The scientific basis for the current “reference points” used for New England groundfish management has recently been questioned by respected scientists, industry members, and elected officials.
The largest organization representing groundfishermen in New England, and the mayor of the nation’s most profitable seaport, have asked the New England Fishery Management Council to reconsider the calculation and use of the current reference points.
Because this issue is highly technical and development of the current reference points are the result of a unique history, Saving Seafood has undertaken this analysis to shed some light on the background behind these requests for reconsideration.
by Sarah Hanselman and Bob Vanasse
WASHINGTON (SavingSeafood) January 30, 2013 — In a January 7, 2013 op-ed (“The end of ‘overfishing’?”) in the New Bedford Standard-Times, Dr. Brian Rothschild, dean emeritus and current professor at the University of Massachusetts School for Marine Science and Technology, pointed out that current fisheries management strategies for New England fisheries are “based on an arbitrarily selected biological reference point, and we have relatively little idea how close the real fishery is to the arbitrarily selected reference point.”
Reference points include fishing mortality values chosen by management bodies, which, if exceeded, indicate that overfishing has occurred in a population.
On January 17, 2013, the Northeast Seafood Coalition (NSC) wrote to the New England Fishery Management Council (NEFMC) raising questions about the reference points currently used in groundfish science and management. They suggested that alternative reference points are available and should be evaluated. Yesterday, New Bedford Mayor Jon Mitchell wrote to the NEFMC with five requests, including asking that the “Council reconsider the current reference points for all groundfish stocks” in accordance with the request made by the NSC.
National Standard One of the Magnuson-Stevens Act requires that fisheries management end or prevent overfishing on all fish stocks. To ensure compliance with this standard, the National Standard guidelines require scientists to estimate a management target that results in the Maximum Sustainable Yield (MSY). This target, known as Fmsy, is the level of fishing mortality that allows for Maximum Sustainable Yield (MSY). When a direct estimate of Fmsy cannot be made, a proxy for Fmsy must be determined. It is important to understand that FMSY is only a management target, and that yield (catch) both above and below MSY can be sustainable.
Before 2002, Fmsy was directly estimated on a stock specific basis for about 2/3 of groundfish stocks. But, after exploring a wide range of direct estimates for FMSY, the Working Group concluded FMSY could not be reliably estimated for most groundfish stocks. Thus, In 2002, the Working Group on Re-Evaluation of Biological Reference Points for New England Groundfish began to replace direct estimates of Fmsy with “proxy” values. Specifically, the Working Group chose an approach based on Maximum Spawning Potential (MSP), a theoretical measure of a stock’s potential population without exposure to fishing pressure. The Working Group chose 40% MSP as the best proxy measurement for Fmsy. F40%msp suggests an associated level of fishing pressure that would reduce the stock to 40% of a theoretically unfished population. Though some studies disagree that stock can be theoretically estimated using MSP.
By 2007, the Groundfish Assessment Review Meeting (GARM III) Working Group transitioned all New England groundfish stocks from direct estimates of FMSY to proxy reference points, based on the 2002 Working Group report.
Although a variety of approaches are available to estimate Fmsy and alternative proxies, the current system has adopted F40%msp proxy as the default reference point for most groundfish stocks. This has been criticized by some industry observers, non-Federal Government scientists, and at least one NEFMC member, who argue that a range of alternatives should be presented to the NEFMC for comparison and deliberation.
Since 2002, the FMSY estimate or the proxy has been revisited at each benchmark. As a result, several stocks now use a direct estimate of FMSY.
The NSC also raised questions about the appropriateness of using F40%mp as a reference point for all groundfish stocks. They suggested that if it is determined that an MSP-based proxy is appropriate for a particular stock, the percentage should be evaluated and optimized based on the characteristics of that stock and the NEFMC’s management objectives. The NSC argued that the F40%msp reference point is arbitrary and antiquated.
According to the scientist who originally proposed the F40%msp reference point, William G. Clark: “It was motivated by the need of the North Pacific Fishery Management Council for a harvest rate to use in setting levels of acceptable biological catch or Alaska groundfish” (“F35% Revisited Ten Years Later”, 2002). Its development gave little consideration to similar groundfish populations on the East coast.
Since the implementation of the reference point on the West Coast, The Pacific Fishery Management Coincil has adopted different values for several species as an FMSY proxy, based on the advice of their peer review process. Nonetheless, the original F40%msp remains in effect for New England groundfish stocks.
In his op-ed, Dr. Rothschild noted that the “council does not have to go with the 40 percent reference point. It is scientifically acceptable for it to have gone with a 35 percent reference point. This is the level used to manage most species on the U.S. West Coast.” And he raised the question: “If 35 percent is OK on the West Coast, why is it not OK on the East Coast?”
As a result of the reasons and history outlined above, the NSC has asked the Council to consider returning to the direct calculation of Fmsy for stocks when possible, and to re-evaluate proxy values for Fmsy on a species-by-species basis. They also asked that an evaluation of the consequences of those choices, comparisons to other available data, and the effect on the rebuilding target for each stock also be evaluated.