Following the return of Frontier within the Marine Park boundaries, near the village of Utende, monitoring efforts are now concentrating on investigating the impact of the Marine Protected Area (MPA) since its establishment in 1995.
Preliminary studies of fish abundance already showed some very encouraging results. Diversity of target species is twice as high within the MPA compared with areas outside the park, and the abundance is double that of the heavily fished areas outside the Marine Park. Specifically, trigger fish were found to be 6 times more abundant within the MPA. The increase of trigger fish is particularly beneficial to the coral reefs because these species prey on the coral nemesis, the Diadema urchin. The most recent surveys of invertebrate abundance indeed indicate a 60 fold decrease of the predatory Diadema urchins, hopefully giving some relief to the coral reefs of Mafia Island Marine Park.
Data collected this year also suggests that the benefits of the Marine Park may extend beyond its borders. Although there are fishing restrictions imposed within the MPA, it is hoped that long-term benefits will be enjoyed by local fishermen fishing in nearby waters due to the over-spill of fish from inside the Marine Park. Indeed, initial studies show an increase in both fish abundance and biodiversity in bordering waters outside the MPA despite the fact that these areas experience high fishing pressures.
Future studies by Frontier in Mafia Island intend to further explore the potential benefits of over-spill. These initial encouraging results suggest that protecting the marine environment not only benefits the animals living within it but may also yield important commercial benefits to the local communities.
Rosanna von Zweibergk
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