Sunday, February 26, 2017
Fish have traditionally been managed on a single-species basis. That is, biologists calculate a target level of abundance for each species, along with a lower threshold biomass that is used to determine whether a stock is or is not overfished.
To maintain a stock at its target level, or to rebuild it if abundance has fallen too far, biologists also calculate a target fishing mortality rate, and a threshold rate that, if exceeded, warns that overfishing is taking place.
Such calculations are made without reference to any other species that shares the managed stock’s environment, except to the extent that a lack of forage fish, or an abundance of predators and competing species, might impact that part of the overall mortality rate not attributable to fishing.
On the whole, single-species management has worked pretty well, although it may not be adequate to calculate the number of forage fish, such as Atlantic menhaden, that should be left in the sea to provide food for predatory fish, birds and marine mammals. Even so, a number of biologists have suggested that it is time to move on from single-species management to a more holistic approach generally referred to as “ecosystem management” although, given how many different factors impact any given ecosystem, that title suggests a more comprehensive management program will probably ever be practical.
“The current U.S. fisheries management system regulates fishing on individual populations or groups of similar populations. Although improvements to the law have helped to end overfishing on many species and to rebuild a number of depleted populations, they do not address the bigger picture. Each fish is a link in overlapping food chains that form an interconnected food web of places, plants, and animals. Ignoring these connections can lead to serious consequences and cause dramatic shifts in the health of the ocean.”
Recently, a number of similar arguments have been made by various marine conservation advocacy groups.
Yet, even though ecosystem management has been getting a lot more attention in recent years, the concept is nothing new. The Sustainable Fisheries Act of 1996 mandated the creation of an Ecosystem Principles Advisory Panel, which completed its report to Congress, entitled “Ecosystem-based Fishery Management,” late in 1998. That report noted that
“Seeking solutions to reverse the decline of New England’s fisheries in 1871, Congress created the U.S. Commission of Fish and Fisheries. The first appointed Commissioner, Spencer Baird, initiated marine ecological studies as one of his first priorities. According to Baird, our understanding of fish ‘…would not be complete without a thorough knowledge of their associates in the sea, especially of such as prey upon them or constitute their food…’ [emphasis added]”
Thus, it’s clear that neither the concept of ecosystem management nor the reality of troubled New England fisheries are recent developments.
However, there is a big difference between talking about ecosystem management and putting ecosystem-based programs into practice. When I sat on the Mid-Atlantic Fishery Management Council from 2002-2005, I was asked to become the first Chair of the Council’s newly-created Ecosystem Management Committee (since renamed the Ecosystem and Ocean Planning Committee). A dozen years would pass before the Council would approve its “Ecosystem Approach to Fisheries Management Guidance Document,” which was just posted to the Council website earlier this month.
So progress in this area doesn’t exactly progress with lightning speed.
One of the reasons for that is that people just don’t agree on precisely what “ecosystem management” means. The Mid-Atlantic Council’s Guidance Document states that
“An ecosystem approach to fisheries management recognizes the biological, economic, social, and physical interactions among the components of ecosystems and attempts to manage fisheries to achieve optimum yield taking those interactions into account.”
That’s a very broad definition, certainly larger than the Pew position paper’s concentration on “overlapping food chains that create an interconnected food web of places, plants, and animals,” or Fish and Fisheries Commissioner Baird’s concerns with managed species’ prey and predators. Once economic and social factors are considered, they can become wild cards that upset any emphasis on biological relationships.
The Guidance Document eases those concerns by stating that it is focusing on four issues primarily linked to biological/oceanographic considerations, including
“1. Forage/low trophic level species considerations;
2. Incorporation of ecosystem level habitat conservation and management objectives in the current management process;
3. Effects of systematic changes in oceanographic conditions on abundance and distribution of fish stocks and ramifications for existing management approaches/programs; and
4. Interactions (species, fleet, habitat, and climate) and their effects on sustainable harvest policy and achievement of [optimum yield],”
with a footnote indicating that
“Social and economic considerations were integrated throughout the analysis of the four topic areas.”
That’s important, because there is a very thin line between “ecosystem management,” that takes a holistic approach to management by striving to maintain sustainably-harvested fish stocks within an intact ecosystem, and by adopting management measures to changing ecosystem conditions, and “ecosystem engineering” which makes an effort to maximize social and economic benefits by reducing the abundance of organisms deemed “less desirable” or “less valuable” while artificially increasing the abundance of those that, for one reason or another, are more valued, and change the natural structure of the ecosystem along the way.
Fishermen tend to confuse the two concepts. When I sat on the Mid-Atlantic Council, I remember hearing comments from both Council members and the public to the effect that the Council shouldn’t try to manage spiny dogfish, because they only take up space and resources in the ocean that could better be utilized by more valuable species.
And whatever the species being managed, there is always someone willing to argue either 1) fishermen aren’t the cause of a species’ decline; the real problem is that they’re being eaten by something else (which should thus be killed off in greater numbers), or 2) restrictions on the harvest of a particular species should be relaxed, because “they’re eating everything in the ocean.”
