The impact of Melinna palmata grube, a tube-building polychaete, on meiofaunal community structure in a soft-bottom subtidal habitat

Field investigations were performed in a low-energy subtidal muddy sediment in Loch Creran, a sea-loch on the west coast of Scotland where the impact of Melinna palmata, a tube-building polychaete, on the meiofaunal community structure was assessed. This polychaete was found in high densities and forms prominent faecal casts on the sediment surface. Samples were retrieved from the casts, the feeding area of the polychaete and from an unaffected control area. The number of nematodes, the dominant taxon, did not vary significantly between areas. Of the five most abundant nematode species one was significantly more abundant in the cast area. Diversity and trophic structure of the nematode component of the meiofauna was very similar in all three areas. Copepods were more than twice as abundant in background sediments as in faecal mounds and feeding areas; however, Longipedia spp. were more abundant in the cast areas. For the copepods these findings support models which state that natural disturbances create a mosaic of patches that have different species compositions depending on their states of recovery. © 1990.