Full article courtesy of Mike Urch, SeafoodSource contributing editor
29 March, 2013 -
Fisheries should be managed so that they are profitable, otherwise fishermen won’t go out to fish. And fishing for maximum sustainable yield (MSY), which is a main criterion of the EU’s revised Common Fisheries Policy (CFP), is not the best way to achieve this objective.
So said Professor Sidney Holt when giving one of the Buckland Foundation’s annual lectures in March. “The value of the catch has to be more than the cost of catching it. Setting TACs (total allowable catches) is the worst possible way to manage a fishery.
“You don’t just use the brakes when driving a car. You have to manage the input not the output, which depends on recruitment [to the fishery].” The recruitment number can be the most variable, Holt said. “It can change by a factor of 100 year to year.”
Regarded as one of the founders of fishery science, Holt was speaking on the theme, “Why, or why not, maximum sustainable yield (MSY)? Contemporary thoughts on the rational management of fisheries” at Fishmongers’ Hall in London.
Although MSY forms a major constituent of the revisions now being sought for the CFP, the concept had first been introduced by the U.S. government at a conference in 1949 as a management objective for stopping Japanese fishing vessels coming into its waters to catch salmon.
There were no territorial waters in those days, Holt said, but added that the U.S. government sought to claim that it was fully utilizing the resources within what became its 200-mile limit or exclusive economic zone.
Maximizing yields using surplus production models is an unscientific method of managing fish populations, according to Holt. “You can’t use it to take account of selectivity. You’re catching too many fish when they’re young. This is the issue.
“You’ve got to look at the relationship between growth and death. How much more [death] is caused by fishing than nature?”
Ian Boyd, who preceded Holt as Buckland Professor for 2012/13, and spoke after him, agreed that there is little justification for the maximization of yield approach.
“If MSY is to be used then make it a limit not a target,” said Boyd.
Boyd went on to say that in his view fishing for 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. To do this means reducing the proportion of the fish stocks that is harvested.
Both speakers agreed that fishing in European waters should be reduced. Less fishing effort would mean more profit for those left in the fishery, and it would also provide a better balance between the components of the food chain that are harvested by fishermen, mammals and birds.
Determining the reduction in fishing effort required was difficult. There was a suggestion from a delegate that to achieve maximum economic yield in a fishery that was completely unregulated would mean reducing fishing effort by a massive 80 percent.
This size of reduction would not be necessary for fisheries regulated by the current CFP. However, because of the practice of discarding, scientists — and therefore fisheries ministers — didn’t know how much fish was already being harvested, which would be necessary before a reduction in fishing effort could take place. Said one delegate: “We don’t know what is caught in the North Sea as 45 percent of the total catch is thrown away (discards) without being recorded.”
A discard ban — another objective of the revised CFP — was much in favor with delegates, although there were very few fishermen in the audience and not all are thought to agree with this approach. It was mentioned that there was a better understanding of fisheries management in the Netherlands because fishermen and scientists work better together there.
As Colin Bannister, a trustee of the Buckland Foundation, put it in his summing up of the proceedings: ‘Fisherman have a great deal of knowledge that is worth tapping into.
“The ideals of fisheries management are relatively simple,” Bannister told delegates at the beginning of the proceedings. “But the practice is actually very difficult.” However, as the proceedings concluded he did think there was “light at the end of the tunnel.”
Speaking afterwards he said: “Scientific advice for the crisis stocks is now aiming to establish a fishing rate rather than a stock biomass,” said Bannister. “Fishing rates are now falling in the most critical fisheries, and are closer to MSY, which even though not the ideal is nevertheless a step on the way to the profitability that [Professor Holt] is seeking.”