Opitz, Dylan G.

A nearshore ridge complex (NRC) sits less than 250 m from the coast of Pompano Beach in Southeast Florida, and the varied bottom types within this complex may represent critical habitat for benthic mollusks. In order to document the diversity of mollusks within the NRC, SCUBA-based roving surveys were conducted between 2011 and 2019. Between 2021 and 2022, sediment samples were also collected from each of the bottom types to study mollusk diversity patterns. This combination of survey methods resulted in the identification of 325 species of hard-shelled mollusks, representing 103 families and 4 classes. To test for differences in community structure between bottom types, relative abundance data from the sediment samples was used for multivariate analyses including NMDS ordination, ANOSIM, and hierarchical cluster analysis. Results indicated statistically significant differences in mollusk species composition between NRC bottom types.