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Guest Column: Move cautiously with Western Atlanic bluefin tuna 

by Rich Ruais

After the last complete Western Atlantic Bluefin stock assessment in 2014, Dr. Clay Porch (the lead bluefin assessment scientist for National Marine Fisheries Service) described the assessment results as follows:

“This is the most optimistic assessment we’ve had in years, although it’s important to recognize the uncertainties associated with it.”

Consistent with Dr. Porch’s perspective, Dr. Andre Boustany (Duke University/Stanford University/Monterey Bay Aquarium) was widely quoted as noting to the effect that “we have learned more about North Atlantic bluefin in the past 10 years than the previous 100 years.”

There is not any significant disagreement with either statement, which is evidence the Atlantic bluefin biomass is responding to the recent (post-1998) restrictive ICCAT quotas, size limits, improved accurate data submission, and a decline in illegal fishing or cheating anywhere along the way.

Or, the North Atlantic stock may be responding to a combination of lower western catches and favorable environmental changes for the fish.

If one looks at the world’s three distinct and separate bluefin tuna stocks – Pacific bluefin, Southern bluefin and the East and West Atlantic stocks – hands down, the North Atlantic stock is a huge success under the International Commission for the Conservation of Atlantic Tunas (ICCAT) traditional management strategies.

Consider that the western North Atlantic stock, with a 70% increase in spawning stock biomass (SSB) since 1998, is now at 55% of SSB as first measured in 1970.

The most recent assessment of Pacific bluefin estimates that SSB is at a dangerously low 2.5 – as compared with the earliest known measurement of SSB – and Southern bluefin is equally precarious at about 2.7.

The Western bluefin tuna has evolved from the decades-old poster child of so-called “bad fishery management” to the rising star and go-to fishery for anyone interested in eating bluefin tuna but highly concerned with bluefin conservation.

The progress in rebuilding stocks is not limited to tunas.

Recently, eminent world marine fish scientist Dr. Ray Hillborn has noted that “the perception that the world’s fish stocks are declining is incorrect.”  He further notes that “many stocks are increasing in many fisheries.”

Hillborn believes this conclusion is irrefutable.

Criticism of fishery managers, fishermen, and scientists involved with all three world tuna stocks is legitimate:

•  For allowing inadequate management and research programs to address scientific understanding, quota needs, IUU fishing, lack of adequate minimum sizes, inadequate closed areas to protect spawning fish where appropriate, bycatch, and many other common problems.

But now, the scientists and ENGO’s are ready to dazzle us all again with a transition to “autopilot” management tools of “new or modified reference points,” “harvest strategies,” “management strategy evaluation,” and more.

The new move is well underway.

The US regional councils and regional fishery management organizations are battling to secure the first new wave of “autopilot” management systems in place, particularly for the easier-to-manage,  single species fisheries.

Impact on West Atlantic bluefin

For the Western Atlantic Bluefin, the most recent stock assessment was held in 2014, with the next assessment scheduled for 2017.

The promised 2016 assessment was postponed because of lower-than-anticipated progress on transition to a bluefin assessment that incorporates the mixing of eastern and western bluefin on the fishing grounds and
along migratory routes.

Incorporating “mixing” of eastern and western origin fish on the feeding and fishing grounds of the Atlantic in stock assessments has been the Holy Grail of scientists ever since genetics data indicated that the North Atlantic stock was something other than a “single stock.”

As we approach the 2017 stock assessment we are again told the methodology is not yet ready for a stock assessment that incorporates the mixing of the two stocks.

We have also been told that development of the first-ever Management Strategy Evaluation (MSE) – a relatively new method for developing scientific advice – is also not ready to move forward.

Predicting the impact of a major transition in methodologies and process in rebuilding/stabilizing a stock is difficult.

Factors such as “data poor/data rich,”  whether the stock(s) are managed in one EEZ or many, and the complexity of mixed fisheries or single targeted species compounds the difficulty.

It is clear that the common thread between a transition to strict adherence to MSE, control rules, harvest strategies, reference points, and other “formulaic” support activities is the fact that:

•  These new processes – by intent and definition – will be implemented at the expense of managers, fishermen, and other stakeholders who will lose influence, and possibly more nuanced decision making control, over the bluefin fisheries.

Hence, the term “scientific autopilot” seems appropriate, at least until proven otherwise.

Identifying the major problem

Now fast forward to 2020 or later when the new mixed stock assessment and MSE process are ready for their first implementations with new objectives to guide the MSE scientists tool.

The new potentially common Atlantic wide resource (with separate stocks, metapopulations, large and small assemblages in “distant patchy realms”) gets inputted into the MSE model to issue the Harvest Control Rule (or country quotas).

