Sunday, February 21, 2021

STRIPED BASS AMENDMENT 7--NAVIGATING THE PID: PART III, MANAGEMENT TRIGGERS AND REBUILDING TIMELINES

In the last two editions of One Angler’s Voyage, I discussed a couple of issues raised by the Public Information Document for Amendment 7 to the Interstate Fishery Management Plan for Atlantic Striped Bass (PID), the proper Goals and Objectives for the striped bass management plan, and the biological reference points needed to achieve them.

In today’s blog, we’ll look at the third face of that issue:  When fishing mortality begins rising too high, and/or the spawning stock biomass falls too low, how should managers respond?

I’m going to begin that inquiry with an observation:  Fish can do well without fishermen, but fishermen, and fishing industries, can’t survive without fish.  

Maintaining the long-term health and sustainability of the striped bass stock ought to be the first priority of the Atlantic States Marine Fisheries Committee’s Atlantic Striped Bass Management Board.  While the Management Board can reasonably try to avoid unnecessarily inconveniencing the recreational and commercial fishing industries, it should never compromise the needs of the striped bass stock in its efforts to do so.

Fishery managers must always remember that Mother Nature doesn’t—and can’t—compromise.  The striped bass’ biological needs are just that—needs—and the stock cannot thrive if those needs aren’t met.

A management strategy that slows, but does not halt, the decline of the stock, in order to accommodate the short-term economic concerns of stakeholders, is a strategy that is destined to fail in the long term.  Stocks can’t be overfished back to health.  The failure to rebuild a stock when rebuilding is called for, in order to placate the fishing industry, only sets up both the stock and the stock-dependent industry for hard times the next time the bass faces adverse conditions on the spawning grounds and/or in the sea.

With that in mind, let’s look at the management triggers.  The current triggers, contained in Amendment 6 to the Interstate Management Plan for Atlantic Striped Bass, address three different issues:  fishing mortality, female spawning stock biomass, and the recruitment of new fish into the population. 

Of the three, fishing mortality is by far the most important, in part because controlling fishing mortality is directly related to maintaining the spawning stock biomass at acceptable levels, and in part because it is the only one of the three factors that the Management Board can directly control.

The last benchmark stock assessment notes that if female spawning stock biomass is to be maintained at its target level, fishing mortality must be constrained to its target level as well.  Yet, while fishing at or below the target fishing mortality level might be necessary to achieve the biomass target, that’s not the whole story.  Striped bass abundance is dependent upon two completely unrelated factors.  One is the number of fish being removed from the stock; that’s where fishing mortality comes in.  The other is the number of new fishing recruited into the stock, and fishing mortality doesn't affect that at all.

Many anglers think that if the spawning stock biomass is high, the number of juvenile bass produced by those females each year will be high, too.  That’s not how things work.  There is no clear relationship between the size of the spawning stock and spawning success.  

Biologists measure such stock-recruit relationship with a parameter they call “steepness,” which is

“a ratio of 2 recruitment levels:  the recruitment obtained when the spawning stock is at 20% of its [unfished] level, and the recruitment at the [unfished] level.”

The higher the number obtained by dividing the number of fish recruited into a stock fished down to just 20 percent of its unfished level by the number of fish recruited into an unfished stock, the less that spawning success is dependent upon the size of the spawning stock.

The model used to produce the most recent benchmark stock assessment for bass used a steepness value of 1, which assumes that there is no stock-recruitment relationship at all.

Normally, that would be good news, because it would mean that striped bass were a very resilient species, that could be quickly rebuilt even if spawning stock biomass fell to very low numbers.  Unfortunately, in the case of striped bass, that resilience is tempered, and even controlled, by another, external factor:  Weather.

In my last blog, I quoted Dr. Michael Armstrong, Assistant Director of the Massachusetts Division of Marine Fisheries, who noted during an American Sportfishing Association-sponsored webinar last July, that

“Recruitment is striped bass is highly variable…When you have a series of lows…we start seeing spawning stock biomass eroding, and that’s exactly what has caused the [current] erosion of spawning stock biomass, it’s these poor year classes.  It’s primarily not fishing, it’s primarily environmental causes.  And the primary cause is…the water regime in Chesapeake Bay.  When you have flood springs, you get bad recruitment.  When you get really dry springs, you get bad recruitment.  When you get nice cool, wettish springs, you get big year classes…”

Then he uttered the words that ought to control the entire management trigger discussion:

“We have to husband the big year classes along the best we can.  The only way to do that is to keep [fishing mortality] low.  [emphasis added]”

And the best way to do that is to adopt more restrictive management measures as soon as fishing mortality gets too high.

