Forty years ago, I predicted that fully protecting coral reefs from fishing would build up fish abundance and biomass in such reefs.
These protected reefs, which my Australian colleague, Prof. Garry R. Russ of James Cook University, and I refer to as no-take marine reserves, are expected to cause a net export (spillover) of adult fish from the reserve to the fishing area immediately outside the reserve.
This spillover would initially increase fish catch of fishers and maintain over a long period of time a high level of fish catch as long as the no-take reserve is fully protected. And this protection in our model is the responsibility of local fishing communities and LGUs.
I also predicted that protection would improve the marine biodiversity of coral reefs and would make marine reserves a tourist destination.
Under proper management, marine reserves would bring incomes to coastal communities. Apo Island, Dauin as well as Zamboanguita and Amlan towns, are now earning substantial incomes from user fees.
In the 1980s and 1990s, Professor Russ, Dr. Rene Abesamis of our Center, and I confirmed the first prediction by publishing the results of our natural experiments from our study islands of Sumilon and Apo in the Central Visayas.
At this time, another important role of no-take marine reserves, that of producing fish larvae to replace the adult fish individuals caught by fishers, is being demonstrated by our research program.
Spillover of adults from marine reserves that augment fish catch appear to be the primary reason why so many people, including local government units, local people’s organizations, NGOs, and academe, have embraced the concept of marine protected areas and have established more than a thousand small no-take marine reserves in the whole Philippines, no doubt the influence of our two marine reserves in the Central Visayas.
Despite our findings and those of many other scientists all over the world, there are still doubters of the important role of no-take marine reserves (especially the small ones) in bringing back the fishery productivity of many resource-depleted fishery grounds in the world.
Some argue that marine reserves are not sufficient; they must be supplemented by other means of management. Yet, these critics are also aware that practically all fishery management practices in developed countries have been found wanting in stopping the continuing decline of fisheries in the world.
We firmly believe that fully protected no-take marine reserves occupying at least 15 to 20 percent of the total fishing area is the most promising answer to the world’s problem of fishery depletion through increased fish biomass and larval connectivity.
The recent findings of the SUAKCREM and the James Cook University research team headed by Dr. Abesamis show the benefits of marine reserves to fisheries (larval connectivity), thus far, hidden from most people.
Through simulation, Dr. Abesamis and his team showed that the 39 small community-based marine reserves, occupying only 6% of the coral reef area in the Bohol Sea, are expected to produce a 2.0, 3.4, 4.0-fold increase in larval settlement, if these reserves had been protected five, 10, 20 years, respectively. If the area of the reserves is increased to 15 percent, there would be an eight-fold increase. These findings show the necessity of full protection of no-take marine reserves to ensure long-term, sustained fisheries.
Our research program on no-take marine reserves has entered a new phase in this century in that the mechanisms whereby no-take marine reserves ensure sustainable fisheries are being elucidated and explained in simple terms to the Filipino people.