Addressing a gap in the Water Framework Directive implementation: Rocky shores assessment based on benthic macroinvertebrates

•Rocky shore macroinvertebrate communities were assessed along disturbance gradients.•Indices and models were tested along gradients, and compared to MarMAT assessment.•The most efficient indices were combined into a WFD compliant multimetric index.•The multimetric index was able to capture differences across the gradients.•Results were validated using independent data.