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Towing gears are known to produce several kinds of effects on benthic ecosystems. As small organisms and benthic species with faster growth rates and shorter life histories can withstand the fishing mortality and benefit from reduced competition or predation, trawl fishing can enhance their proliferation. Thus, trawl fishing can lead to biomass loss and production increase, since smaller specimens are more productive than bigger ones. In the present study we evaluate the effects, if any, of trawling on benthic crustacean macrofaunal production rates. Sampling was carried out in two neighbouring sites in the central Adriatic Sea (central Mediterranean), one affected by fishing activity and one not. Production and production/biomass (P/B) ratio of 13 species of peracarid and eucarid crustaceans were estimated using the Hynes size-frequency method. Estimates measured at both sites were compared in order to test the hypothesis that higher production and P/B values should occur in the fished area rather than in the unfished one. Our results indicated that the effects on the species are more complex than expected in regard to this hypothesis, and that they depend on the ecological and behavioural characteristics of the selected species. [ABSTRACT FROM AUTHOR]

Macrobenthic communities in a commercial fishing ground (middle Adriatic Sea) exploited by otter trawling were compared with communities living in an area closed to fishing for over 10 years located near a gas platform. Our data highlighted significant differences in macrofaunal community structure between the two areas. In addition, the macrofaunal communities in the fished area displayed evidence of a higher level of stress compared with the other one. Several taxa reported in the literature as being sensitive to trawling (e.g., Ebalia tuberosa, Callianassa subterranea) were markedly more abundant in the area not affected by fishing. Macrofaunal community analysis using the index of multivariate dispersion and κ-dominance curves provided evidence of stress in the fished area; however, it is not possible to predict whether the patterns observed will remain consistent over time based on only two temporal replicates. It is likely that the magnitude of the macrofaunal community response to fishing changes during the year according to season and fishing effort. [ABSTRACT FROM AUTHOR]