Beauty is in the eye of the beholder: Management of Baltic cod stock requires an ecosystem approach

In a recent 'As We See It' article, Cardinale & Svedang (2011; Mar Ecol Prog Ser 425:297-301) used the example of the Eastern Baltic (EB) cod stock to argue that the concept of ecosystem regime shifts, especially the potential existence of alternative stable states (or dynamic regimes), blurs the fact that human exploitation (i.e. fishing) is the strongest impact on marine ecosys- tems. They further concluded that single-species approaches to resource management are function- ing and that ecosystem-based approaches are not necessary. We (1) argue that the recent increase in the EB cod stock is inherently uncertain, (2) discuss the critique of the regime shift concept, and (3) describe why the EB cod stock dynamics demonstrates the need for an ecosystem approach to fisheries management.

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