Rocky Reef and Sedimentary Habitats Within the Continental Shelf of the Southeastern Bay of Biscay

Abstract

Southeastern Bay of Biscay (Basque coast) seafloor characterization and benthic habitat mapping was carried out integrating data from multibeam echosounder, topographic and bathymetric LiDAR, video, and sediment and biological sampling ranging from the intertidal zone up to 100 m depth over 1,096 km(2). The area shows high geomorphologic diversity from which rocky reefs, sedimentary habitats, and mixed rock and sediment seascapes are dominant. Rocky bottoms are dominant along the shore and they reach the outer part of the continental shelf; meanwhile, sandbanks are distributed from beaches and river mouths down to muddy depths. Marine habitats along the Basque coast are related to geomorphology and hydrography. The analysis of biological and environmental data shows that wave energy, in the near-bottom, and sedimentary characteristics are the main environmental factors explaining the composition and spatial distribution of sedimentary benthic communities. Within the continental shelf, habitat suitability modeling has been applied, focusing on biological resource management. Moreover, different approaches have been carried out, especially in areas of process-driven habitat mapping, for ecosystem-based management, goods and services valuation, and marine spatial planning.