Inferring changes in North Sea benthos from fish stomach analysis

Abstract

In this study we formulated a priori hypotheses for the changes in the benthos that would be expected as a result of the direct impacts of trawl fisheries. These were tested using a data set comprising stomach contents for dab Limanda limanda collected in March and August in the early 1950s and a matched sample from 1996-97. Changes in samples taken in August were consistent with the hypothesised effects of fishing, with an increased prevalence of scavengers and decreased occurrence of sedentary polychaetes in the diet. There were also marked differences between the 1950s and 1996-97 for March samples due to the high prevalence of fish remains in the contemporary samples. While our results must be treated with caution, they are consistent with the hypothesis that there have been widespread long term changes in benthic communities due to fishing.