Abstract
Food resources of the dense patches of suspension feeding bivalves, including Arcuatula senhousia , have been considered as transportation of allochthonous organic matter derived from primary producers on the Midori River tidal flats. However, there are no direct evidence of primary production of microalgae in this area. In this study we estimated secondary production of A. senhousia in addition to primary production of phytoplankton and microphytobenthos on the Midori River tidal flats, and discussed quantitative evaluation of their feeding activity on the habitat. The secondary production of A. senhousia was 1 .6 ± 0.7 g C m–2 d–1, contrasting with the total primary production of phytoplankton (0.05 ± 0.04 g C m–2 d–1) and microphytobenthos (0.31 ± 0.33 g C m–2 d–1). If we assumed that growth efficiency of A. senhousia was 19%, their daily feeding rate reached 7.8 g C m–2 d–1, which was approximately 23 times higher than that of the primary productivity. Thus, the dense patches of A. senhousia should consume primary producers in 23 times wider area than that of their habitat area.
https://ror.org/00b7yvh50 
