Testing methods to support management decisions in coralligenous and cave environments. A case study at Portofino MPA

Baseline data on the distribution, condition and extent of coralligenous and cave bioconcretions is one of the main requirements of the European Marine Strategy Framework Directive (MSFD) necessary to assess the achievement of a Good Environmental Status (GES) by 2020. In this study the potential of remote sensing and distribution modelling techniques to map, measure descriptors and choose indicators were tested, that could provide standard methods for the assessment of the health status and assist in monitoring activities. It is demonstrated how, by combining different methodologies, it is possible to map the distribution of the bioconcretions with acceptable accuracy and to discriminate the main habitat types and facies. In addition, zonal statistical analysis revealed that fishing activities primarily coincide with areas of high coverage of the bioconcretions. Results demonstrate that the presented methodology is a valuable simple tool to assess several MSFD descriptors and indicators, and could strengthen management efficiency when making informed, ecologically relevant decisions. •Our multi-approach method maps and models the distribution of coralligenous and caves.•These methods allow the mapping and prediction at a fine scale for the first time.•Slope was identified as the determining factor in the distribution.•We ascertained the limits of the methods and suggested possible improvements.•Results demonstrated the potential of the approach to support MSFD implementation.