The Fisheries Committee hosted a public hearing on Maximum Sustainable Yield (MSY) earlier this week. A number of experts within the field where invited to discuss both the scientific and practical aspects of implementing MSY in fisheries management within EU fisheries.
The public hearing aimed at clarifying the MSY concept and to give members of the committee and MEPs a better understanding of the underlying science. Since the agreement of the new Common Fisheries Policy (CFP), there has been much debate about how to implement MSY and how far above MSY to set biomass targets.
One of the pioneers in fisheries modelling, Sidney Holt, stressed that fisheries are already selective, and that one of the most important factors in fisheries management is not selectivity itself but economics. Holt stressed that the market “dictates” the fishery to a much greater extent than one would want to admit. Holt advised the Parliament to address not only the dynamics of the fish stock but also the economic dynamics and the collective desirable targets as this would allow for both sustainable and economically stable fisheries.
Article 2.2 in the CFP (EU)1380/2013) states: “The CFP shall apply the precautionary approach to fisheries management, and shall aim to ensure that exploitation of living marine biological resources restores and maintains populations of harvested species above levels which can produce the maximum sustainable yield”.
Rainer Froese, from GEOMAR, highlighted a number of pitfalls associated with MSY as a management tool which the Fisheries Committee, Council and Parliament should be aware of;
- Using MSY or Fmsy as a target. As reproduction and growth fluctuates naturally within a stock, there is a 50% chance that estimates of MSY or Fmsy are set too high. Avoiding overages of MSY/Fmsy can be accomplished by targeting a precautionary fraction of MSY of at least F0.8.
- Using MSY or Fmsy for all stocks simultaneously. Forage fish play a crucial role within the food web, and if they are also targeted then they should be fished even less eg. At F0.5 and;
- Catching fish before they have a chance to grow and reproduce. Froese argued that gear selectivity shall be set so that the mean length of catch is near 2/3 of the targeted fish’s maximum length as the growth rate is generally highest at that length. Froese noted that fish mature at 1/3 to 2/3 of maximum length, and that for any given F catches are highest of fish near 2/3 of their maximum length.
Samuel Rauch from NOAA gave some food for taught, presenting some practical examples of how MSY is applied within fisheries management in the USA. In short, USA has a flexible management system where the fishermen are heavily involved and where MSY is used as an overfishing limit and not a fishing target. The system tends to manage fisheries through Fmsy as it is hard to manage Bmsy, thus Bmsy is the target and managed through Fmsy manipulations.
During one of the last presentations, Björn Stockhausen from Seas At Risk highlighted a general failure to adhere to CFP reforms, namely that the objective to achieve stock levels above Bmsy has not been adhered to or supported by measures in a number of new management plans such as the Baltic Multiannual Plan. Stockhausen kindly pointed out that it is the Fisheries Committee’s mission to “defend” the CFP and make sure CFP objectives are met. The Commission responded to Stockhausen’s presentation with the intervention that Bmsy is an aspirational objective of the new CFP, and that the operational management should be based on Fmsy for EU fisheries.