Sunday, November 26, 2017

BAD NEWS FOR ATLANTIC BLUEFIN

Bluefin tuna and I go back a long way.

I saw my first bluefin in the summer of 1960.  I had just turned six years old, and my family was on its annual vacation, that year to Provincetown, at the end of Cape Cod.  We were walking along the fish pier, looking at the party boats that we might be fishing from the next day, when we came across the Inca.

Unlike the chunky, workmanlike party boats that took dozens people each day out to the ledges where cod, pollock and similar bottom fish swam, the Inca was a thoroughbred, a sleek, black charter vessels that carried a handful of anglers out to blue water, where they pitted their heart and their muscles and lungs against the great gamefish of the open sea.

And that day, the anglers were successful, for the Inca’s cockpit was filled with two giant bluefin, fish so large that their bodies dwarfed those of the anglers who caught them.

The next day I went out on my first codfishing trip, when I could barely hold up my rod and keep reeling against the pull of a pretty small cod.  Even so, thoughts of those giant bluefin hung heavy on my mind.

It wasn't until fifteen years or so later that I first crossed paths with a living bluefin.

There was a chop on the ocean south of Rhode Island, as whitecapped green waves churned underneath an overcast sky.  But the whitecaps couldn’t hide the explosions of spray pushed up by a school of feeding giants.

We weren’t equipped for such fish.  Sharks were our target that day, not warm-blooded fish that weighed a quarter-ton or more and were strong as bulls.  Even so, lines were set into outrigger clips, and our boat turned to cut off the foraging school, the biggest lures on board trailing in its wake.

I happened to be standing next to the rod that the bluefin chose.  I stood still, startled, as its tip arched toward the water and 80-pound mono began to peel off its spool.  I had just snapped out of my momentary paralysis, and was trying to get the rod out of its holder, when the tip snapped back up and the fish was gone.

It was probably just as well, because without a fighting chair and kidney harness, had the hook held, the fight probably would have ended badly.

The next time, I was better prepared, with a 130-pound rod, harness and chair.  Even so, I was a bit intimidated when the boat’s captain tested the fit of my harness by grabbing the rod with both hands and lifting his feet off the deck so that I was supporting all of his weight with my back and legs.

But by then, the bluefin’s post-1974 decline had begun, and 
no tuna tested me further.

Later, fishing first from charter boats and later from my own vessels, I caught my share of bluefin, and put anglers on others, although none of those fish were as large as those that first inspired my quest.  I watched the population shrink, until I couldn’t, in good conscience, try to catch any more.
In recent years, it seemed that the stock was rebuilding, enough so that I returned to the fishery, targeting bluefin last summer for the first time in a decade.

But this month, the International Commission for the Conservation of Atlantic Tunas decided, based on very uncertain evidence, to halt its successful rebuilding effort and increase bluefin tuna mortality on both sides of the Atlantic.
Such action was not taken arbitrarily, but was instead based on advice contained in the October 2017 report of ICCAT’s Standing Committee on Research and Statistics, which did a masterful job of pairing substantial uncertainty with a lack of information, and weaving them together into a recommendation to halt the recovery effort and increase the bluefin tuna kill, in both the eastern and western Atlantic.

The October SCRS report to ICCAT states that

“Recent assessments of both the eastern and western stocks have attempted to develop Kobe plots and matrices [hyperlink added] depicting the status of the stock relative to certain reference points, despite a consensus that they did not adequately reflect the true range of uncertaintiesThe long-term recruitment in particular is unknown and probably changes over time…
“…In the absence of such knowledge…[t]he reference point of choice for the Eastern stock has been F0.1 [hyperlink added] since 2008. The 2017 Committee considers F0.1 to be a reasonable proxy for the western stock as well...Yields associated with F0.1 can be higher or lower than [maximum sustainable yield]-based yields, depending on the spawner-recruit relationship…  [emphasis added]” 
pparentlys, because of uncertainties about future recruitment and the spawner-recruit relationship, ICCAT’s SCRS was willing to adopt a management approach that could lead to a harvest greater than maximum sustainable yield, rather than opting for a more precautionary approach that would better ensure the sustainability of the bluefin stocks.

The impact of ICCAT’s actions was greatest in the eastern Atlantic and Mediterranean, which will still impact bluefin tuna fishermen on this side of the Atlantic, because the eastern and western Atlantic bluefin stocks cross the ocean basin, and quite a few of the tuna that we catch over here are spawned somewhere east of the Pillars of Hercules.

ICCAT decided to sharply increase eastern stock bluefin quotas by phasing in 4,000 metric ton annual increases over the next four years, which will raise the overall quota from 24,000 metric tons in 2017 to 36,000 metric tons in 2020.  

