How Pervasive is "Fishing Down Marine Food Webs"?

In their report (1), and in an earlier paper (2), D. Pauly et al. draw global conclusions about the effects of fishing on world fish stocks with the use of research data fitted to Ecopath models at different sites through the world's oceans, integrated with data on global fishery landings collected by the Food and Agricultural Organization of the United Nations (FAO). Although Pauly et al. are to be congratulated for giving this important issue high profile, they greatly oversimplify the situation with their hypothesis and may have misinterpreted the FAO statistics. We do not disagree that a general decline in mean trophic level of marine landings is likely to have occurred in many regions, but we are not convinced that the explanation is solely a result of “fishing down the food web” or that the analysis of the FAO data, as undertaken by Pauly et al., substantiates such a thesis.