Benthic species diversity and sediment composition: Comment on Compton et al. (2008)

Compton et al. (2008; Mar Ecol Prog Ser 373:25�35) presented data on the number of bivalve species encountered in small core samples (0.02 m 2 ) taken in various tidal flat areas, and they used these numbers to draw conclusions on relationships between sediment type and local species richness. We argue that their samples were too small, when used on their own, to yield realistic estimates of macrozoobenthic diversity. Small samples represent merely those few spe- cies that usually occur in high numerical densities. Only 2 of the ~10 bivalve species commonly found on European tidal flats belong to this group.