Illuminating the need for ecological knowledge in economic valuation of mangroves under different management regimes -: a critique

This is a commentary on a paper by Gilbert and Janssen (Gilbert, A.J., Janssen, R., 1998. Ecol. Econ. 25, 323-346) that deals with valuation of management alternatives for the Pagbilao mangroves, Philippines. Our main critique focuses on the undervaluation of fisheries as well as the inability to quantify the value of ecological services and internalize aquaculture's environmental costs. In addition, the sustainability criteria set up for the aquaculture management alternatives is open to debate. These weaknesses affect the result of Gilbert and Janssen's analysis so that the Value of the unexploited mangrove forest is underestimated, and the value and sustainability of converting the forest into aquaculture ponds are overestimated. If applied to decision-making, the erroneous results from this partial cost-benefit analysis may have dire consequences for the mangroves and coastal communities of Pagbilao. (C) 2000 Elsevier Science B.V. All rights reserved.