PARENT SESSION
Contributed Oral Session 9: Marine Ecology: Disturbance; Dispersal; Recruitment
Monday, August 8, 8:00 AM - 11:30 AM, Meeting Room 519 A, Level 5, Palais des congrès de Montréal
Larval dispersal on two scales: Populations of marine invertebrates open or closed?
Sundelöf, Andreas*,1, Åberg, Per1, Airoldi, Laura2, Jonsson, Per3, 1 Department of Marine Ecology, Göteborg University, Göteborg, Sweden2 Laboratorio di Ecologia Sperimentale, Centro Interdipartimentale di Ricerca per le Scienze Ambientali, Universita' di Bologna, Ravenna, Italy3 3Department of Marine Ecology, Tjärnö Marine Biological Laboratory, Strömstad, Sweden
ABSTRACT- The ongoing debate of whether populations of marine invertebrates are mainly open or closed is waiting for a final breakthrough that can resolve the black box of larval dispersal. Hitherto, modeling exercises of larval dispersal have been simplistic and unrealistic. We demonstrate the usefulness of 2D-hydrodynamic simulations of turbulent waters to force larval dispersal in a 20 by 60 km area in the NW Adriatic Sea. A 0D-stochastic diffusion model (random walk) is contrasted with a 2D-lagrangean simulation model. With the dispersal models coupled to a demographic model of the adult populations we model the entire life cycle of a marine invertebrate limpet, Patella vulgata. The relative importance of dispersal and post-settlement processes are investigated. First, local populations may be dependent on recruitment of new individuals differentially depending on the size of the local population. Second, the regional persistence of a species may be dependent on the spatiotemporal distribution of sources and sinks. The distinction between sources and sinks is shown to vary with time and the persistence of the regional population is shown to be sensitive to particular local populations. These new results will influence the design of marine reserves and provide an efficient, although numerically intense, way to model spatially structured populations in the marine environment.
Key words: lagrangean simulation model, larval dispersal, spatial model, marine invertebrates