WIND-DRIVEN SETTLEMENT-PATTERNS IN THE ACORN BARNACLE SEMIBALANUS BALANOIDES

We quantified daily larval settlement of the acorn barnacle Semibalanu s balanoides in a small embayment within Narragansett Bay, Rhode Islan d, USA, to examine the hypothesis that local wind patterns influence s horeline settlement. Daily larval settlement and the accumulation of b arnacle recruits were both strongly correlated with local wind pattern s within and among years. When prevailing winds were out of the south, larval settlement was enhanced on the northern side of the bay, where as when winds were out of the north, larval settlement was enhanced on the southern side of the bay. These patterns were observed over 2 set tlement seasons and led to daily as well as interannual spatial patter ns in both larval settlement and the accumulation of barnacle recruits . The patterns of shoreline settlement appear to be caused by wind-ind uced changes in larval concentrations on different sides of the bay. W ater column larval densities were strongly correlated with daily wind patterns. Larval densities were always highest on the down-wind side o f the bay. Our data show that spatial and temporal patterns in the set tlement of benthic invertebrates can be strongly Linked to local weath er conditions through the transport of larvae by wind-driven currents.