Ecosystem-Based Management strategies to improve aquaculture in developing countries: Case study of Marismas Nacionales

Abstract

The Ecosystem Based Management approach is an opportunity to maximize ecosystem services while promoting ecological resilience and appropriate productive activities. However, implementing this management strategy relies on acknowledging spatial interactions between economic activities and ecosystem services as well as an effective communication between scientists and decision-makers. The lack in understanding those interactions and management decisions based on limited information has led to an unsuccessful transition between artisanal and intensive aquaculture in a Wetland of International Importance (NW Mexican Pacific). In this study, we evaluated the effect of aquaculture as a driver of wetland degradation and water quality and analysed the perceptions of decision makers and scientists concerning the spatial scale of aquaculture impacts on ecosystem services.From 1997–2013, we found that herbaceous wetland and croplands have been lost while grasslands, urban areas, aquaculture and mangroves have increased. Shrimp ponds were built on natural water bodies, herbaceous wetlands and croplands. However, perturbed mangrove patches are found near aquaculture ponds, mostly downstream. Water samples were analysed and differences were found between upstream and downstream sampling sites in the concentration of DO, COD, TS, salinity, SO42-, Cl-1, CaCO3, Na, Cr, Ni and Al. Sediment analysis showed that the amount of coarse sediment such as sand and gravel diminished significantly upstream and does not reach the river mouth. Finally, perceived spatial relationship analyses showed that most academics surveyed recognized that aquaculture could have a far-reaching impact outside the immediate production area. On the other hand, more than half of the decision makers who responded did not perceive any impact and the majority of the rest considered that the impact occurred close to the ponds. The likelihood of integrated coastal management strategies being implemented depends on the close collaboration of scientists and decision makers, on their understanding of complex spatial interactions, on developing appropriate management alternatives and on incorporating science in spatial planning and decision making.