Two of the current management triggers attempt to do just that.  Management trigger 1, which kicks in when the stock becomes subject to overfishing, says

“If the Management Board determines that the fishing mortality threshold is exceeded in any year, the Board must adjust the striped bass management program to reduce the fishing mortality rate to a level that is at or below the target within one year.”

Taking quick action to avoid overfishing makes sense, because fishing above the threshold target level doesn’t only mean that it will be difficult, if not impossible, to maintain the biomass at or below the target level.  It means that the stock is likely to fall below the biomass threshold, and become overfished at some point in the future, if no action is taken.

And the Management Board should never allow the stock to become overfished again.

But if it is doing its job diligently and well, the Management Board should never allow overfishing to occur. 

Sometimes, inevitably, some combination of factors—perhaps a strong year class of fish, perhaps unexpectedly good weather, perhaps something different—will result in more people fishing, or the bass being easier to catch, and cause fishing mortality to rise above the target over the course of a season.  That should be expected, and not be a cause for concern.

But if fishing mortality doesn’t drop back to or below the target in the following year, there could be something inherently wrong with the management process.  That’s where management trigger 3 kicks in:

“If the Management Board determines that the fishing mortality target is exceeded in two consecutive years and the female spawning stock biomass falls below the target within either of those years, the Management Board must adjust the striped bass management program to reduce the fishing mortality rate to a level that is at or below the target within one year.”

Again, it’s a prudent measure.

If fishing mortality gets a little too high when the stock is above the biomass target, no real harm is done, and the Management Board can safely defer action.  But if fishing mortality is still too high after the biomass falls below target, then that fishing mortality is driving down abundance, and needs to be addressed before the biomass declines to the point where the Management Board, perhaps hampered by adverse conditions on the spawning grounds, will have real difficulty rebuilding it without resorting to very restrictive measures.

It’s always easier to fix a problem when it first appears, rather than waiting until things approach crisis levels before taking action.

Of course, not every Management Board member agrees.  The “Work Group” report that preceded the creation of the PID noted that

“Some stakeholders support the 1-year requirement for change while others believe that it promotes ‘knee-jerk’ reactions that might not always be necessary.  [emphasis added]”

That’s interesting language, which says a lot about why the Management Board, and more generally, the ASMFC, has such a poor record of maintaining fish stocks at healthy and sustainable levels. 

It inherently admits that imposing additional management measures are often needed, but also reflects the views, held by too many Management Board members, that it is worse to impose restrictions that “might not always be necessary” than it is to fail to adopt restrictions that are needed to maintain the health of the striped bass stock.  In their view, it is better to delay action in order to avoid the occasional, unnecessary restriction, even if that increases the risk to the fish that they are obligated to manage and conserve.

That bias, which favors continued harvest in the face of uncertainty, and underlies the PID’s emphasis on “management stability” and “flexibility,” has hampered fisheries management at the ASMFC for many years.

Board delay, continued overfishing, and a few years of poor recruitment could leave the striped bass stock in a pretty bad place.  A quick response to excessive fishing mortality is the only way to help assure the abundance of the stock—even if it doesn’t provide for “management stability.”  Thus, management triggers 1 and 2 should remain unchanged.

Things get a little trickier when we start talking about spawning stock biomass.  

Amendment 6 contains two management triggers that deal with that, too, and both are similar to the triggers that address fishing mortality.  One requires a rebuilding plan, not to exceed ten years in duration, if the stock becomes overfished; the other requires that the same rebuilding plan be put in place if spawning stock biomass falls below target for two consecutive years, and fishing mortality rises above target in either year.

Here’s the problem:  While the Management Board clearly should intervene when spawning stock biomass declines, its ability to rebuild that biomass will always be limited by the number of young bass recruiting into the stock.  A mason can’t rebuild a wall without bricks; a fishery manager can’t rebuld a stock without fish.

The farther the stock declines, the harder it will be to rebuild if, due to adverse conditions in the spawning rivers, recruitment remains low (if spawning conditions are good, on the other hand, the lack of a stock-recruitment relationship should allow for a quick and successful recovery).

