The five large marine ecosystems investigated in the paper (The North Sea, the Barents Sea, the Baltic Sea, The North East US Continental Shelf and the Benguela Current).

New Ocean Life paper shows the fisheries efficiency in five large marine ecosystems

Sunday 28 Aug 16


Ken Haste Andersen
Professor, Head of Section
DTU Aqua
+45 35 88 33 99
In a new paper in Fish and Fisheries Ocean life researchers investigate the efficiency of fishing in large marine ecosystems in Europe, Africa and North America.  They show how it is possible to increase the fisheries yield (economic or biomass) while at the same time decreasing the impact of fishing in those systems. 

The ecosystem approach to fisheries requires the incorporation of ecological interactions when managing marine fisheries. However, the implementation of the ecosystem approach has lacked so far. In their new paper, “Efficiency of fisheries is increasing at the ecosystem level”, Nis S Jacobsen, Ken H Andersen (both Centre for Ocean Life) and Matthew Burgess (UC Santa Barbara) investigate how an ecosystem approach can be used to quantify the trade-offs between exploiting ecosystems and at the same time conserving ecosystem state. They do so by calculating the so-called ‘efficiency frontier’ in the North Sea, the Barents Sea, the Baltic Sea, the Benguela Current and the northeast US continental shelf. The efficiency frontier is a set of ecological outcomes between two indicators that have trade-offs (e.g., fisheries yield and ecological state), where neither of the two can increase without decreasing the other.  If a system is managed in such a way that one of the indicators can increase without negatively affecting the other, there is room for efficiency gains, and a possible management win-win can be achieved. 

The authors show that three of the five ecosystems have been operating close to the efficiency frontier (the two indicators being yield and ecosystem state) during the last three decades, but also that the ecosystem moved closer to the frontier, indicating that management has improved. The Baltic Sea and the northeast US continental shelf both had room for improvement in management, as both, total yield and ecosystem state, had potential for improvement. Furthermore, the authors suggest the management strategy needed to reach the efficiency frontier. 

Second, the authors calculated the economic frontier in the Baltic Sea and the North Sea by investigating the trade-off between economic rent of fisheries and ecological state. During the 2000’s both systems had moved closer to the frontier by increasing both ecological state and economic rent. 

The authors conclude that fisheries management has improved over the last couple of decades, but there is still room for further improvement, and suggest efficiency frontiers as a possible way to implement the ecosystem approach into contemporary fisheries management. 


Read the paper online by clicking here,
21 FEBRUARY 2020