development of Mafia Island Marine Park. This committee comprised the Fisheries Department, Institute of Marine Sciences, the Mafia Member of Parliament, the World Wildwide Fund for Nature, Regional Natural Resources office and the Wildlife Conservation Society of Tanzania.

Late that year, the Rome based Food and Agricultural Organisation and the Tanzania Attorney-General's office began drawing up the enabling legislation. In 1992 the Worldwide Fund for Nature (WWF) instituted a programme of support for the development of marine park.

In October 1991, a public workshop drew over 70 participants to consult the communities involved and initiate the planning process. The proceedings of this workshop were published.

This long and typically bureaucratic but very democratic, process was finally concluded on November 1994 when the Tanzanian parliament passed the Marine Parks and Reserves Act No 29.

Approximately 18,000 people live within the 14 villages that lie wholly or partially within the boundary . Four of these on Chole, Jibondo, Juani islands and Kungwi near Mlola forest are entirely within the park. Another uninhabited island, Bwejuu, is wholly within the park boundary and is a sub-village of Killindoni.

FLORA AND FAUNA:

The sea around Mafia Island hosts an outstanding mosaic of tropical marine habitat including coral reefs, sea grass beds, mangroves and inter-tidal flats. In addition, a remnant block of threatened lowland coastal forest on the eastern side of the island is incorporated into the park.

Most of the marine area of the park is less than 20 metres below mean tide levels. This area includes much of Chole Bay, the extensive area south of the bay enclosed by Mafia Island, Jibondo and Juani islands and several reef areas south of Bwejuu.

Extensive inter-tidal flats stretch along the southern part of Mafia Island, around Chole and Juani islands and between Jibondo Island and Kitutia Reef.

A channel of 20 to 30 metres in depth carries tidal water through Kinasi Pass and Chole Bay as far as the Chole channel. The waters on the southwester side of the marine park, especially those west of Kitutia reach a depth of 40 metres.

The main ocean current affecting Mafia Island is the permanent north-flowing East African Coastal Current. This reaches a maximum speed of 4,5 knots during the peak of the southeast monsoon (kusi) in June- July. This is somewhat countered by the northeast monsoon (kaskazi) during December- January.

The flow of the main current into and through the marine park area is interrupted by the islets and reefs, and is also strongly influenced by diurnal tidal currents generated by a tidal range of up to 4 metres. This results in a complex and multi-directional current system.

The tidal range in the marine park is consistently large during the year. The mean spring-tide range is 3.3 metres with a maximum of 4 metres. This neap-tide range is approximately 1.5 metres.

The sheltered western side of Mafia Island is heavily influenced by sedimentary material discharged from the mainland.

What direct influence the Rufiji Delta, facing Mafia, has on this is unclear. The visible sediment plume emanating from the delta appears mostly to be carried northwards by the prevailing East African current before it reaches Mafia's west coast even after heavy rains.

Sub-tidal habitats are largely sandy or soft-bottom, including extensive sea grass beds. There are a number of hard reefs to the southwest of Mafia, further from the reach of the delta that are sheltered by Bwejuu Island.

The eastern side of Mafia is exposed to the full force of the Indian Ocean and a 33 km outer fringing reef stretches along of the full length of the eastern seaboard and encompasses Mafia, Jibondo and Juani Islands with Kitutia Reef lying at the southernmost point.

The main fringing reef is gently sloping and dominated by hard corals though in some sections these coral suffered high mortality as a result of abnormally high sea temperatures following the 1997 El Nino. 

The outer part of Kinasi Pass is characterised by shallow platforms dominated by soft coral and algae giving way to dramatic vertical reef wall which bottom out into sandy platforms between 20 and 50 metres in depth. Mafia Island lines the edge of the continental shelf and the underwater area shelves steeply into the open ocean.

Chole Bay, a large enclosed body of water, floods and drains twice every day through Kinasi Pass. The main inner section of Kinasi Pass, together with the sheltered area south of the pass, has a highly diverse topographic structure and hydrology, and the highest diversity of hard coral and other reef species is found in this area.