That means that the Management Board ought to do everything in its power to keep the stock from becoming overfished.  If the stock does become overfished, as it is right now, it is only because the Management Board failed to intervene in time, and didn’t adequately reduce fishing mortality while there was still a chance to effectively do so.  Management stability would have prevailed over management success.

Even in a period of poor recruitment, the striped bass stock can be rebuilt within ten years, if the Management Board summons the will to do so.  Amendment 3 to the Interstate Fishery Management Plan for Atlantic Striped Bass was adopted in late 1985, in the depths of the striped bass collapse, when recruitment was at or near historic lows.  In 1995—just 10 years later—the stock was declared completely rebuilt, although it’s worth noting that such rebuilding was only to what we’d now consider the biomass threshold, not the target.

Yet it’s important to note that even to get there, the Management Board had to resort to very restrictive measures, which gave near-full protection to the “large” (today, we’d deem it below average) 1982 year class, and every year class that came after.  Amendment 3 contemplated removing no more than 5 percent of the protected year classes from the population each year, a fishing mortality rate of just 0.051; the current fishing mortality rate target of 0.197 allows more than three times as many—roughly 17 percent—of striped bass to be removed from the stock each year.

So nipping a stock decline when it first manifests itself, rather than letting things get worse for a few years, can help stakeholders avoid a lot of future pain.

That’s why management trigger 4, which requires rebuilding when spawning stock biomass falls below target in consecutive years, and fishing mortality rises above target as well, makes sense.  It provides for an early, easier fix, instead of a long, difficult, and painful slog back from an overfished condition.

So when talking about current management triggers 2 and 4, both make sense, and both ought to remain as they are.

That gets us to the most difficult issue, management trigger 5, which addresses recruitment failure.  It reads

“The Management Board shall annually examine trends in all required Juvenile Abundance Index surveys.  If any JAI shows recruitment failure (i.e., JAI is lower than 75% of all other values in the dataset) for three consecutive years, then the Management Board will review the cause of the recruitment failure (i.e., fishing mortality, environmental conditions, disease, etc.) and determine the appropriate management action.  The Management Board shall be the final arbiter in all management decisions.”

Here, in management trigger 5, we find someting that probably does need to change.  If we look at the Maryland striped bass juvenile abundance index, we find that such index would have to be below 4.24 for three consecutive years before the trigger is tripped.  That only happened once in the 64-year history of the index, during the years 1983-1986, when the stock was just beginning to claw itself out of its prior collapse.

And that shows the weakness of management trigger 5; it would only have been tripped in 1985, after Amendment 3 had been adopted.  If it had been in place back in the 1970s, it would not have prevented the stock collapse, just as it didn’t prevent the stock from becoming overfished today.  The question is, what would make it better? 

Perhaps if it triggered when a three-year rolling average, rather than three consecutive years’ indices, fell below the twenty-fifth percentile, it would be more effective. 

If that were the case, the trigger would have been tripped (again, if it had been in effect) in 1981, when a three-year average of just 2.40 might have started rebuilding just a little earlier, and perhaps protected more of the critical 1982 year class.  It’s far from impossible that, if such rolling average was in effect, management trigger 5 would also be tripped at the end of this year, as the Maryland JAI was dismal enough in 2019 and 2020—3.37 and 2.48, respectively—than anything lower than a still sub-par 6.8 for 2021 would be low enough to require action.

And requiring action, of course, should be another change.  As currently written, management trigger 5 does not require management action, even if recruitment failure occurs.  Allowing a Management Board that is wedded to the concept of “management stability” to be “be the final arbiter in all management decisions” virtually guarantees that nothing will be done.

Thus, with respect to management trigger 5, change is needed.  A rolling average that falls below the 25th percentile of the relevant juvenile abundance index would be a step in the right direction, as would language that requires Management Board action.  I’ll leave the precise wording of the needed changes to the scientists and statistical experts, who actually know how to calculate such things. 

But change, of some sort, is required, the sort of change that forces managers to respond to declining recruitment trends, and compels them to act before declining recruitment translates itself into a depleted spawning stock.

That leaves only one issue:  How long should the Management Board have to rebuild the spawning stock?

Management triggers 2 and 4 both say that if either one is tripped,

“the Management Board must adjust the striped bass management program to rebuild the biomass that is at or above the target within the timeframe established in Section 2.6.2 [of Amendment 6]”

That section says that if rebuilding is required

“the Management Board will determine the rebuilding schedule at that time.  The only limitation imposed under Amendment 6 is that the rebuilding schedule is not to exceed 10 years.”

