Print Email Facebook Twitter Transport of larvae and detritus across the surf zone of a steep reflective pocket beach Title Transport of larvae and detritus across the surf zone of a steep reflective pocket beach Author Shanks, A.L. MacMahan, J. Morgan, S.G. Reniers, A.J.H.M. Jarvis, M. Brown, J. Fujimura, A. Griesemer, C. Faculty Civil Engineering and Geosciences Department Hydraulic Engineering Date 2015-05-28 Abstract Larvae of many intertidal species develop offshore and must cross the surf zone to complete their onshore migration to adult habitats. Depending on hydrodynamics, the surf zone may limit this migration, especially on reflective rocky shores. As a logistically tractable analog of a rocky shore environment, we carried out a comprehensive biological and physical study of the hydrodynamics of a steep reflective sandy beach. Holoplankton and precompetent larval invertebrates were much less abundant within the surf zone than offshore, and their concentrations inside and outside the surf zone were not significantly correlated, suggesting that they were not entering the surf zone. Persistent offshore flow throughout the water column at the outer edge of the surf zone may prevent these organisms from entering the surf zone. In contrast, the concentrations of detritus and a competent larval invertebrate (i.e. cyprids), while also not significantly correlated with concentrations offshore, were frequently more concentrated in the surf zone than offshore. Within the surf zone, the concentration of detritus was significantly correlated with concentrations of competent larval invertebrates (barnacles, gastropods, polychaetes, and bopyrid amphipod) and organisms that may be associated with detritus (amphipods and harpacticoid copepods). These concentrations were significantly negatively correlated with average daily wave height. We hypothesize that detritus and larvae enter the surf zone near the bottom during calm wave conditions by a process of near-bottom streaming. Near-bottom streaming is associated with all surf zones and may be a general mechanism for onshore transport of larvae close to the coast. Subject streamingcypridscompetent larvaeprecompetent larvaedetritusreflective beachcross-shore exchange To reference this document use: http://resolver.tudelft.nl/uuid:7f632aae-a9e9-4139-8674-7931bdc769b3 Publisher Inter-Research ISSN 0171-8630 Source https://doi.org/10.3354/meps11223 Source Marine Ecology Progress Series, 528, 2015 Part of collection Institutional Repository Document type journal article Rights © 2015 Inter-Research Files PDF Reniers_2015.pdf 1.62 MB Close viewer /islandora/object/uuid:7f632aae-a9e9-4139-8674-7931bdc769b3/datastream/OBJ/view