Community structure and production of the macrobenthic infauna in relation to the microdistribution of trawling effort

The longer term effects of beam trawl fisheries depend on the benthic species composition and the life history characteristics. Beam trawling may have caused a shift in the benthic community from low-productive, long-lived species to high-productive, short-lived species. The effects may be inferred from comparisons of areas under different levels of fishing disturbance. Craeymeersch et al. (2000) focused on two subareas on the Dutch Continental Shelf. The authors indeed found a significant difference in species composition betweenintensively fished and less heavily fished areas but the found relationship might be largely correlative. It has been suggested that the scale at which the study was done was too small. A re-analysis of the data on a larger scale did not result in a significant relationship between species composition and fishing effort. There seems to be no straight relationship between fishing effort and infaunal productivity. It is concluded that this not necessarily points to the non-existence of such relationship but to the need of more detailed analyses taking into account the temporal and spatial dynamics of fishermen, target species and benthic species.