Other sheltered sub-tidal areas going west from Chole and Juani Islands across to Mange Reef and Bwejuu Island, are less species rich ,characterised by shallow algae and coralline reef platforms and sandy areas studded with coral bommies. There are also significant patches of sea grass in these areas especially to the western side.

The predominantly north flowing current may place particular emphasis on the importance of reefs at the southern end of the marine park, especially Kitutia Reef, in terms of the dispersal of seed and larvae of corals, fish and other marine organisms.

Habitat distribution, level of disturbance and species diversity vary greatly between the eastern and western sectors. Habitats in the western sector towards the Rufiji delta show greater levels of disturbance, are in comparatively poorer condition and contain less species diversity.

In contrast, Chole Bay and outer parts of Kinasi Pass have greater habitat diversity, greater species diversity within these habitats and are less disturbed. The deeper reef walls in Chole Bay and on the outer reef are still relatively pristine.

The presence of mangroves, sea grass beds, algae, sponge and soft coral beds, the fringing coral reef and adjacent algae-dominated reef outside Kinasi Pass, means that Chole Bay possesses representative examples of the majority of tropical marine ecosystems.

Mangrove are known to play an important role in the life cycle of some fish and shellfish, as well as protecting coastlines from wave action and storms. Most of the mangroves in Mafia are relatively narrow stands fringing the shores and creeks.

Within the marine park mangroves are concentrated along sections of the northern shore of Chole Bay at Mchangani, Kapingwi, Kipandeni and Marimbani around Juani Island except where it faces the ocean and at Mto wa Arusha to the north of Ras Kisimani.

Outside the marine park there are relatively large mangrove stands at sites up the west coast, especially at Chunguruma and around Jojo and Banja villages. There are none along the eastern coast because of the exposure to the ocean.

The extensive inter-tidal flats dominating the south of the park were formerly abundant in mollusk and other invertebrate fauna that have been heavily exploited. Today they are an important and productive habitat for octopus.

MAFIA DIVERS PARADISE:

For the expert or novice diver, as well as for the beginner and snorkel, Mafia Island Marine Park offers dramatic underwater viewing with a wide variety of choices- and all this only 30 minutes away from the hotels.

The visibility is roughly 5 to 10 metres from June to September and 20 to 25 metres from October to February. Visibility in Chole Bay can be poor at low tide but you can dive or snorkel in the bay in any weather. Mafia Island justifiably claims to be one of the best diving locations on the African coast.

The favourite dive at Mafia is Kinasi Pass where the ocean comes into the bay. A slope drops into a wall from 16 to 26 metres in height and a massive 'pinnacle' greets divers. There is reasonable coral in shallower water 5 to 15 metres below the surface.

In many Indian Ocean coastal regions, living shallow water corals, terrestrial fossil coral rock and even mollusk shells are used as sources of calcium carbonate and baked in kilns for lime production. Mafia is no exception and the non-branching shallow water genera such as porities are frequently the victims.

FISH:

The coral lumps are taken from the seabed at low tide and heaped on timber (usually mangrove or coconut wood) that are then set on fire converting the calcium carbonate to calcium oxide. The calcium oxide is lime that, mixed with water, produces whitewash or, mixed with sand or earth, produces a simple mortar. Sometimes coral lumps are used as building blocks.

The removal of the coral affects inshore current patterns and wave action exacerbating coastal erosion. This all has a detrimental impact on the productivity of shallow lagoons and bays and this is part of the reason why Mafia Island marine Park has been established.

Nevertheless, fire, starghorn and foliose (48 genera of hard corals) are plentiful and there is a good range of coral throughout the main reefs in the bay while branching corals are also common.

This existing coral cover provides the perfect ecosystem for small reef fish like angel with their pouted lips, distinctive black-and -white striped Moorish idols, damsel fish, parrot fish with beak-like mouths, fusiliers and the colourful wrasse family that is both large in numbers and variable colour

There are nine species of fusiliers in the region and they are colourful, fast swimmers that are seen in shoals. They feed on plankton and are distinguished by their small mouths with protruding jaws and forked tail fins.