Comments of the latter sort can devolve to the level reached by one of New York’s representatives to the Atlantic States Marine Fisheries Commission’s Summer Flounder, Scup and Black Sea Bass Advisory Panel, who said—with a straight face—that
“All those scup are eating lobster roe, small crabs, shellfish, and baby flounder…When one species grows so much, it’s going to wipe out some other species…Sea bass and scup are growing enormously and need to be contained to a reasonable amount. You can’t allow one species to devour everything else…
“The biomass for sea bass is so much higher than what we have recorded. They’re wiping out other species. If we don’t act soon you’re going to lose the lobster fishery throughout the northeast. We need an emergency opening of both the commercial and recreational black sea bass fishery…”
Of course, scup and black sea bass have been living alongside lobster, crabs, shellfish, flounder and many other creatures for tens of thousands, if not millions, of years without fishermen to keep them from “devour[ing] everything else," and the local ecosystem seems to have gotten along pretty well.
If anything, it was an overpopulation of fishermen, not fish, that put various species at risk.
Off the coast of China, a strange and very dark sort of ecosystem management, that may be replacing the natural order that evolved over the ages, is playing out right now.
According to a recent article in Hakai Magazine, despite at least twenty years of essentially unregulated industrial fishing, China has been able to maintain consistently high levels of harvest.
That seemed so unlikely that the folks who make their living studying fisheries and their impacts on fish stocks thought that the Chinese government was inflating the landings numbers. Now, according to Hakai, researchers in British Columbia are looking at the Chinese numbers in a different light. They believe that the harvest numbers are more-or-less accurate, and think that they can be sustained because the Chinese have effectively, if unintentionally, created a sort of engineered ecosystem in which fishermen eliminated most of the large oceanic predators in the region.
The article explains that
“Killing predators allows prey numbers to boom and, much like how deer populations have exploded in the United States since humans extirpated wolves from much of their range, this approach has allowed fish species lower on the food chain to retain high numbers. And because predators typically need to eat 10 kilograms of prey to add one kilogram to their own weight, fishing out predators tends to increase prey catches by much more than it reduces predator catches, the study authors say.
“…China’s approach—which is similar to that of other Asian countries such as Indonesia, Thailand, and the Philippines—has downsides, such as degrading ecosystems and lowering biodiversity…
“But if [Chinese fisheries managers] follow the US practice and implement single-species management, their catches will decrease…That’s because single-species management in effect creates extra competition for fishers…Allowing some fish to grow larger means more big fish eating more of the fish that humans also target.”
The sort of “ecosystem management”—or, perhaps, “ecosystem non-management”—is the conservationists’ nightmare, and it effectively reduces the ocean into a sort of food-fish factory in which the naturally-established food web has been almost completely disrupted. It is a far cry from the sort of ecosystem management envisioned by Pew and other conservation advocates, the late Commissioner Baird or the Mid-Atlantic Council’s Guidance Document. And as consistent as yields have supposedly been, some scientists warn that a crash will inevitably come.
However, it is easy to see how such “management” might be attractive to a government that seems to care nothing for natural processes or wild places, and is obsessed with the rubric of “creating jobs” and “economic gain.”
Thus, as we move down the road toward ecosystem management, it is essential that we keep our eyes on the ultimate goal of healthy, intact ecosystems that can provide fisheries that are sustainable in the long term.
We must not allow ourselves to be seduced by the promise of engineered ecosystems that strip natural systems of their essential integrity and replace it with a structure that may or may not be sustainable, but is designed solely to reflect current social and economic values.
Thursday, February 23, 2017
A lot of anglers won’t even consider eating a sea robin.
The reddish-brown fish with gold-rimmed blue eyes and broad pectoral fins, which “flies” over bay bottoms in its quest for food, has been historically shunned and reviled by most anglers who catch them while seeking summer flounder and other, more traditionally attractive species.
Yet there are increasing numbers of anglers who know better, and look forward to taking sea robins home for dinner.
My wife and I began eating sea robin years ago, when fluke were scarce and there was little else to eat in the bay. Porgies were small and hardly worth cleaning, when you could find them at all, and the tiny “pin” black sea bass that we caught in those days, before bag and size limits were imposed, provided smaller fillets than a duck-pond bluegill. We filleted a few sea robins, and found that they were good.
As the years passed, more anglers jumped onto the sea robin bandwagon. National Marine Fisheries Service recreational catch estimates show that, for the period 2007-2011, anglers in the New England and Mid-Atlantic regions harvested an average of 61,700 striped sea robins each year; for the period 2012-2016, that average more than doubled to nearly 155,000 sea robins landed.
There is clearly an upward trend.
It was only a matter of time before sea robins began to be harvested commercially, and made the leap into the marketplace. That seems to be happening now, as reported commercial landings also show an increase over the past decade. For the period 2007-2011, commercial fishermen on the Atlantic coast landed an average of 93,200 pounds of sea robins each year; that figure increased to an average of 140,400 pounds for the period 2012-2015.
Further evidence that sea robins may be entering the mealtime mainstream recently emerged on the Internet, where the website Eater.com posted a video of a New York seafood shop owner demonstrating how to clean and cook them.
In some ways that’s good, because diversifying the kinds of fish that we eat will take some of the pressure off the most heavily harvested species.
