Rocky Shore Samples: Bayesian Networks as a novel tool to enhance interpretability and predictive power of ecological models.

Our study site was two continuous sections of rocky shore of 10m in length at East Sands, St Andrews, Scotland (56°20'04.0"N 2°46'23.2"W). Both sites were at a tidal height of 2.9 m above chart datum. These sites were selected based on initial inspection of community structure to ensure that both macroalgae and barnacle stands were present, but were otherwise haphazardly selected from other potential sites at this height on the shore.

All sampling occurred in May 2020. Sampling only occurred during low tide time periods. Fifty haphazardly placed 50x50cm double strung quadrats were placed at each site. Grazer count (for Littorina littorea (littorinids) and Patella vulgata (limpets) were obtained for each quadrat. Percentage cover estimates for barnacles (Semibalanus balanoides and Chthamalus stellatus), macroalgae (Ascophyllum nodosum and Fucus vesiculosus) and microalgae (Biofilm) were obtained by photographing the quadrat frames using an iPhone XR. Other grazer species were extremely rare, and accounted for < 2% of grazers found.