Late Holocene and Living Coral Composition of Pompano Ridge, FL

To determine the taxonomic composition of the late Holocene coral assemblages, surveys were conducted along 16 shore-parallel, line-intercept transects (60-m long) distributed haphazardly across the full extent of the coral rubble zone as determined by Self Contained Underwater Breathing Apparatus (SCUBA)-based ground-truthing and examination of high-resolution bathymetric data. Surficial coral rubble and dead massive colonies encountered every 5 centimeters (cm) were identified to the lowest taxonomic level recognizable without physically breaking them apart or removing algal and other encrusting overgrowths. Sub-surface coral rubble was also collected from 50-cm diameter pits excavated at a random point along each transect. Coral fragments were removed from each pit until a 2-liter mesh bag was filled (pit depths between 30 and 60 cm). Coral rubble from pit samples was also identified to the lowest taxonomic level and then pooled with data obtained from the line-point intercept transects. To determine how modern assemblages at our study site compare with the late Holocene assemblages within the study area at Pompano Ridge, live coral abundance data was collected along the same 16 transects in the summer of 2018 and the fall of 2019. For each transect, all living corals larger than 4 cm within a 1-m wide belt were identified to the species level and counted by SCUBA divers.