But it’s also bad, because there is currently no management plan to protect sea robins. There are no closed seasons, no limits on harvest and, if we want to be honest, probably no data to suggest what such seasons and limits might be.
Should eating sea robin ever become a dining fad, it is not impossible that the fish that now seem to sometimes carpet the bay could become overfished in a very short time.
There is certainly precedent for such a thing happening.
For years, oyster toadfish were common in New York’s bays.
Looking like a sort of mutant tadpole, with slimy skin, a wide mouth filled with mollusk-crunching teeth and a willingness to eat anything that might fit in their mouths, they were one of the last things that anglers wanted to see at the end of their lines.
When they were caught—and they were caught frequently in the soft-bottomed back bays—fishermen tended to handle them with rags and/or pliers, and wanted nothing more than to drop them back over the side.
And then, more than two decades ago, something changed.
A new wave of immigrants entered the nation, who didn’t find toadfish repulsive at all. They were accustomed to eating somewhat similar creatures that lived in their former home waters, and to them, toadfish weren't just something ugly.
Instead, they were good food.
Suddenly, baymen who had been trying to eke through the summer catching killies and a few blowfish had a chance to create a completely new fishery, targeting a species that was abundant, valuable—big toadfish, sold live, were worth at least $2.50 per pound, which was good money back then—and not subject to any regulations at all.
The outcome was predictable.
Some folks made for two or three years, selling toadfish to urban live-fish markets as fast as they could be caught. Then things began to slow down, and get slower yet, until, at some point in the late 1990s, New York’s Department of Environmental Conservation finally regulated the fishery to keep the toadfish population from falling into a state of complete collapse.
Today, a bayman on Long Island may harvest no more than 25 toadfish per day, must observe a 10-inch size limit and can’t keep them at all between May 15 and July 15. Such regulations were better than nothing, but the damage was already done.
New York’s commercial fishermen reported landing 13,000 pounds of toadfish in 1992, 35,000 pounds in 1993 and an all-time high of more than 42,600 pounds in 1994. By 1996, that figure had fallen to just 2,000 pounds, then crashed even farther, to 169 pounds, the following year. Despite the current regulations, annual landings have not exceeded 1,000 pounds since, coming the closest in 2014, when 837 pounds of toadfish were reportedly sold.
It would probably be close to impossible to find a better example of a boom-and-bust fishery, in which unregulated fishermen harvested so many previously underutilized fish that they collapsed the population in a very short time.
The result of such overharvest was typical as well. Twenty years after New York’s toadfish population crashed, that population remains far too depleted to support a viable fishery.
Populations of some once-abundant food fish, such as New England cod and winter flounder, are badly depleted, and the populations of many others, while healthy, are under significant pressure. There is a temptation to seek out so-called “underutilized species”—what fishermen will sometimes thoughtlessly deem “trash fish”—and try to develop markets for them, in order to help fill the demand for local seafood.
While creating markets for erstwhile “trash” species sounds like a good idea, engaging in a fishery for any largely unregulated species is always a risky undertaking.
Government agencies rarely spend money to research species without any significant economic value. As a result, fishery managers have little idea what to do when a fishery for a previously underutilized species begins to take off.
For that reason alone, new fisheries should always be developed cautiously, with precautionary regulations put in place to help assure that the sad saga of New York’s toadfish is not reenacted at another time and place, with another species playing the toadfish’s role.
Today, when more desirable species aren’t available, anglers can still find so-called “trash fish” such as sea robins to provide some action and a few fillets.
But if markets for such species are developed, and regulations aren’t adopted at the same time, anglers may one day find themselves asking the question “What do we fish for now, when even the trash fish are gone?”
Sunday, February 19, 2017
Various angling industry, boatbuilding and “anglers rights” groups, upset that the current, science-based federal fisheries law doesn’t let anglers kill as many fish as some might like to, have been making the argument that federal fisheries managers shouldn’t tie their regulations so closely to science and data, but rather should employ less statistically-rigorous means to regulate recreational fisheries.
“fisheries that sufficiently meet the needs of recreational anglers while providing extensive economic benefits to their state and national economies.”
It’s immediately apparent that the health of fish stocks or the integrity of marine ecosystems are not addressed by that industry statement.
Instead, the tackle and boatbuilding industries effectively encourage fisheries managers to tolerate chronic growth overfishing, when so many small fish are harvested that few older and larger fish survive.
The Louisiana fishery for speckled trout (more properly known as “spotted seatrout”), in which managers tolerate growth overfishing so long as recruitment overfishing, when the number of new fish entering the fishery drops substantially, doesn’t occur, is an example of what such fisheries looks like. They have high bag limits, low minimum sizes and very long seasons—if they have any seasons at all.
By removing most restrictions on harvest and letting anglers keep a large proportion of everything they catch, such fisheries tend to maximize angler participation, at least until recruitment overfishing kicks in and the fish begin to disappear. And as any angler knows, the more someone participates in a fishery, the more money they spend, so it can be argued that growth overfishing will provide “extensive economic benefits to…state and local economies”—and to the same angling and boatbuilding industries who are advocating for such a management approach.
