Résumé
We used the Lagrangian dispersal modelling tool Ichthyop (Lett et al. 2008) to track particles representing numerical larvae passively transported by current velocity fields in the Tropical Southwestern Atlantic.To release and recruit particles we selected estuaries along the coast with a clear connection to sea. Then a polygon was defined in the 2x2 cells (a cell is 1/18°) closest to the river mouth in the velocity field grid. Simulations were performed monthly from January 2009 to December 2016, totalling 96 runs. In each simulation, 1000 particles were randomly released within each polygon, from the surface to the seafloor. We adopted a community-based approach by simulating particle dispersal across a continuous range of Planktonic Larval Durations (PLDs). To achieve this, the position of each released particle was tracked for 60 days, and locations were recorded daily, so that each daily record represents organisms with a PLD equal to the number of days since release. PLDs were classified through hierarchical clustering based on the similarity of their connectivity patterns, resulting in three classes. The Short PLD class (1–5 days) represents sessile benthic invertebrates such as corals, sponges, polychaetes, and bryozoans; the Medium PLD class (6–20 days) represents many invertebrates typical of estuarine environments, including crabs, shrimps, bivalves, gastropods, and the medusoid stage of hydrozoans; the Long PLD class (21–60 days) represents estuarine fish, along with certain crustaceans and echinoderms.