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.”
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.
-----
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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