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The coral mining industry was studied in Mafia by Dulvy and Darwall 1995 and Dulvy et al. 1996; in Mikindani Bay, Mtwara region, by Solandt and Ball 1999; and in Kigamboni near Dar es Salaam by Jambiya et
al .1996.
The potential for ecotourism in relation to coral reefs as well as other attractions was reported by Andersson 1998 for Zanzibar and by Hansen 1999, Wagner et al. 2000a, and Wagner et al.2000b for Kunduchi and
Mbweni, north of Dar es Salaam.
4.2.3 Experimental Studies
Most of the experimental studies have been related to the recruitment of corals, coral larval settlement and transplantation of corals.
Nzali et al. 1998 and Nzali 1999 studied various factors coral coverlevel of reef degradation, season, water temperature, rainfall, sedimentation, and orientation of surfaces, i.e., upward facing or downward facing affecting
hard coral recruitment on Taa Reef, a nearshore reef near the northern border of Tanzania. Clay tiles were placed on racks 20 cm above the seabed. After retrieving the tiles, they were examined for coral recruits and data were
recorded on the location of recruits on the upper or lower surfaces, their identification, diameter, and their number.
Ohman et al. 1999 determined the effect of coral bleaching on fish populations. This study was partly experimental, in that it began with the transplantation of corals, and partly observational, in that the 1998 coral bleaching event
occurred in the middle of the experiment. Before and after the bleaching event, they recorded data on live coral cover in the transplanted plots, reef structural complexity, fish abundance, and fish species composition.
Experimental studies that are still underway include a study by Muhando Ph.D. thesis, in preparation on techniques to enhance coral larval settlement and to transplant corals as means of promoting coral reef
rehabilitation or restoration in Tanzania. Franklin et al. 1998 experimented on the effect of coral fragment size on the success of culturing such fragments for potential subsequent use in aquaria or for reef rehabilitation.
Kuguru M.Sc., in preparation examines the competitive effect of Rhodactis spp. Cnidaria: Corallimorpharia on hard corals on selected reefs of Zanzibar.
4.2.4 Applied Studies
Applied studies have mostly dealt with coral transplantation. A study by Lindahl 1998 was both experimental and applied. He attempted rehabilitating coral reefs by transplanting coral fragments using different methods of
attachment, at different densities and different sites.
Wagner et al. 1999 conducted a trial on participatory restoration of the fringing coral reef at Mbudya Island. Fishermen were involved in transplanting corals in dynamite blasted sites. Fragments of Galaxea sp., Acropora
sp., Porites sp., and Montipora sp. from nearby healthy colonies were inserted into cement-filled, disposable plastic plates placed in the damaged areas. Baseline measurements of these transplants were recorded after three
months by Allen 1999 and their growth after 14-16 months was measured by Wagner et al. 2000b. Hansen 1999 transplanted corals in additional sites at Mbudya Island, recording baseline measurements of the
transplants.
4.2.5 Review Studies
Many papers have reviewed the importance and utilisation of coral reefs, particularly in fisheries Ali, 1998; Bwathondi et al., 1988; Jiddawi, 1998. Many others have discussed management issues Horrill et al., 1994;
Makoloweka et al., 1996; Horrill, 1997; Horrill and Kalombo, 1997a, b; Shah et al., 1997; Horrill and Makoloweka, 1998; Kalombo and Horrill, 1998; Mambosho, 1998; Msuya, 1998; Semesi et al., 1998.
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Horrill et al. 2000 reviewed the coral reefs of northern Tanzania with respect to distribution, condition, physical and chemical characteristics as well as socio-economic and management issues; while Darwall et al. 2000
reviewed similar aspects for southern Tanzania.
Muhando 1999 reviewed the extent of reef damage and socio-economic impacts caused by the 1998 coral bleaching event and discussed the subsequent recovery of reefs.
Guard and Masaiganah 1997 reviewed the findings of the marine biological and resource use surveys which were conducted by Frontier-Tanzania in southern Tanzania, discussing the extent of damage by dynamite fishing,
the intensity of its use, geographical variations Kilwa, Lindi and Mtwara and recommended possible solutions.
Wagner 1997, 1998a reviewed impact of various types of fishing on coral reefs, while Wagner 1998b, 1999 reviewed the importance, threats, conservation and restoration of coral reefs.
4.3 Research methodology