Biologists, on the other hand, have argued that managers should be concerned with, and intolerant of, growth overfishing, noting that
“Since old fish are better able to buffer adverse environmental fluctuations, growth-overfishing can lead to magnified fluctuations of abundance and decreased biological stability. If harvest has evolutionary consequences, these changes may be irreversible.”
But industries’ principal concerns rarely revolve around the future abundance of publicly-owned resources, the potentially irreversible impacts that they may be having on such resources or the public interest as a whole. With a very few exceptions—the fly fishing industry, which has long championed conservation, and elements of the outdoor industry, currently battling Utah’s 19th Century approach to wild lands use come to mind—industry is normally concerned with maximizing the income of industry members, regardless of the collateral damage caused.
That’s why tobacco companies shouldn’t regulate public health, oil and coal companies shouldn’t regulate clean air and clean water (but, right now, apparently do) and the fishing tackle and boatbuilding industries should not play a major role in managing fisheries.
Industries’ interests and the public interest are often just not the same.
However, the tackle and boatbuilding industries, in an attempt to advance their own interests, are holding the striped bass up as an example of effective fishery management, and are strongly suggesting that all popular recreational species should be managed like striped bass.
The industry apparently highlights striped bass because it is one of the few examples of states successfully rebuilding a marine fish stock, and the only example of the Atlantic States Marine Fisheries Commission, perhaps the most obvious example of concerted state management, accomplishing such rebuilding.
It is probably appropriate that the industry, in its efforts to roll back more than two decades of successful federal fisheries management efforts, are relying on a striped bass recovery that was completed a year before the Sustainable Fisheries Act of 1996 was adopted by Congress. In the years since the striped bass’ recovery—and in the years since the Sustainable Fisheries Act was signed into law—federal managers have successfully rebuilt 39 marine fish stocks, while the Atlantic States Marine Fisheries Commission has failed to rebuild even one.
Moreover, the striped bass stock, once ASMFC’s shining success, isn’t looking so good lately and, if some state managers get their way, it may soon be looking even worse.
A benchmark striped bass stock assessment released in the fall of 2013 suggested that the stock was in imminent danger of becoming overfished. Even so, it took ASMFC a full year to adopt management measures intended to reduce fishing mortality to the target level recommended in the benchmark assessment.
A stock assessment update released late in 2016 informed managers that, after one full year of reduced harvest, female spawning stock biomass stood at 58,853 metric tons, just 1.2 metric tons above the 57,626 metric ton threshold that defined an overfished stock, and more than 13 metric tons below the 72,032 metric ton biomass target.
Fishing mortality had been reduced to 0.16, exactly in line with the intent of the most recent Addendum to ASMFC’s striped bass management plan, which was
“to reduce [fishing mortality] to a level at or below the new target [emphasis added]”
Members of ASMFC’s Striped Bass Technical Committee advised managers that there is no meaningful statistical difference between the fishing mortality target of 0.18 and the calculated 2015 fishing mortality of 0.16, because
“the upper and lower bounds of the confidence intervals for both [fishing mortality] estimates would essentially overlap.”
Furthermore, they advised managers that 2016 fishing mortality would probably be slightly above the target, at or above 0.19.
Even so, and with the female spawning stock biomass hovering uncomfortably close to the “overfished” threshold, ASMFC’s Striped Bass Management Board began the process for increasing the striped bass kill.
According to a press release issued by ASMFC, such action was taken because of
“concerns raised by Chesapeake Bay jurisdictions regarding continued economic hardship endured by its stakeholders since the implementation of Addendum IV and information from the 2016 assessment update indicating fishing mortality is below the target.”
The fact that the Technical Committee advised that
“although the assessment is very good, it may not be able to distinguish between fishing mortality point estimates of 0.16 and 0.18”
wasn’t mentioned at all. Neither was the fact that the point estimate of 2016 fishing mortality exceeded the fishing mortality target.
Because that is the way striped bass are really managed--with little heed for the science, and economics the prime concern.
That’s just the way that the tackle and boatbuilding industries want all stocks to be managed—to benefit the industry, and not the public at large.
Which is why the public, and not the industry or their favored state managers, may prove to be the striped bass’ salvation.
Because striped bass anglers aren’t happy with the proposed harvest increase at all, even though they would be the alleged beneficiaries.
On the Water Magazine is probably the foremost angling publication along the striper coast, with regional editions covering the fishery from Delaware Bay up through New England. When it announced the possible harvest increase in its on-line edition, the response from striped bass anglers was one-sided and clear, with comments such as
“Once again the fisheries managers put the end user first rather than the fishery. I would like to know where the fishery has been successfully managed by these intellectually challenged individuals,” and
“Although the report indicates that the ‘…striped bass stock is not overfished..’ it is a very low bar that is being measured…The measured stock, 58,853 mt, is no where near the target…and projecting out, would take years to recover to the target…It is just amazingly short sighted to revisit the reductions which were only just recently implemented in 2015. It appears there is very little spine in the agency meant to properly manage the striped bass stock. [emphasis added]”
Along with the succinct, but nonetheless accurate
“No. It’s a stupid idea.”
