Sunday, June 8, 2014

OF POLLOCK, MEMORY, AND THE NATURE OF "RECOVERY"

Thirty-something years ago, I wouldn’t have just written this blog.

In part, that’s because personal computers were still scarce and small, “Internet” was not yet a household word and the concept of “blog” still lay in the future.

But it was also because I would have been fishing for pollock somewhere out near Block Island.

I was living in western Connecticut then, so getting out to Block Island meant leaving the dock around midnight on Friday, and running through the night and the fog for most of the length of Long Island Sound.

If you’ve never been there, it’s tough to understand what it’s like to run a boat wrapped in a gray, wet blanket of fog that blanks out the stars and the shore lights alike, and makes the night itself feel damp and soft, like some sort of waterlogged velvet.

There’s that indescribable thrill of horror when the radar lights up with a couple score of bright dots, reminding you of the sailboat race headed down toward Stratford Shoals.  Now you’ve got to run the maze—well, not exactly blind, but without your own senses, depending on the glowing cathode-ray screen to get you through.

Eventually, you slide through The Race, cross Block Island Sound and finally enter the broad North Atlantic to begin the hunt.

At first, the depthfinder—it burns a black carbon image on a white paper roll—shows nothing worthwhile.  But then the bottom starts to look jumbled, with clouds—likely sand eels—above, so four-ounce jigs drop down to the bottom and the fishing begins.

Your world shrinks to a small patch of water, the handle of the reel in one hand and the grip of the rod in the other as you try to scrape a fish from the bottom below.  

You can feel the line on the reel’s spool carving grooves in the pad of your thumb.

And then the world intrudes again, as a black and silver shape, weighing maybe 25 pounds, crashes, still flapping, onto the deck by your feet.

You congratulate your friend for drawing first blood, then get back to work.

For a few minutes, his fish lies alone on the ice, but other pollock, and some small cod as well, soon join it.  As the fog begins to lift, more and more boats materialize out of the murk, and by the time that it burns off completely, you’re surrounded by a fleet representing multiple ports in New York, Connecticut and Rhode Island.

Every boat is catching pollock.

You don’t need too many, so you and your friends use single-hooked jigs, and catch fish one at a time.  But the charter fleet, trying to put its customers “on the meat,” catches them wholesale, trolling “umbrella rigs” with multiple hooks from weighted downriggers that let them keep their lures right in the pollock’s feeding zone. 

The goal is to hook two or three fish at a time, although the pollock—bigger than bluefish, and stronger than stripers—often tear the umbrellas apart before they can be dragged to the boat.

It was a wonderful, productive fishery that took place at the tail end of May and the beginning of June.  It gave anglers a chance to catch strong, good-eating fish at a time of year when there wasn’t too much else around, and provided the for-hire fleet something to fish for.

But you don’t hear about Block Island pollock any more, and you’ll have to talk to a lot of folks on the docks before you find one who can remember what they were like. 

Even the National Marine Fisheries Service’s official records don’t show much sign of it, because it died in the early 1980s, when New England trawlers were driving most of their groundfish into collapse, and the current methods of surveying anglers were in their earliest infancy.  

NMFS’ Marine Recreational Fisheries Statistical Survey—the forerunner to the Marine Recreational Information Program currently being adopted—was first rolled out in 1981.  It shows that about 750,000 pollock were landed in May and June of that year.

It also shows that number falling away quickly afterward, to roughly 180,000 in 1982, 125,000 in 1983 and 45,000 in 1984.  Pollock landings stayed in the 50,000-100,000 range for most of the next 30 years, with occasional variations both higher and lower.

The healthy spring pollock fishery is represented by just a single entry, for one single year, and is otherwise lost to both official and most unofficial memories.

Spring pollock are gone from Block Island.  Elsewhere, there have been a few more fish, and NMFS’ May/June recreational numbers have risen a bit—about 135,000 in 2010, 215,000 in 2011 and 265,000 in 2013 (but just 35,000 in 2012)—at best, about one-third of what anglers landed before the Block Island fishery died.

NMFS conducted a benchmark pollock stock assessment back in 2010, and tell us that the stock is fully recovered. 

Maybe it is.

