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Little justification for MSY approach

13 May 2013
Ian Boyd said that MSY should be regarded as a limit, not a target. Credit: Macieklew/CC-BY-SA-2.5

Ian Boyd said that MSY should be regarded as a limit, not a target. Credit: Macieklew/CC-BY-SA-2.5

Andrew Martin looks at the MSY approach to fishing.

Fishing to maximum sustainable yield (MSY), which is an integral part of the EU’s revised Common Fisheries Policy (CFP), has little justification, according to Ian Boyd, Defra’s chief scientific adviser.

“It is at too high a level to conserve fish stocks for the future,” he said. “If MSY is to be used then it should be regarded as a limit, not a target.

“If we want a fishery in 20-30 years’ time, we may have to accept some reduction [in the catch] below this level. Otherwise there is an inevitability that stocks will fail. We’re aiming at an uncertain target [with MSY]; overshoot is a problem. That’s what we have been doing consistently and it leads to stock reduction.”

Fishing to MSY also ignores fundamental aspects of the ecosystem such as the need to leave enough fish in the sea for other parts of the food chain including mammals and seabirds, he added.

Professor Boyd said there was clear evidence of chronic overfishing of commercial stocks in the North Sea since 1980. Advice on fishing levels was being heeded by management, he said, “but actual catches were somewhat different”.

In addition, Professor Boyd said that the current single species system, as used by ICES (International Council for the Exploration of the Sea) in setting EU quotas, “was no longer fit for purpose. The new system has to be fit for purpose.”

Dr Boyd, Buckland Professor for 2012/13, was giving one of the Buckland Foundation’s special lectures at Fishmongers’ Hall in London, earlier this year. He spoke after Sidney Holt, the current professor, and the theme of both lectures was: ‘Why, or why not, MSY? Contemporary thoughts on the rational management of fisheries’.

Both speakers agreed that fishing in European waters should be reduced. And although painful to start with this would eventually benefit fishermen in that there would be more profit for those left in the industry.

Professor Holt was even more forthright in his lecture. “Fisheries have to be managed so that they are profitable otherwise fishermen won’t go out to fish,” he said. “And fishing for MSY was not the best way to achieve this objective.

“Setting TACs [total allowable catches] is the worst possible way to manage a fishery. You have to manage the input [to the fishery], which depends on recruitment, not the output.”

It was pointed out during one of the discussion sessions that it was easier to measure mortality, in terms of catches, than the actual biomass of a stock. However, it was also pointed out that neither fisheries scientists nor fishermen themselves knew how much fish was being caught in the North Sea as half of it was thrown away without being recorded (discards).

Although fishing for MSY is not the ideal solution to reduce overfishing, delegates attending the lectures regarded it as being a step in the right direction. Speaking after the lectures, Colin Bannister, a trustee of the Buckland Foundation said: “MSY is a step on the way to the profitability that Professor Holt is seeking. There is light at the end of the tunnel.”

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Ian Boyd said that MSY should be regarded as a limit, not a target. Credit: Macieklew/CC-BY-SA-2.5

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