Striped bass anglers seem to get it. Whether that’s because there is an institutional memory of the stock collapse of the 1970s and 1980s, which is passed down through the ranks by those of us who were there and remember, or whether it is because striped bass have always been viewed by anglers as something special, the largest and most challenging fish available to inshore anglers of the northeast coast, most seem to have a gut-level acceptance of the need for conservation to protect their beloved “striper.”
That pro-conservation attitude is reflected in the outdoor writers who cover the fishery. Recently, Todd Corayer penned an article entitled “Stripers should not be overfished; so give Max a call” in the Southern Rhode Island Newspapers. He urges readers to
“Please call Max Appleman immediately. Max is the Fishery Management Plan Cooridinator for the Atlantic States Marine [Fisheries Commission] and his phone number is 703.842.0740. Max is the man taking calls from people opposing or supporting a move the ASMFC is considering to increase the harvest of striped bass. Actually, they call it ‘liberalizing.’
“’Liberalizing’ is a wonderful word; grammatically correct, passively deceiving. To liberalize indeed conjures up thoughts of loosening a restriction, relieving something or someone of a burden. In this context, the ASMFC is feeling pressure from fishermen in the Chesapeake who want to catch more bass. They are using the arguments that under present data sets, stripers are not overfished or experiencing overfishing…So logically then, the Baymen protest, they should catch and take more. I say no…
“A friend sent a brief report about the addendum to the amendment with a one line observation: ‘Well, that sucks.’ I agreed and almost on moved [sic] to the next e-mail but that is precisely how bad ideas slide through the system.
“Fisheries management is front-loaded; if you wait for a public hearing six months into a government effort to let everyone know your big idea or an addendum to their addendum, the train will have already left the station. Your best intentions will be best served at the start of the process. Public comments all get read and analyzed and many get posted on a website somewhere but to effect change, we need to start at the beginning…
“Harvest numbers should not increase based on a few level years and a statement that mortality levels are lower than the threshold scientists determined. It seems clear that fishermen in these parts recognize have a goal of population abundance and not permission to take more and more.
“…if you have any inkling to see a beloved fish stay protected with very manageable regulations, this is the time to let your voice be heard.”
I never met Mr. Corayer, but I suspect that I’d like the guy.
He seems like most of the striper fishermen whom I know, folks who don’t seek to kill the last bass in the ocean. But unlike far too many, he also understands that striped bass fishermen need to get involved in the management process.
His comments about getting involved early show that he has a good understanding of how the management process works.
I urge everyone who cares about the striper to get up off their chairs and play a role in the fight.
But I also urge everyone, whether they fish for stripers or not, to consider one more thing.
Should all of our fisheries, including those currently managed by fisheries managers, be “managed like striped bass,” where a well-conceived management plan can be overthrown for the sake of a fistful of dollars?
Or should we insist that our fisheries managers all begin to think like striped bass fishermen, putting the resource first and, like Mr. Corayer, “have a goal of population abundance and [are] not [seeking] permission to take more and more”?
Should anyone ask, I know what my answer would be...
Thursday, February 16, 2017
If there is one constant in mid-Atlantic fisheries management, it is that restrictions on the recreational summer flounder harvest will always be controversial.
That is particularly true in 2017, after six years of below-average recruitment—the number of young fish entering the population—has caused , forcing the National Marine Fisheries Service (NMFS) to
As is typically the case, those who oppose NMFS’ action are attacking the science that underlies the agency’s decision to reduce recreational landings. The American Sportfishing Association (ASA), which represents the fishing tackle industry, “the decision is being based on an outdated benchmark stock assessment,” while railed against “‘fatally flawed’ MRIP data, [and] the inherent issues with NOAA’s trawl survey methodologies,” even though a gave the Marine Recreational Information Program a very favorable review.
This year the opponents of fluke regulation are claiming that a new study, prepared by biologists hired by a group calling itself the (SSFFF), justifies their criticism of the current stock assessment. found that “female summer flounder dominate the recreational catch; however…this does not hold below the legal size limit. On average, across all ports, dates, and depths, the sex ratio approximates 50:50 at 39 cm [15.6 inches], with males dominant in the size classes less than 39 cm and females dominant above 39 cm.”
They use the study to support the notion, expressed in , one of the founders of SSFFF, that “blame must be assigned to any management strategy that forces us to target spawning class females exclusively. It’s crazy, we’re talking biological suicide!” To avoid catching so many large females, opponents of the current regulatory approach suggest that “management strategies in the recreational fishery in the future should include the potential for a slot limit fishery” that established both a minimum and maximum size for fish that may be retained by anglers.
Proponents of such a “slot limit” argue that a slot that allowed anglers to keep smaller fish, and assure that males made up a significant portion of the recreational harvest, would better assure that enough large females survived to maintain the population at a sustainable level.
However, such argument runs afoul of two fisheries management principles: The need for a closed season to control harvest, and a measure of stock productivity known as “steepness.”
Season length comes into play because there are only three ways that fishery managers can limit anglers’ landings: size limits, bag limits, closed seasons or some combination thereof. As a rule, both anglers and the businesses they support consider a reasonably long season the most important management measure because it provides anglers more time to fish, which in turn results in more money flowing to angling-related businesses. There is no biological reason for recreational size limits to be as high as they are today; anglers could enjoy the same 14-inch minimum size that governs the commercial fishery, if they were willing to accept a much shorter season in exchange.
