Spatial patterns in planktonic cnidarian distribution in the western boundary current system of the tropical South Atlantic Ocean

• Published in: Journal of Plankton Research
• Main Authors: Tosetto, Everton Giachini, Bertrand, Arnaud, Neumann-Leitao, Sigrid, da Silva, Alex Costa, Nogueira Junior, Miodeli
• Other Authors: MARine Biodiversity Exploitation and Conservation (UMR MARBEC), Institut de Recherche pour le Développement (IRD)-Institut Français de Recherche pour l'Exploitation de la Mer (IFREMER)-Université de Montpellier (UM)-Centre National de la Recherche Scientifique (CNRS)
• Format: Article in Journal/Newspaper
• Language: English
• Published: HAL CCSD 2021
• Subjects: circulation; medusae; transition; adriatic sea; vertical-distribution; water masses; North Brazil Undercurrent; Northeast Brazil; epipelagic siphonophores; Fernando de Noronha chain; gelatinous zooplankton community; pelagic cnidarians; scale distribution; siphonophore assemblages; siphonophores; South Equatorial Current; tropical Atlantic Ocean; [SDE.BE]Environmental Sciences/Biodiversity and Ecology; [SDE.MCG]Environmental Sciences/Global Changes; South Atlantic Ocean
• Online Access: https://hal.umontpellier.fr/hal-03415697; https://doi.org/10.1093/plankt/fbaa066

WOS:000642325100013 International audience In marine western boundary systems, strong currents flowing coastward spread oceanic water masses over the continental shelves. Here we propose to test the hypothesis according to which oceanic cnidarian species may dominate western boundary system regions even in coastal waters. For that purpose we use a set of data collected above the shelf, slope and around oceanic seamounts and islands in the Western Tropical South Atlantic. Samples were acquired with a plankton net with 300 mu m mesh size over 34 stations during an oceanographic cruise carried out in October 2015. Results reveal a diverse cnidarian assemblage in the area, extending the known distribution of many species. In addition, the Fernando de Noronha Chain and most of the narrow continental shelf presented a typical oceanic cnidarian community, dominated by holoplanktonic siphonophores. In this western boundary system, this condition was likely driven by the strong currents, which carry the oceanic tropical water and associated planktonic fauna toward the coast. A specific area with reduced influence of oceanic currents presented typical coastal species. The pattern we observed with the dominance of oceanic plankton communities up to coastal areas may be typical in western boundary systems characterized by a narrow continental shelf.