However, the stock assessment also tells us, in its “Biology” section, that

“Pollock are abundant on the western Scotian Shelf and in the Gulf of Maine.  A major spawning area exists in the western Gulf of Maine and on George’s Bank, and several areas have been identified on the Scotian Shelf…Pollock grow to a maximum length of 110 cm and maximum weight of 16 kg [or about 35 pounds].”
There’s no mention of pollock living south of Cape Cod at all, of the historic Block Island run or of the fact that International Game Fish Association records show that Bruce Morabito caught a 45-pound pollock—nearly 30% heavier than the “maximum weight” given in the 2010 stock assessment—about 55 miles south of Long Island, New York back in the ‘80s.

Which could tend to make you wonder whether the folks who performed the stock assessment really understand what “recovery” means, or what a “fully-recovered” pollock stock would actually look like.

On its face, this would appear to be a classic example of the “shifting baseline syndrome,” a term coined twenty years ago by biologist Daniel Pauly, who noted that

“Essentially, this syndrome has arisen because each generation of fisheries scientists accepts as a baseline the stock’s size and species composition that occurred at the beginning of their careers, and uses this to evaluate changes.  When the next generation starts its career, the stocks have further declined, but it is the stocks at the time that serve as the new baseline.  The result obviously is a gradual shift of the baseline, a gradual accommodation of the creeping disappearance of resource species, and inappropriate reference points for evaluating economic losses resulting from overfishing, or for identifying targets for rehabilitation measures.”
Falling victim to the shifting baseline syndrome is unfortunate, but perhaps an understandably human and thus easily forgivable failing.  However, other, far less benign forces could have impacted the assessment.


The question is whether the new, higher quota was really justified by the science, or whether the fishermen “pushed” the assessment system in order to achieve a desired result.

For science is an inclusive process; the goal of any scientific process should be to determine the truth, and not to further personal agendas.  However, such an inclusionary principal also makes the stock assessment process vulnerable to manipulation, as it allows various interest groups—such as the various “sectors” of commercial fishermen up in New England—to pay “hired guns” to participate in the modeling meetings and try to “push” the decisionmaking process toward the conclusion that such groups prefer.

That may well have happened with pollock, as the stock assessment notes that both Dr. Doug Butterworth and his colleague Dr. Rebecca Rademeyer, both of the University of Cape Town in South Africa, participated in the meetings that came up with the population model.

Their presence is significant because of a bit of fisheries management arcana known as the “selectivity curve,” and its impact on stock assessments.  To make the discussion as painless as possible, stock assessments are dependent, in large part, on some sort of sampling of the fish in the water, in order to figure out how many there are.  Sampling can be “fishery independent”, and carried out by scientific surveys performed by biologists, or “fishery dependent,” which means what it sounds like—samples of catch.  In an ideal world, both types of samples are represented.

However, in order to be useful in a stock assessment, samples must actually reflect what’s going on under the water, and that’s where selectivity comes in.  For there are two types of ‘selectivity curves,” “flat-topped,” which samples all age and size classes, and “dome-shaped” which samples some of the age and size classes, while failing to detect others.

If you’re a fisherman who wants to kill more fish, you argue for a “dome-shaped” selectivity curve, because such a curve assumes the presence of fish that no one is catching or seeing, but that the domed curve says are out there. 

It just so happens that Drs. Butterworth and Rademeyer often find that “dome-shaped” selectivity curves are appropriate.  They have found that domed selectivity is appropriate in the case of both Gulf of Maine cod and South Atlantic wreckfish, while Dr. Butterworth, in collaboration with others, supported the use of “dome-shaped” selectivity for southern (Pacific) bluefin tuna and Atlantic menhaden.  He has noted that, with respect to New England groundfish, including pollock,

Which is what New England groundfishermen want to hear, because if Butterworth can convince fisheries managers to adopt dome-shaped, the trawlers get to kill more fish.

And that is apparently what happened with pollock.  The stock assessment notes

“…the ASAP model with dome-shaped survey and fishery selectivity implies the existence of a large biomass (35 - 70% of total) of pollock (i.e. cryptic biomass) that neither current surveys nor the fishery can confirm.  Assuming full survey selectivity for ages 6 and above reduces stock biomass and associated biomass reference points  by 20 – 50%. [emphasis added]”
In other words, the New England fishermen have convinced fishery managers to declare the pollock stock recovered, and increased harvest by 600%, on the basis of “cryptic” fish that may or may not exist, and that no one has actually ever seen

That’s a pretty remarkable achievement.

You can’t even find that kind of sleight of hand in Las Vegas.

As for myself, I think that I’ll cling to a different standard.


I’ll declare pollock restored when the fish return to Block Island.

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