Showing papers by "Robert R. Twilley published in 2002"

Hurricane Mitch: integrative management and rehabilitation of mangrove resources to develop sustainable shrimp mariculture in the Gulf of Fonseca, Honduras

Abstract: Any use of trade, product, or firm names is for descriptive purposes only and does not imply endorsement by the U.S. Government. Hurricane Mitch: integrative management and rehabilitation of mangrove resources to develop sustainable shrimp mariculture in the Gulf of Fonseca, Honduras: USGS Open File Report 03-177, 120 p. One of the major difficulties in developing coastal management plans in tropical regions of the world has been the conflict between developing and expanding shrimp mariculture and the conservation and management of mangrove resources. The conflict arises due to the use of mangrove forest areas to establish shrimp farms, a practice that has resulted in significant losses of mangrove forests in different parts of the world during the last 25 years. Due to an increasing awareness of the potential environmental impacts that shrimp mariculture practices have on the environment, the shrimp industry 4 has began to develop best management practices in cooperation with government agencies, financial institutions, and NGOs. One of these practices include the nonconstruction of shrimp farms in mangrove dominated coastal zones (Stanley, 2000; Boyd and others, in press). The analysis of production trends of shrimp ponds constructed in mangrove areas has shown that these areas are the least desirable to establish shrimp operations due to high concentrations of total sulfur and organic matter that negatively affect shrimp growth and increase maintenance costs. Although this practice will certainly contribute to the conservation of mangrove forest, it is still not clear what will be the impact of wastewater from shrimp mariculture on ambient water quality of adjacent estuarine and coastal waters. The purpose of this study was to evaluate how the rehabilitation of coastal resources damaged by Hurricane Mitch could be integrated into ecological processes of mangrove ecosystems with management practices of shrimp pond mariculture in the Gulf of Fonseca. We first estimated the total area of mangrove resources for the entire Gulf of Fonseca, including coastal areas in Honduras, El Salvador, and Nicaragua, using remote sensing techniques. Mangrove forest and shrimp pond aerial extension and spatial distribution were determined in Honduras, particularly in the southern region of the Gulf of Fonseca, where most of the shrimp industry is located. We also estimated temporal changes in mangrove and shrimp pond cover and analyzed long term data of water quality variables available for the region to understand current levels of fertility in coastal waters. Similarly, we determine what variables control mangrove …