Proponents of a slot limit seem to forget that if anglers were allowed to retain smaller “slot” summer flounder (so far, no slot size has been proposed, but it’s reasonable to assume that any slot would bracket the point where males and females are equally represented in anglers’ catch), the season would have to be shortened to compensate for the greater number of legal-sized fish that would be caught.
And that’s where “steepness” comes in.
Like fishing mortality and spawning stock biomass, steepness is a parameter that fisheries managers must consider when setting annual catch limits. “the ratio of two recruitment levels; the recruitment obtained when the spawning stock is at 20% of its virgin level, and the recruitment at the virgin population level.” It is expressed as a number between 0 and 1; the lower the number, the more recruitment—the number of young fish entering the population—is dependent on stock size. A high steepness number, on the other hand, suggests that good recruitment can occur even when the spawning stock is relatively small.
Thus, proponents of a slot limit for summer flounder, who use the SSFFF study to justify their position, are actually contradicting themselves.
If the summer flounder population must include a large number of large females to guarantee good recruitment—that is, if summer flounder steepness is low—fishing mortality needs to be tightly constrained in order to maintain the large spawning stock necessary to maintain a healthy population. A slot limit, without a significantly shortened season, would allow anglers to kill too many fish.
On the other hand, if steepness is high enough to justify the higher fishing mortality that would result from a slot limit combined with the current season, then there is no need to assure that a large number of older females remain in the population, as good recruitment can result from a small spawning stock.
Whichever scenario turns out to be the right one, neither justifies a claim that the SSFFF study somehow negates the need to reduce fishing mortality today.
In fact, current science supports high steepness for summer flounder.
The determined that calculations based on such a high steepness number were “suspect,” and did not consider such figure in setting the permissible (threshold) fishing mortality rate. But even if the actual steepness figure for summer flounder is somewhat lower, that figure will still be high enough to assure fisheries managers that there is no need to increase the number of females present in the spawning stock.
Although, according to the benchmark assessment, the stock could actually tolerate a higher fishing mortality rate and smaller target biomass. Managers determined that “little gain…(<5%) was realized at fishing mortality rates higher than [the current threshold of] F35%=0.310," while the current target biomass and threshold fishing mortality rate provided a "buffer against short-term declines in recruitment," which is exactly the situation which faces the stock right now.
Thus, arguments that the SSFFF study has rendered to benchmark assessment obsolete, and that a new benchmark assessment, are not supported by science. The current assessment passed , and has been accepted by the eighteen PhD-level biologists that make up the . That should be a good enough endorsement for anyone.
This post first appeared in "From the Waterfront," the blog of the Marine Fish Conservation Network. "From the Waterfront" may be found at http://conservefish.org/blog/
This post first appeared in "From the Waterfront," the blog of the Marine Fish Conservation Network. "From the Waterfront" may be found at http://conservefish.org/blog/
Sunday, February 12, 2017
The National Marine Fisheries Service’s decision to reducethis year’s annual catch limit for summer flounder by 30% was met with howls of dismay from elements of both the commercial and recreational fisheries.
Although the decision was justified by six consecutive yearsof below-average recruitment, which has caused the spawning stock biomass todecline to just 58% of the target level, many fishermen’s knee-jerk reaction has been to attack the data underlying NMFS’ decision, rather than in trying to understand how that data was obtained and used.
Some of the most frequently-attacked data has been that developed by NMFS’ annual spring and fall trawl surveys, which survey the abundance of a wide array of species found off New England and the Mid-Atlantic coast.
A letter that the New York Sportfishing Federation sent to the Atlantic States Marine Fisheries Commission is typical. In it, the Federation asks that no reduction occur until a new stock assessment is completed. As part of its argument in favor of status quo regulations, it says
“We strongly believe that the data collected on the trawl surveys that were done by NMFS on their vessel “Bigelow” are grossly inaccurate. The trawl survey vessel is improperly equipped and their gear type and methods for harvesting summer flounder are inadequate, thus rendering this data useless for management purposes. [emphasis added]”
The Federation may well be right in saying that the NMFS vessel Bigelow’s gear is “inadequate” for the task of harvesting summer flounder. However, the Bigelow’s gear is not intended to harvest summer flounder, but to survey the health of the stock, and that makes a big difference when folks talk about the adequacy of the gear used.
While the Federation is a recreational fishing organization, commercial fishermen may have an even harder time in understanding the difference between trying to harvest and trying to survey. A recent and frequently-quoted piece published by the Center for Sustainable Fisheries criticized the NMFS trawl survey with respect to another flatfish, witch flounder, saying
“Fishermen have long maintained that there is a huge disconnect between what they see on the water and the conclusions derived from the NOAA surveys and stock assessments. Their claims have been dismissed as self-serving. Now it seems the fishermen have a strong case. On a recent bottom trawl survey, a typical industry net caught four times as many flatfish as the rig used on the government trawl survey...