What if the new quotas leave:

•  Algeria, a country accustomed to and dependent on catching over 2,000 mt of bluefin per year, receiving only 244 mt, i.e. 2014, level under MSE;

•  Tunisia, where historical catches are over a wide range, but 2,500-2,700 mt are common),  receiving only 1,047 mt;

•  Or EU Spain, in the East Atlantic and Mediterranean with about 6,000 mt at the 1998 level, only receiving 2,447 mt;

•  In the West Atlantic, Canada, with historical catches between 600-700 mt, receiving  463 mt; and

•  What if Japan, on the basis of an objective favoring best and longest CPUE data, hits the MSE “Wheel of Fortune” and gets 691 mt, (i.e. their annual quota when the rebuilding plan started in 1998)?.

There seems to be a serious lack of recognition at how dramatic changes to the international regime could be under a new mixed stock assessment and MSE advice that does not prioritize control rule considerations.

In other words, MSE is not going to stop the intense battles over quota share of a valuable pelagic species regardless of the fact the managers selected these new criteria.

The winners will be smiling, but many of the losers will be running to fill out formal objection forms.

To many of these countries, the prior, agreed-to MSE control rule objectives will become entirely irrelevant and managers will be helpless to restore historical performance as well as other objectives already underlying ICCAT’s Recommendation on Criteria for the Allocation of Fishing Possibilities.

Formal objections will abound, and where does ICCAT turn to then?

Reruns of MSE using multiple new criteria or formulaic recommendations?

New England council’s herring MSE exercise 

For Western Atlantic Bluefin, a combination of electronic and conventional tags, otolith microchemistry examination and genetics, and more have been used in attempts to unravel the mysteries of stock mixing between eastern and western origin bluefin.

A few bluefin scientists believe they have solved the mysteries, while most agree that a clearer understanding (i.e. more data) of mixing is required for an efficient and equitable long
term conservation plan.

But now, with the incredibly complex efforts to conserve, at least, two highly migratory stocks of bluefin (while unravelling dynamic migratory paths of large assemblages of East and West origin fish chasing food), some ENGO’s and contracting parties are insisting upon introducing new management and scientific tools likely to further delay the first “mixed” North Atlantic bluefin assessment.

These tools include the above discussion and implications of MSE, new biological reference points and triggers (beyond KOBE Plots) between East and West stocks, harvest strategies introducing a number of unfamiliar processes and finally a set of yet to be developed but certainly contentious, management objectives.

Further, the New England Fishery Management Council has set a mandate for Atlantic Herring Amendment 8 to incorporate MSE and has agreed to an objective of identifying the theoretical minimum amount of Atlantic herring necessary for bluefin and other species forage needs.

One small problem here is that they only have information on the forage needs of the Western bluefin biomass and therefore they intend to ignore the consumption of West Atlantic herring by Eastern bluefin migrants (with estimates of Eastern bluefin biomass being 10 times as large as the west), all foraging at the same time in the Gulf of Maine.

Given that some studies have placed the estimate of Eastern bluefin foraging on Gulf of Maine herring at levels as high as 80%-90%, basing Herring Area 1A TACs on this MSE analysis would endanger both the health of Atlantic herring but also be a strong incentive for bluefin to quickly look elsewhere for what should be a relatively easy daily meal of herring.

The error of leaving out the consumption by Eastern bluefin migrants would also damage the traditional Northeast bluefin fishery given the bluefin’s appetite and fearless approach for long migrations to find forage.

Now, if these are not enough reasons to urge managers on both sides of the Atlantic to proceed cautiously with significant changes to assessment and management of bluefin, consider this:

•  Here in the US, the NMFS Highly Migratory Species division has initiated the planned three-year review of every aspect of Amendment 7 – from seasonal quotas; potential dismantling or selling off the purse seine quota within the Individual Bluefin Quota program designed to help revitalize the US longline fleet while reducing discards; and making permanent new area bluefin fisheries with the accompanying economic dependency and other potentially major and minor rulemaking changes.

Would it not be wise to delay the Amendment 7 review until such time as the potential changes to the current international program under a mixed stock/MSE based regime are known?

Imagine the volume of wasted constituent time and NMFS staff time to develop a new amendment only to find it is inconsistent with many of the major provisions of the new ICCAT plan.

Why not limit or target relatively easy and obvious currently ineffective measures, while NMFS’ HMS staff and constituents pursue with full attention a reasonable mixed stock/MSE based regime, if one can be devised?

Good luck this season and beyond.

Rich Ruais is executive director of the American Bluefin Tuna Association.

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