One of the most common is the goldstriped fusilier that is known in Kiswahili as mbono or kiunda and scientifically as Caesio caerulaureus. This 24 cm fish has a blue-edged stripe running along the centre of its body separating a darker blue on its back and upper side from a lighter blue on the belly. It is to be found around coral reefs and deep lagoons and it shelters in cervices at night.

The wrasse is usually an elongated fish with continuous dorsal fin. They have well-developed lips, protruding canine teeth and most species are brightly coloured. Like land animals and birds their colouring can vary greatly between juveniles /adults and ,male / females.

The cigar wrass3, known in Kiswahili as mboo ya mvua or mgeema is scientifically,
called Chelio inermis. It is shaped like a long cigar and is about 50 cm in length with variable colours ranging from yellowish to greenish or brown. This fish may have a mid-lateral dark stripe and the males may have a dark spot near the pectoral fin. They feed on sea grasses or dense algae beds.

The somewhat longer queen coris (scientifically known as Coris formosa) and the Goldbar wrasse(Thalassoma hebraicum) are the most colourful members of the whole family.

The juvenile queen coris is bright reddish-orange with three balck-edged white patches on the back and flanks and two smaller white patches on the head. Adults have elongated front rays on the first dorsal fin and a blue stripe from the front of the dorsal fin to the mouth.

The females are brown with large dark spots and red bands across white-edged tail fin while the males are lavender- blue with light orange bars on their flanks. They are to be found among coral and sea grass beds.

Juveniles of the goldbar wrasse have black longitudinal rows of yellow spots and yellow bar from the front of the dorsal fin to the belly. Adult males have yellow heads with diagonal stripes, a greenish-blue body with thin yellow stripes.

Groupers, known in Kiswahili as chewa, are robust-looking fish. Off Mafia they can be two metres in length. They have large mouths and are generally inquisitive. But in areas of intense fishing, particularly where spear fishing is practiced, they are wary. They are much sought after as food for humans and reef stock are easily over-fished.

Small scholars of barracuda are often sighted, especially in Kinasi Pass. They are distinguished by their elongated bodies and pointed heads, large jaws and big teeth and two widely separated dorsal fins. Seven species of barracuda exist in the Indian Ocean.

In Kiswahili different species of barracuda are variously known as tengezi and mzira. The pickhandle barracuda is about 125 cm in length, silvery in colour with 20 darker vertical bars running halfway down its body. It has large eyes, a lower jaw projecting beyond the upper and it feeds off medium-sized fish and squid.

Rainbow runners, black jack and lockdown jack compete for the best positions and black-spotted ribbon-tail stingray surround the divers in circular dance. Spotted eagle rays often add their spectacular acrobatic show.

Black-spotted ribbon-tail stingrays grow to 250 cm in length, including their tails, and 100 cm in width. They are called nyenga in Kiswahili and are large, heavy-set rays with a rounded body and short tail that is mottled blue and grey above and white below. They are often found in caves and their preferred habitat is close to reefs, down to deepwater.

The blue-spotted ribbon-tail stingray that also exists in the western Indian Ocean, is slightly smaller and is found in shallow, sheltered waters around reefs and under coral patches. It has a broad oval body, is olive-brown in colour with many bright blue spots and its blue-striped tail has a single sting.

There are at least two species of eagle rays in the Indian Ocean and they are known in Kiswahili as pungu pua or pungu piji. They are 350 cm wide, have numerous white spots and long tails with one or more serrated barbs at the base. They feed on mollusks and crustaceans and are found inshore near coral reefs.

Powerful manta rays known in Kiswahili as taa chui also can be seen near the surface, occasionally jumping clear of the water. They are 670 cm wide and weigh up to two tonnes, have broad heads with paddle-like head flaps, five pairs of gill openings for filtering plankton and thin whip-like-tails.

Inside the bay as a result of conservation, most of the corals are increasing in number and size and the fish inside the bay are greater in numbers but smaller in size than those found in deeper water.

Dindini Wall (also known as Mchangani Wall), together with Jina Wall, is one of the best dive site outside the bay. Long vertical walls start at 5 metres and drop to 25 metres. While coral variety is not as good as in the bay, the vista is nevertheless dramatic with a few caverns and a good range of big fish. 