Such increase was adopted despite the fact that

“there was still concern over the performance of the [virtual population analysis model used to assess the stock], notably the unstable estimation of total biomass (i.e. the estimating of a substantial overall increase in biomass with the addition of only the last year of data) and that the size composition of many eastern Atlantic and Mediterranean fleets is poorly characterized for a number of years before…2014.”
However, the increase was in line with explicit, although somewhat schizophrenic, SCRS advice.  The SCRS said that

“catches up to 38,000 t or 36,000 t have a greater than 60% probability of maintaining [fishing mortality] below F0.1 in 2020 or 2022 respectively.”
Thus, the ICCAT action would have a somewhat better-than-even chance of preventing overfishing, as ICCAT chose to define it, although it would not necessarily keep harvest at or below maximum sustainable yield.  However, the SCRS also advised that

catches of 28,000 t or less have a higher than 50% probability of allowing a continue [sic] increase in the stock.  [emphasis added]”
To the extent that F0.1 results in a harvest that exceeds the maximum sustainable yield, the stock could even start shrinking again.  However, the SCRS didn’t seem to be particularly concerned about a shrinking stock, as it recommended that

“Given the abundance increase evident for the stock, the Committee advises that the Commission should consider moving from the current rebuilding plan to a management plan.”
ICCAT didn’t explicitly take such action, but given the SCRS’ predictions, it appears that the prospects for future rebuilding are pretty much nil.

Predictably, the conservation community wasn’t pleased with ICCAT’s actions.  The Pew Charitable Trusts noted that the new quota is

“the highest ever for the population and one that risks returning catch to the levels seen when the stock was in crisis a decade ago.”


“WWF is angered that ICCAT has chosen short-term economic profit when we had hoped for a long-term conservation victory.”


“there was still room for a higher [harvest].  Our fishermen have faced hefty cuts over the past years in their quotas which led to a successful recovery of the stock; yet again their efforts are not duly rewarded by the international community.,”
That only proves that not only can fisheries managers fail to please everyone, for despite their best efforts, they can often fail to please anyone.  Thus, it probably makes more sense for managers to concentrate on conserving and rebuilding fish stocks, and not worry about who they offend.

In the case of western stock bluefin, the harvest increase will be much smaller—about 17%, compared to more than 50% for the eastern stock—but the decision to bump up the kill is in some ways more disturbing, because it comes at the end of a 20-year rebuilding plan that, according to a National Marine Fisheries Service scientist who headed up the bluefin stock assessment panel a few years ago, was working pretty well, although it was still far from achieving its goals.

That scientist stated, in 2014, that

“The stock has recovered to about one-half the level it was when we started tracking the data in the 1970s.”
That is more or less in accord with information provided in the October 2017 ICCAT SRCS report, which said that one of its stock assessment models placed western stock abundance in 2015 at about 69% of where it was in 1974, while another placed it at just 45% of the 1974 biomass.

Unfortunately, the October SCRS report also notes that

“the 2003 year class is past its peak biomass, recruitment has been declining for a number of years and there are no signs of a strong year class coming into the fishery.”

Under such circumstances, it wouldn’t have been unreasonable for ICCAT to initiate a new rebuilding plan which would call for decreased landings in order to continue the recovery of the stock.  However, just the opposite 
occurred.

As was the case with eastern stock bluefin, the SCRS recommended abandoning biomass targets, and thus the concept of recovery, completely, in favor of a F0.1 fishing mortality target—the same fishing mortality target that the SCRS acknowledged could result in landings that exceed maximum sustainable yield under some recruitment scenarios.

And the SCRS notes that western stock recruitment is declining, with no strong year class in sight…

That being the case, it doesn’t appear that the bluefin tuna’s prospects, in either the eastern or western Atlantic, will get better at any time soon.

Instead, any hopes of an increase in abundance seem to have been dashed, and the chances for harvest exceeding maximum sustainable yield appear pretty high.

Despite that, there are some folks here in the United States that will probably hail ICCAT’s decision. 


I suspect that both commercial and recreational fishermen on Cape Cod and in northern New England will praise it as well, claiming that they see plenty of western stock bluefin.  But the folks up there, near the heart of the bluefin’s summer range, always saw quite a few bluefin, just as they still do today.  It is the other historical fisheries that are hurting.


“In Rhode Island, Rosie’s Ledge and Nebraska Shoals are best known for the giants but they can be found in other spots along that rocky shore.  Montauk, N.Y. boats often head toward Block Island and the coast of Rhode Island to fish for giants.  New York City and New Jersey anglers fish the Mudhole, 17 Fathoms and adjacent areas for the big tuna.”
All of those places are close enough to shore that an angler could just about see high points of land on a clear day; it’s safe to say that few giant bluefin have been caught in such places in the last twenty years (although there are a few big fish that pass close by New York and New Jersey during December). 

ICCAT’s SCRS is having trouble defining what a fully recovered biomass would look like.  While it may be impossible to describe that recovery in terms of metric tons of tuna, it’s easy to describe the results:  When  anglers can readily catch giants again at places like Rosie’s Ledge off Rhode Island and the Butterfish Hole of Block Island/Montauk around Labor Day, and along the edge of New Jersey’s Mud Hole in November, the stock might be close to recovered.


Until then, managers have work to do, and ICCAT’s time would be far better off trying to increase the number of bluefin alive in the water, rather than working so hard to increase the number of bluefin dead on the dock.

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