“[A] boat was rigged to tow two nets simultaneously, each of the type used on the Bigelow, with one significant difference. One net was fitted with a rockhopper and the other had a chain sweep. Because different fish species behave differently, fishermen use a chain sweep, attached to the leading edge of the net and in contact with the sea floor, when targeting flatfish such as witch flounder. These fish hide in the sediment on soft bottom to evade predators. You will hear fishermen refer to fishing boats with rockhoppers as ‘hard bottom boats’ because those boats typically go after other species such as cod or haddock which tend to be found over rocky or gravel bottom.
“…[The Bigelow’s] exclusive use of a rockhopper has been a point of contention with the fishermen since the Bigelow commenced operations in these waters. Fishermen openly questioned its accuracy in estimating flatfish abundance. The survey work [comparing the two net types] has provided the evidence that their skepticism is well founded.”
That was the fishermen’s view. In reality, the comparison between the two nets provided no such evidence at all.
However, the comments of both the New York Sportfishing Federation and the Center for Sustainable Fisheries does prove that the folks representing those organizations just don't understand the survey process.
When a fisherman pulls a trawl, such trawl is configured to maximize the number of the target fish species caught, minimize time on the water and so reduce expenses, and generally allow the fisherman to operate as efficiently as possible. But when a scientist pulls a trawl, such trawl is configured to catch a representative sample of all the fish, in a consistent and repeatable manner, at each predetermined area where sampling takes place.
The goal of the NMFS survey is not to catch as many of each species as possible; in fact, catching too many fish can slow down and ultimately degrade the sampling process. NMFS spells that out quite clearly, saying
“we want consistently comparable catches, from which we derive a whole series of measurements and samples collected from fish and invertebrates captured on each tow.”
NMFS notes that when too many fish are caught by the trawl
“The time required to sort and process the catch increases, which adds to the time required to conduct the work—either increasing the cost or decreasing the amount of geographical area we can cover. Also, large catches must be subsampled to estimate what has actually been caught during each tow. The combined effects potentially increase error associated with both sampling (reducing the number of stations) and subsampling.”
And that’s what fishermen are seemingly unable to understand. The fact that a net may be configured to catch the most fish doesn’t mean that such net would be the best one to use in a survey. Such a net might very well catch so many fish that the survey quality would decline.
The purpose of the survey is not to catch as many fish as possible, but to determine relative abundance. As NMFS states in the operating protocols for the Northeast Multispecies Bottom Trawl Survey,
“Abundance estimates obtained from this survey are relative abundance indices rather than absolute abundance indices because catch efficiency of the sampling gear is less than 100%. Relative abundance indices are comparable through time because survey catchability is held constant through standardization of gear, vessel, and methodology.”
Thus, even if the NMFS survey gear catches, at best, only 25% of the flatfish that are present, as the Center for Sustainable Fisheries’ comments suggest may be true, so long as it consistently catches 25% of the fish available, the gear used by the Bigelow is proper for its purpose, and not inadequate at all.
The only thing that remains inadequate is many fishermen’s knowledge of how surveys are done, and what information the trawl data is meant to convey.
Such fishermen require a new, improved understanding far more than NMFS requires a new stock assessment of summer flounder.
Thursday, February 9, 2017
Fisheries management is not an exact science.
Although biologists are constantly refining their stock assessments and population models, there are still many sources of uncertainty.
Some of them fall into the category of “scientific uncertainty.” Such scientific uncertainty applies to all of the important parameters, such as stock size and the number of young fish recruited into the stock each year. Biologists deal with such uncertainty by specifying a “confidence interval,” stated as a probability that the actual stock size, recruitment figure or other parameter is included in a particular range of values.
The provides a good example. available to them, and the assessment is updated each year, as new information becomes available. Even so, the confidence intervals used in summer flounder management are fairly broad.
Thus, while the estimated the spawning stock biomass to be 36,240 metric tons (mt), it also recognized the uncertainty in that estimate, stating that “The 90% confidence interval for [spawning stock biomass] in 2015 was 32,605 to 44,425 mt,” meaning that there is a 90% probability that the actual biomass fell somewhere between those two numbers.
Obviously, management measures that are appropriate for a stock of 36,000 mt are a little more restrictive than they would need to be if the stock size is closer to 44,000 mt, but not restrictive enough if the stock size be closer to 32,000 mt. However, such measures would represent a statistically defensible way to strike a balance between those two extremes.
Because some degree of scientific uncertainty is inevitable, , the threshold where overfishing begins. Instead, the Science and Statistics Committee (SSC) of each regional fishery management council must address scientific uncertainty by establishing an allowable biological catch (ABC), an upper limit on landings which represents the OFL, reduced by a buffer that allows for such uncertainty.
In the case of 2017 summer flounder harvest, such buffer reduced a 7,600 mt OFL to a 5,125 mt ABC, making it far less likely that overfishing will occur.
Scientific uncertainty is only half of the problem that managers face when setting annual catch limits (ACLs); they must account for management uncertainty as well. Unlike scientific uncertainty, which must be considered when setting ABCs, .
Management uncertainty can arise in a number of ways. Harvest might not be accurately calculated; that’s a particular problem in recreational fisheries, where harvest is estimated based on a survey, and less of a problem in commercial fisheries, where landings must be reported. Managers can never be completely certain that the regulations that they adopt in any given year will prevent overfishing. Even if the regulations opposed are adequate, there is no guarantee that all fishermen will obey them.
