Conserving Mangrove Ecosystems in the Philippines Transcending Disciplinary and Institutional Borders
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J. Farley, D. Batker, I. de la Torre and T. Hudspeth


Humans are rapidly depleting critical ecosystems and the life support functions they provide, increasing the urgency of developing effective conservation tools. Using a case study of the conversion of mangrove ecosystems to shrimp aquaculture, this article describes an effort to develop a transdisciplinary, transinstitutional approach to conservation that simultaneously trains future generations of environmental problem solvers. We worked in close collaboration with academics, non-government organizations, local government and local communities to organize a workshop in Puerto Princesa, Palawan, Philippines. The primary objectives of the workshop were to: (1) train participants in the basic principles of ecological economics and its goals of sustainable scale, just distribution and efficient allocation; (2) learn from local community stakeholders and participating scientists about the problems surrounding conversion of mangrove ecosystems to shrimp aquaculture; (3) draw on the skills and knowledge of all participants to develop potential solutions to the problem; and (4) communicate results to those with the power and authority to act on them. We found that the economic and ecological benefits of intact mangroves outweigh the returns to aquaculture. Perversely, however, private property rights to mangrove ecosystems favor inefficient, unjust and unsustainable allocation of the resource—a tragedy of the non-commons. We presented the workshop results to the press and local government, which shut down the aquaculture ponds to conserve the threatened ecosystem. Effective communication to appropriate audiences was essential for transforming research into action. Our approach is promising and can be readily applied to conservation research and advocacy projects worldwide, but should be improved through adaptive management—practitioners must continually build on those elements that work and discard or improve those that fail.

Main Results and Conclusions:
  • There are many problems associated with the conversion of mangrove habitat to aquaculture operations: “Aquaculture pollutes local waters with effluents, spreads disease, and by pumping vast amounts of fresh groundwater, often draws saltwater into coastal aquifers, damaging the water supply of local communities” (41).
  • Ecosystem goods and services provided by mangroves: gas regulation, climate regulation, disturbance regulation, supply of raw materials, water supply, water absorption capacity, erosion control & sediment retention, nutrient cycling, pollination, biological control, Refugia or habitat, genetic resources, recreation and culture (42)
  • Out of all mangroves in the Philippines, 15% reside in Ulugan Bay. Within Ulugan Bay’s proximity, the current study was conducted with a low-income fishing and farming community known as Barangay Tagabinet (41).
  • Lasting problems associated with mangrove habitat destruction were observed: “While intensive aquaculture is often short lived, mangrove destruction endures. We saw a cleared mangrove forest that had failed to recover even after six decades of abandonment, probably due to changed hydrodynamics, salinity, and acidity, as well as low nutrient levels and loss of essential substrates”(46).
  • To combat these problems and protect the mangroves of Ulugan Bay, a transdisciplinary method, known as post-normal science (PNS), was adopted. The techniques involved in PNS are as follows: “First, given pervasive uncertainty and conflicting values, it extends the notion of expertise to include the knowledge and values of stakeholders intimately familiar with the system and not limited by disciplinary blinders. Second, it recognizes the value of folk wisdom, local knowledge, anecdotal evidence, investigative journalism and small-scale surveys in decision-making as well as expert opinion and conventional scientific evidence. Third, it accepts that urgent decisions with high stakes must be made with limited information, and recognizes a cost of acquiring more information is the possibility of irreversible and catastrophic outcomes. Finally, PNS reassesses how to evaluate the quality of a decision” (43-44).
  • Communication among all parties was very important in this study: “One of the most important tasks of conservation science is to communicate results to those with power and authority in a way that stimulates them to act. In the case of the Tagabinet study, that meant government officials. Here again the NGO partners proved particularly valuable owing to their experience in communicating with governments and media. Once we had satisfactorily synthesized the results of our analyses, our NGO partners arranged for a press conference”(47).
  • The mangrove conservation project proved to be a success. In conclusion: “Following the final press conference, the community demolished the newest aquaculture ponds. Functioning ponds were left intact to allow harvest, but those too were drained within a few days. In addition to the dike destruction, Mayor Hagedorn implemented a mangrove restoration and monitoring plan for the City of Puerto Princesa. Five months after the workshop, school children planted 10,000 mangroves in former mangrove habitat, and annual reforestation projects continue”(48).


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