The outer reef on the ocean side of Juani Island (to the left/ south of Kinasi Pass) is also a beautiful reef rich in soft corals in myriad shades of mauve, indigo and purple. There is also a high chance of sighting green turtles on this reef.

Torpedo-shaped and robust yellow-fin tuna known in Kiswahili as jodari swim swiftly in shoals while kingfish or narrow-barred Spanish mackerel (nguru in Kiswahili). Indian mackerel or bigmouth (kibua), queen or spotted mackerel (kanadi), stroped bonito (salehe), skipjack or oceanic bonito(zanuba), kawa kawa (sehewa) and wahoo (nguru ngazija) may also be seen.

Cobia (songoro) with its elongated body, flattened head and large mouth, is often found in open coastal water, often in association with other larger fish and sharks. Often there are reef sharks that have narrow and slender bodies and are known i Kiswahili as papa. These sharks have been known to attack people although of the more than 50 species of shark that exist in the Indian Ocean the majority are completely harmless.

Sharks, barracuda, groupers, needlefish, moray eels and triggerfish are capable of inflicting bites on the overly intrusive diver. Shark attacks are the most feared but are very rare. Sensible behaviour around sharks and other large fish and consultation with local people will minimise the danger of them attacking you.

There are over 2,000 different fish from more than 150 families in the western Indian Ocean that encompasses the African coastline and new species are being added.

TURTLES:

Mafia and the surrounding islands, are important nesting sites for Green and Hawksbill turtles while Leatherback, Olive Ridlely and Loggerhead also occur in Mafia, although they do not nest.

The green turtle is the biggest of the species weighing from 120 to 208 kg and being up to 140 cm in length. In colour they vary from dark brown or black to greenish-brown. Adults are mainly herbivorous feeding on sea grasses and occur in relatively shallow water.
In contrast, juvenile Hawksbill feed on floating vegetation while the adults mainly feed on bottom-dwelling invertebrates such as corals, sea urchins and sponges.

The Hawksbill is identifiable by its thick overlapping plates, its narrow, pointed head and long, almost bird-like beak.

An ongoing protection programme has recorded over 150 nests in 2002 and this is certainly an under-estimate. Each female nests 2-3 times in one year and then not for 3-4 year which confuses the picture on how many turtles there actually are.

It is estimated 70-100 female green turtles visit per year (so maybe 3-400 in total over a 4 year cycle). Hawksbill are much fewer, perhaps 10-20 females per year.

A major protection initiative over the past 2 years has drastically reduced the number of nests that were being poached( for eggs) and females slaughtered by fishermen. The rate of poaching was at least 50 % before and has gone down to 5%.

Through snorkeling or diving, these fish can be observed in their natural environment. Their colours, behaviour and relationships with other marine organisms are an endless source of fascination. That is rather like viewing land mammals ( that arrived on this planet later than fish).

There is a word of warning for divers and snorkels, particularly the first timers. The western Indian Ocean, in common with other oceans, contains marine animals that can inflict harm on the unwary. Furthermore, the tropical coastal environment carries its own dangers. Most coastal people are fully aware of these dangers and although very few visitors are infected but it is as well to be aware of them and to treat them accordingly.

Sunburn is one of the most common infections, particularly as the hottest season in Tanzania coincides with the best diving season. Sensible covering such as a T-shirt, even when swimming, a hat when onshore and sun creams will minimise this threat.

Small wounds in the high humidity and temperatures can swiftly become septic unless treated early. Beyond that, care and sensible foot protection when walking on the beach or in the sea, is advised.

Malaria is a common tropical disease. Mosquitoes are active from sunset to sunrise so sleeping under mosquito net, repellants, long trousers and socks at night are vital. Before leaving home consult your local doctor about the prophylaxis you should take.

A simple rule for all divers and snorkels is do not handle anything at with your hands and not stand up- stay horizontal/ floating. Beyond that you should always wear shoes if you are wading through intertidal or shallow waters. 

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