Thus, management uncertainty can have a real impact on the success of management measures. However, because accounting for uncertainty will inevitably reduce ACLs, regional fishery management councils are often reluctant to do so.
That became a particular problem for the Gulf of Mexico Fishery Management Council (Gulf Council) a few years ago, which couldn’t keep recreational fishermen from exceeding their ACL for red snapper.
, with the exception of 2010, when the catastrophic oil spill that occurred after BP’s Deepwater Horizon oil well blew up kept fishermen off the water.
but refused to adopt the 20% buffer recommended by its SSC. It argued that a new benchmark stock assessment and better methods of gathering recreational data rendered such a large buffer unnecessary.
A group of commercial fishermen, concerned about the damage that constant recreational overharvest was doing to the stock, sued NMFS in federal court, seeking a decision that would compel the agency to hold anglers accountable for their repeated overages.
The commercial fishermen won the lawsuit.
The court that decided the case, , said that accountability measures (AMs) “can and should be used to address management uncertainty. NMFS must disapprove and return for revision any Council proposal that does not contain adequate AMs.”
It quoted a section of the administrative record which stated that “Considerable uncertainty exists in projecting season estimates given variability in average weights, catch per day, and implementation of incompatible state regulations,” and ultimately found that “NMFS had a statutory duty to…require whatever accountability measures are necessary to constrain catch to the quota.”
NMFS responded by implementing the 20% buffer that the Gulf Council had previously rejected, in order to avoid further recreational overfishing.
Now, management uncertainty may be undermining the effort to manage summer flounder.
Everyone admits that there is a serious management uncertainty issue in the recreational summer flounder fishery. The issue was well-described in , Director of the New York State Department of Environmental Conservation’s Marine Division, to the Chair of the Atlantic States Marine Fisheries Commission’s Summer Flounder, Scup and Black Sea Bass Management Board (Management Board):
“There seems to be a poor relationship between the recreational measures (derived from calculations based on the [Marine Recreational Information Program]) and the performance (as estimated by [such program]). Regional summer flounder recreational management has been in place for the last 3 years (2014-2016). During this period regulations adopted by each region have not changed with the exception of NJ’s portion of Delaware Bay…Under consistent measures there are numerous factors that may influence recreational harvest in a state, with weather and fish availability to anglers among the most important. Harvest estimates are in turn influenced by the actual magnitude of the harvest and the variability inherent in a survey…Under 3 years of consistent regulations from 2014-2016, coastwide harvest estimates in numbers of fish have ranged from 1.6-2.5 million fish, varying as much as 50% between years. When we consider a smaller geographic scale, this variability increases to 66% between years in the CT-NJ region, and an average of 139% at the individual state level. It is difficult to say how much of this variability is due to estimation vs. actual harvest magnitude.”
Given such a high degree of management uncertainty, and considering the court’s decision in Guindon v. Pritzker, one might expect NMFS to establish a recreational ACL somewhat lower than the ABC, in order to create a buffer against such uncertainty.
However, in (MAFMC) and Management Board, the MAFMC’s Summer Flounder, Scup and Black Sea Bass Monitoring Committee advised that “The Monitoring Committee recommends no reduction from the commercial ACLs to the [Annual Catch Targets] in 2017-2018 to address management uncertainty…The Committee also recommends no reduction from the recreational ACLs to the recreational [Annual Catch Targets] for 2017-2018…”
The lack of a buffer for management uncertainty helped anglers in 2016. Because angling effort was probably underestimated in 2015, were surprisingly low, which , even though .
However, when , such regulations did not adequately constrain recreational landings. As a result, in 2017, even though .
in the recreational fishing community, hostility that might have been avoided had managers been willing to admit that the 2015 harvest estimates were probably too low, and incorporated a buffer for management uncertainty into the 2016 regulations.
On the other hand, had such a buffer been adopted for 2016, many members of the recreational fishing community probably would have protested that…
That’s why it’s difficult to properly account for management uncertainty. Fishery managers know that it exists, at some level, in every recreational fishery; they also know that, eventually, it will probably result in anglers overfishing their ACL.
However, because accounting for management uncertainty leads to smaller recreational ACLs, which in turn leads to unhappy recreational fishermen, managers are reluctant to put such constraints on landings even when, as was true with red snapper, anglers regularly overfish their ACLs.
A court decision, such as Guindon v. Pritzker, can force managers’ hands, but managers shouldn’t have to be forced to take needed actions. By incorporating a buffer for management uncertainty into each year’s ACLs, fishery managers better assure that regulations will be consistent from year to year.
Consistent regulations, even if they result in somewhat smaller ACLs, tend to strengthen anglers’ faith in fisheries management, while regulations that change every year, without seeming cause or direction, lead anglers to question managers’ decisions.
Since fishermen are far more likely to obey regulations that they believe in, properly accounting for management uncertainty is an important, yet too often ignored, part of the management process.
This essay first appeared in “From the Waterfront,” the blog of the Marine Fish Conservation Network, which can be found at http://conservefish.org/blog/