Diversidad del Banco Patria, Mar del Plata, Argentina

Abstract

Census were carried out by SCUBA diving at the 26–32m depth at Banco Patria, 38°07´S – 57°21´W, in April and May (austral fall) and December 2019 and January 2020 and 2022 (austral summer). The reef mainly comprised large continuous flat platforms, with presence of horizontal and low ledges. According with the different surface orientations three microhabitats were considered: terraces (horizontal rocky floor on flat platforms), ledges borders (vertex of the terraces where floor change abruptly of inclination conforming narrow vertical substrata) and ceiling (swallowed and overhang substrata). Quantitative assessment of most conspicuous macrobenthic organisms identified in the three different microhabitats was evaluated using the video-transects at 0.45 m above the substrate on the starboard side. The recorded images were analyzed by playing back the video and viewing on a screen with five points arranged. The video tapes were stopped at set intervals. To provide good estimates of total cover 25–50 points were counted in each transect. Any organism lying beneath each of the five points was identified and classified to the lowest possible taxonomic level. For each organism, percentage cover was estimated by dividing the number of points at which that taxon was recorded by the total number of data points, and multiplying by 100.