So is 10 years an appropriate rebuilding period?  The PID asks

“What is more important, rebuilding the stock quickly, or mitigating the impact to fisheries?  In other words, do you prefer significant changes to rebuild the stock quickly, or smaller incremental over time to gradually rebuild the stock.”

Those questions were inadvertently answered by MichaelWaine, the ASMFC’s former Fishery Management Plan Coordinator for striped bass,in August 2014, when he (in my opinion, very wrongly) sought to convince theManagement Board to ignore their clear obligation under management trigger 4,and not initiate a rebuilding plan for the striped bass stock.

The bass are suffering the consequences of that advice today.  But what Waine said still remains relevant.  It was

“Management trigger 2 [sic] in Amendment 6 says that you need to rebuild the [spawning stock biomass] back to its target over a specified timeframe that should not exceed ten years.  I think that there is sort of a combination of things happening.  The board is acting to reduce [fishing mortality].  Through that action we see the projections showing that [spawning stock biomass] will start increasing towards its target, but we’re uncomfortable with projecting out far enough to tell you when it will reach its target because the further on the projections we go the more uncertainty that is involved.  [emphasis added]” 

In some ways, Waine wasn’t wrong.  The degree of uncertainty does increase over time, and it’s much more difficult to predict where the spawning stock biomass is going to be ten years from now than it is to predict where it will be in just two or three years.  That’s why “management stability” is such a dangerous concept—if the Management Board sets regulations that don’t seem to work, it should be willing to make course corrections when and as needed, to counter the effects of past uncertainty, and not maintain ineffective measures in the name of stability.

But where Waine went wrong was first, and most obviously, in assuming that the actions taken in 2014 would initiate rebuilding—in fact, the stock continued downhill—and then in using uncertainty as an excuse for ignoring the 10-year rebuilding deadline in Amendment 6, instead of as a reason for setting a goal, and then making mid-course corrections to assure that such goal was achieved.

As mentioned earlier, history has demonstrated that even a collapsed striped bass stock can be rebuilt within 10 years.  Yes, there is uncertainty about how to get it done by that deadline, but assuming that the Management Board is willing to elevate the needs of the bass above its desire for ineffective, but stable, regulations, there's nothing that new regulations can't cure.

Think about it.  If uncertainty m akes it difficult to develop a 10-year rebuilding plan, why should anyone believe that it would be easier to rebuild the stock in 15 or even 20 years, when uncertainty would be further compounded by time?

Human nature also needs to be considered.  When presented with a firm deadline, people can usually figure out how to get a job done, even if it might be unpleasant to do so.  But when faced with a choice of making a decision to rebuild a stock, and in doing so, suffer the vitriol spouted by temporarily inconvenienced stakeholders, or putting off the hard and unpleasant decisions off for another day, fisheries managers—particularly at the ASMFC—will almost always choose the latter course.

Consider the actions of the ASMFC's Tautog Management Board.  It knew that tautog were overfished in 1996, and had a pretty good idea how to fix the problem back then.  But because doing so would cause a lot of political pushback, it hemmed and hawed and tried to find a way to put off needed measures for more than 20 years.  Nothing resembling an effective tautog management plan was adopted until 2017—fully 21 years after the problem was first recognized—and even that plan will allow for overfishing in Long Island Sound until 2029.  No rebuilding timeline has yet been established.

It would take an optimist—or a fool—to believe that striped bass would fare any better if the 10-year rebuilding deadline was replaced with a longer rebuilding timeline—or with no deadline at all.

Thus, with respect to rebuilding, the 10-year deadline must be retained.

In the end, the right answer to all of the issues—both the management triggers and the rebuilding timeline—boil down to the needs of the fish, and to the foibles of fishery managers.  Prompt responses to problems with the stock will keep small issues from evolving into crises; taking away mangers’ ability to delay taking action will better assure that meaningful actions are taken.

And actions that help maintain striped bass abundance will, in the end, be best not only for the fish, but for fishermen and the fishing industry.

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On Thursday, One Angler’s Voyage will move on to the next important issues in the PID—conservation equivalency and accountability.  Unlike the topics discussed so far, those are issues where significant changes to the management plans are not only justified, but sorely needed.

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