2013 EUNIS habitat map of of Bassurelle Sandbank SCI

The survey area was split into two, each was surveyed using acoustic and ground-truthing methods. Acoustic multibeam and sidescan sonar data were acquired along parallel corridors within each sampling area. Near 100% sidescan data coverage was obtained; multibeam data coverage obtained was significantly less. The location of the majority of ground-truthing stations was based on a 1 km triangular grid across the entire survey area; additional sampling stations were targeted opportunistically between the gridded stations.

The habitat map was produced using EUNIS classes obtained from PSA data and interpretations from still images, to inform the semi-automated object-based imagery analysis (OBIA). The OBIA divides the bathymetry and backscatter data into meaningful objects based on their spectral and spatial characteristics, which can then be classified using the ground-truthed data.