The following article was published by the Coastal Conservation Association:
July 2, 2012 – Last week the Atlantic States Marines [sic] Fisheries Commission’s (ASMFC) Stock Assessment Committee and Technical Committee met to finalize the stock assessment update and advice they may give the Board for managing menhaden.
To reset the situation, according to the last benchmark assessment four years ago, the stock was undergoing overfishing, recruitment was at or near an all-time low, and abundance was at an all-time low. Not a good situation for a species whose primary ecological attribute is its historic, teeming abundance which has made it one of the primary forage species for gamefish like striped bass, bluefish, weakfish, bluefin, king mackerel and many others.
Menhaden has been allowed to decline to this low level using the reference points endorsed by the Technical Committee and the management advice based on those reference points by the Technical Committee. Simply put, the advice of the Stock Assessment Committee and the Technical Committee has failed the Board and the fishery.
At the last benchmark assessment, independent scientists reviewed the stock assessment and noted what the public has been saying for years: the stock is in a state of decline. Yet the management guideposts (reference points) did not signal any problems. The independent scientists suggested the Management Board adopt new reference points that took into account the historic abundance of menhaden.
So it was not surprising that the Board took the advice of the last peer review and adopted new, more conservative reference points. They adopted a 15 percent Maximum Spawning Potential (MSP) – which is a spawning stock that is 15 percent of an unfished stock – as the threshold and 30 percent MSP as the target, all perfectly reasonable, commonly used reference points. At the time it would have taken an estimated 10-15 percent reduction in harvest to meet the threshold of 15 percent MSP, and about twice that to meet the target reference point mortality rate.
The Board asked for a stock assessment update (which would add three more years of data to the last benchmark assessment to see where we are today), and that’s where the current problems start. The model started acting up when the last three years of data were added. The Stock Assessment Committee finally came to the conclusion that the results were so questionable that it was not useable for offering management advice. The two Stock Assessment Committee members who argued the hardest for not offering any management advice until the stock assessment was fixed were both employees of the National Marine Fisheries Service (NMFS).
Not to be forgotten in this new intrigue are the facts that this is a stock for which managers have a 55-plus-year time series of data, it is at a low level of abundance, there is evident age truncation, and the fishing mortality rate has been increasing in recent years.
And the Technical Committee can’t offer management advice? Really?
Read the full story from the Coastal Conservation Association.
Analysis: The Coastal Conservation Association, in its article "Menhaden Management Not Passing the Smell Test," alleges that the Stock Assessment Subcommittee and Technical Committee of the Atlantic States Marine Fisheries Commission (ASMFC) are being unnecessarily cautious in the preparation of advice they are developing to eventually be delivered to the full Commission for menhaden management. It criticizes the menhaden Stock Assessment Subcommittee for concluding that they do not have enough information to offer appropriate management advice, based on the unreliability of the current data. The author, Ted Venker, argues that the previous 55 year series of data is sufficient to manage the stock. In doing so, the author understates problems with the current management model, and the uncertainty surrounding the most recent data collected on the fishery.
At the last menhaden Technical Committee meeting, it was observed that the updated assessment showed a retrospective pattern, meaning that the estimates in previous population assessments contradicted the population estimates in the current assessment, and needed to be revised in order to fit the more current data. The appearance of retrospective patterns is a sign that a particular stock assessment model may not be working and that the data being produced is not reliable. To fix a retrospective pattern the assumptions that went into making the model need to be revised. Chris Legault, Chair of the NOAA Retrospective Working Group in their January 2008 Report wrote, "a strong retrospective pattern is grounds to reject an assessment model as an indication of stock status or the basis for management advice."
The appearance of a retrospective pattern is not the only problem with the menhaden update assessment, as the fish abundance indices have also produced contradictory and unreliable data. The menhaden assessment uses two separate indices that are compiled to estimate the total population size: an index of older fish based on fisheries data, and an index estimate of juvenile fish obtained from shallow water sampling. The juvenile abundance index has remained stable over the last few years, while the adult abundance index has been increasing. If the proportion of older fish in the population is increasing, but juveniles are remaining constant, this implies that fewer adult fish are being removed from the water. The assessment asserts the opposite.
According to the assessment, fishing mortality is actually increasing. To explain this inconsistency in the assessment, it is possible that either the calculations for the model used on the indices are inaccurate and producing faulty data, or that the claim that mortality is increasing is incorrect. Having an inaccurate measure of both abundance and mortality makes it difficult to determine if fishing targets are being met, and makes it hard to recommend appropriate catch limits. This problem was recognized by the ASMFC in its reluctance to use this data to formulate management advice.
The appearance of many such issues has raised concerns within the menhaden Stock Assessment Subcommittee. Matt Cieri, a Subcommittee member, stated in their June 15th conference call, "The problem is that we've uncovered major problems with the tool we were planning on using to determine status and do projections." Erik Williams, Chair of the menhaden Technical Committee, also expressed doubt about the usefulness of the data in a May 29th conference call. "We also need to decide whether this is useful for management right now," he said. "Unfortunately, we don't have the time to fully understand what is going on, but we can convey the troubling diagnostics we're looking at." These views were part of the consensus reached by the Subcommittee that the current data might not be reliable enough to serve as the basis for important management decisions.
The article also makes the accusation that May's menhaden Technical Committee meeting included inappropriate participation from industry experts, Drs. Doug Butterworth and Michael Prager, claiming that they, "nearly led the discussion." However, Bob Beal, acting Executive Director of the ASMFC, stated in an interview that their participation did not violate protocol, saying, "My understanding is that they weren't inserting themselves beyond what the chair was allowing at the meeting."
By criticizing the ASMFC for its hesitance to make management decisions based on flawed data and its acceptance of outside advice, Mr. Venker a ignores the goal of the stock assessment process, which is to manage the stock according to the most up-to-date and scientifically sound data. The author advocates managing the species based on unreliable data, which would benefit neither the interests of the fishery, nor the long-term goals of conservationists.