Fishing down the food web - in other words the decrease in trophic level within exploited fish communities - is a well known problem. But what about the trophic structure of macrozoobenthos subject to fishing?Several studies so far indicated changes in the benthic community composition related to fishing. Beyond the common analyses based upon abundance and biomass data, we focus on the less studied impacts on the trophic structure of the benthic community by means of stable isotope analyses (δ15N, δ13C).The community within a recently closed area around the research platform FINO 1 (German Bight) was compared to that of the intensively fished surrounding. The density of scavengers and predators was significantly higher in the fished area, sedentary, opportunistic species predominated in the closed area. The trophic position of selected species and the general trophic structure of the benthic community were analysed comparing closed and fished areas.If the closure alters benthic community structure, it can also alter the trophic relations of the system, as effects are not restricted to the benthos, but may extend to demersal fish feeding on it - and beyond.
Helmholtz Research Programs > MARCOPOLI (2004-2008) > CO2-Coastal diversity - key species and food webs