Vertical and areal distribution of foraminiferal abundance and biomass in microhabitats around inhabited tubes of marine echiurids

Three examples of microhabitats of foraminifera around inhabited macrofaunal tubes ( Echiurus echiurus) from the German Bight are given. Compared to ambient sediments, abundances and biomass of foraminifera were up to 3 times higher within the tube. Bacterial abundances were about 2 times higher and bacterial biomass was up to 5 times higher within the tube. Data suggest that tubes and burrows provide microhabitats with increased food concentrations and foraminiferal abundances.