Marine biodiversity from south coast of Sagres (South of Portugal-Algarve): identification and characterization of biotopes

Under the MeshAtlantic project (2010-2013) the habitat of an area off the south coast of Portugal (Sagres) was classified. The biological data was gathered from surveys carried out during 2012. Stratified sampling by depth and bottom substrate was performed using underwater visual census, Van Veen grab and beam trawl to estimate fauna densities and quadrate method to estimate macroalgae coverage. Additional and significant data was obtained from image analysis of video records collected during Remote Operated Vehicle (ROV) surveys carried out under the UALG/CCMAR programme or from strict cooperation with the NGO OCEANA. Both these surveys began with a previous acoustic mapping of the seabed by means of Side Scan Sonar and Multi-beam, followed by sediment type classification and ground truthing validation using Van Veen grab sampling.