| Variations in recruitment of benthic invertebrate species with pelagic larvae, which inhabit estuaries, can be reduced by the vertical distribution of larvae. In fact, they may be located in water masses in which net transport favours retention in the vicinity of estuaries. Such a hypothesis can explain the Pectinaria koreni population stability in the western bay of Seine. The vertical distribution of P. koreni larvae is in relation to the turbulence level. When turbulence is low, strong water stratification is present, and larvae are then most abundant under the halocline (in water masses where salinity is more than 30.5). Moreover, a strong ontogenetic migration is observed : young larvae occupy the upper part of the water column and old larvae the... |
