Factors controlling the upper and lower limits of the intertidal distribution of two Corophium species in the Wadden Sea

Abstract

On the tidal faults of the Dutch Wadden Sea, high densities of the amphipod Corophium volutator (in silty areas) and of C. arenarium (in sandy areas) were limited to the upper parts of the intertidal zone. The upper limit was always situated close to the local level of high water at neap tides. After periods of higher- or lower-than-average water levels, the zone of C. volutator distribution had shifted upward or downward, respectively. Conversely, the lower limits of high Corophium spp. densities coincided with the upper level of high (>10 m-2) densities of adult lugworms Arenicola marina. In areas with sandy sediments (silt content