Assessing the short‐term stability of spatial patterns of macrobenthos in a dynamic estuarine system

Recent studies of macrofauna on sandflats have emphasized postsettlement dispersal, particularly associated with sediment bedload transport. This study investigated the short-term (3 weeks) stability in spatial patterns of eight common, potentially mobile, near-surface macrofaunal species inhabiting a 4,000-m2 area of intertidal sandflat. Over this period, wind conditions reworked the sediment to a depth of 3 cm, thus generating sediment and animal transport. Movement and changes in spatial arrangement of juvenile M’acomona Miana and Paphies australis demonstrated the need to consider postsettlement dispersal in survivorship and experimental studies and to conduct such studies at a relevant scale. However, the majority of the species exhibited stability of spatial pattern, even when undergoing movement and changes in mean density. This finding suggests that biological interactions and organismhabitat relationships are important processes even in habitats where the sediment and organisms are mobile.

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