Assembling data for coastal and marine spatial planning in the Western Indian Ocean

Restoring, maintaining and conserving the ecological integrity of the Agulhas Somali Current Large Marine Ecosystem (Figure 1) while ensuring optimal and sustainable utilization of the resources has been identified as a priority (Obura et al., 2012), especially with regard to the development of policy for the establishment of transboundary Marine Protected Areas (MPAs). This task requires knowledge of the spatial distribution of the physical and biological patterns and processes than sustain marine biodiversity in the region (Lombard et al. 2007; Sink and Attwood 2008). Understanding the spatial characteristics of the large and complex pelagic realm is the foundation for assessing pelagic biodiversity and further planning and implementing a representative system of MPAs in the Western Indian Ocean region. Therefore, the aim of this study was to map and describe the pelagic bioregions of the ASCLME area of interest. The intended outcome was a set of pelagic bioregions that will underpin a spatial framework to support future coastal and marine spatial planning. Bioregionalisation is a process that aims to classify a geographic area into broad scale, biologically meaningful units, based on a set of physical and biological variables. For example, variations in depth, temperature or nutrient availability across space and time define different habitat types. In turn, these habitats are assumed to be correlated with different biological communities. In this report, we identify a spatially nested system of bioregions grouped into 3 agregative levels.