Evaluating a marine protected area in a developing country: Mafia Island Marine Park, Tanzania

The benefits of marine protected areas (MPAs) to fish productivity remain debated, and comprehensive research projects have been suggested to assess MPA function. This study evaluated MPA performance in a developing country in the context of local needs. We compared density and size of the blackspot snapper, Lutjanus fulviflamma (Forsskهl 1775), in Mafia Island Marine Park (MIMP), Tanzania, with adjacent intensively fished areas (IFA) using underwater visual censuses (a total of 105, 50-m transects) as well as investigating the catches in the local fishery. The target species was over four times more numerous, its biomass six to ten times higher and individual sizes on an average 37% larger on reefs in MIMP compared to the IFA. Fish numbers and biomass were negatively correlated with fishing intensity and positively correlated with hard coral cover and structural complexity. This study supports predictions that MPAs can play a key role in the conservation of habitats and management of a fishery. It is suggested that for the purpose of management, it is possible to evaluate MPA performance with limited resources by focusing on key information.