查看文章

The suspension-feeding gastropod Crepipatella dilatata occurs in estuaries in southern Chile that experience considerable fluctuations in salinity, driven by tidal and atmospheric forces. In the Quempillén estuary salinities as low as 9psu may occur after severe rainstorms, and persist for several hours. In this study salinity was the major factor influencing the clearance rate of C. dilatata. At salinities below 20psu, filtration ceased, whereas at high salinities (>22psu) mean clearance rate was 0.24lh⁻¹ standard animal⁻¹ (S.D. 0.18) for actively filtering individuals. This was confirmed by laboratory experiments under controlled conditions. Endoscopic observations were consistent with measurements of clearance rate, and showed that at salinity 25–30psu the rate of transport along the gill filaments of particulate material embedded in mucus was 759μms⁻¹ (S.D. 480), but particle transport ceased at and below salinity …