Effect of closed areas on distribution of fish and epibenthos

The high blue mussel catches in a fjord system in Denmark, the visible effects of dredging by resuspension of bottom sediment and the possible destruction of benthic flora and fauna have all raised concerns about the impact on the ecosystem. As a consequence, a formerly lucrative blue mussel fishing area in the fjord was closed on dredging in 1988.

This made it possible to investigate changes in the distribution of fish and benthos based on experimental fishing with trawl, set net and traps, and scuba diving during 1981-1998. The investigations showed no long-term effects of mussel dredging on the distribution of fish and epibenthic invertebrates, and the closed area appeared to have had no influence on the demersal fish and epibenthic fauna.

Factors other than mussel dredging appear to determine the observed spatial and temporal variability in the ecosystem. (C) 2000 International Council for the Exploration of the Sea.