In situ feeding and absorption responses of sea scallops Placopecten magellanicus (Gmelin) to storm-induced changes in the quantity and composition of the seston

摘要: Time-series of hourly clearance, ingestion and absorption rates efficiency were measured over 48 h for adult sea scallops (Placopecten magellanicus) held in situ a coastal embayment Nova Scotia, Canada, during wind-induced resuspension event. Temporal variations oceanographic variables, seston quantity composition (organic matter, organic carbon, nitrogen, chlorophyll a, inorganic particle size spectra) monitored the study with moored instruments water sampling. Resuspension bottom materials storm resulted large changes amount (1 to 30 mg l−1 total particulate matter) nutritional quality (25 50% content) seston. High sedimentation after accelerated by flocculation, resulting rapid settling resuspended particles an increase quality. Observed short-term (hourly) fluctuations clearance rate not related storm- or tide-induced characteristics but directly flow velocity. Significantly lower observed at relatively low ( 9 cm s−1) speeds. The overall reduction from decreased food availability. Hourly (AE) measurements closely (total organic, C N AE declined exponentially decreasing Reductions event offset increased rate, no significant C, sampling period. As matter was balanced availability, any physiological regulation acquisition (i.e. regulation) would have been irrelevant maintaining intake constant.