Fisheries don’t collapse all at once. Instead, they
telegraph their distress with signals that may be subtle at the start, but grow
more insistent as stocks decline.
Often, at least in the case of migratory stocks, the first
sign of trouble might be a contraction of the fish’s range. On the East Coast
of the United States, most migratory inshore species have centers of seasonal
abundance. There is a core summer range, where the fish feed and are most
abundant after their northward migration, and there is typically a core winter
range, where they escape the worst of the cold.
Striped bass provide a good example.
Although scattered fish may appear anywhere along the coast
during the summer, the species’ core summer range extends from eastern Long
Island to southern Cape Cod, and includes both Block Island and the Elizabeth
Islands off Massachusetts. Even when the striped bass population was at its
lowest ebb during the early 1980s, fishermen could often find significant
concentrations of fish, including some very large individuals, around Block
Island, the outer Cape Cod beaches, and elsewhere in that core range, at a time
when it was extremely difficult for anglers to locate even one bass anywhere
else.
But when an increasing population creates more competitive
pressure, fish begin to spread out from the core into the extremes of their
range. Thus, Maine can see very good striped bass fishing when the stock is
healthy but, because it is also the first state to feel the effects of a
shrinking population, it is a bellwether for stock decline.
The November 2011 meeting of the Atlantic States
Marine Fisheries Commission’s Atlantic Striped Bass Management Board (Bass
Board) illustrated how that works. An update to the striped bass stock assessment had
just been released. It advised that the population was declining, and would
become overfished within six years.
Massachusetts biologist Gary Nelson, who was presenting the
assessment update, explained, “The striped bass stock is contracting [its
range] because of getting small, fish tend to do that. They like primary
[range] and then if the population is too big, they start to expand [their
range]. Maine is at the edge of the distribution. When the population is going
down, you’re going to see fewer fish there simply because of that impact.”
Unfortunately, the Bass Board didn’t heed the warning
signs, and the most recent benchmark stock assessment found that
the stock had, in fact, become overfished by 2017.
A change in the size of fish caught, or the absence of
large or small fish in a population, can also be a sign of future problems. It
is well known that fishing can lead to truncation of the age and size structure of a
fish population. Thus, when fishermen begin encountering fewer older
and larger fish than they had before, it is a good indication that fishing
mortality has increased, perhaps to unsustainable levels.
The health of a stock is also threatened when there are too
few young fish entering the population to replace the older individuals removed
by both fishing and natural mortality. A stock of fish composed mostly of
larger individuals may entertain anglers for a brief time, but at the risk of
eventual, and likely, collapse. Both the collapse of the Atlantic striped bass stock in the late 1970s and
early 1980s, and the collapse of the southern New England/Mid-Atlantic stock of winter
flounder twenty years later, were preceded by long periods of
recruitment failure that created declining populations made up largely of older
individuals.
As stocks enter deeper declines, fish become harder for
fishermen to find, and scientific assessments eventually reveal that the stock
is either overfished, experiencing overfishing or, as with the 2011 striped
bass assessment, at least well on the way to crossing one or both of those
thresholds.
Unfortunately, fishermen, whether recreational or
commercial, rarely heed the first signs of trouble. Too often, particularly
when short-term economic consequences might ensue, they tend to be like
children whistling as they walk past a graveyard, trying to deny their fear of
the ghosts and ghouls that might be residing therein; instead of recognizing
and addressing impending threats to a stock, fishermen often aggressively deny
that any such threats exist.
That can have dire consequences for the fisheries involved,
for while ghosts and ghouls don’t really exist, threats to many heavily
exploited fisheries are all too real, and they can cause very serious harm if
ignored.
I was reminded of that once again when I attended the most
recent meeting of New York’s Marine Resources Advisory Council (MRAC). One of
the topics on the agenda was the emergency management action taken by the Bass Board at
its May meeting, which set a maximum size of 31 inches for striped bass,
effectively reducing the 28- to 35-inch slot limit in place along most of the
coast to a narrow, 28- to 31-inch slot. Such action was taken to reduce
recreational landings, which spiked in 2022, to more sustainable levels.
Recent data developed by fishery managers makes it clear
that the striped bass stock is experiencing some serious problems. The stock,
to the best of anyone’s knowledge, remains overfished, although the spawning stock has
been expanding slowly, and it’s likely that spawning stock biomass will creep above the biomass threshold at some point
this year.
But that will probably be only a temporary reprieve.
In Maryland’s portion of the Chesapeake Bay, which is the
single most important striped bass spawning ground, the Maryland juvenile striped bass abundance index (JAI) is
crashing. The average JAI for 2019 through 2022 is the lowest four-year average
in the 65-year history of the Maryland survey; even during the early 1980s,
when the striped bass stock had collapsed, no four-year period ever quite
reached that nadir.
Cold winters and cool, wet springs are usually needed to
produce strong year classes of striped bass. The winter of 2022-23 was
unusually warm, and was followed by a warm spring that saw low water flows in
the Chesapeake tributaries. Such conditions set the stage for what will
probably be another very low JAI.
That’s going to leave a big hole in the striped bass age
structure, with at least four, and probably five, year classes largely absent
from the population. This year, one of the things that I’m noticing, and that
I’m hearing from others, is that fish less than 24 inches or so in length have
been scarce in most places this season.
That’s not a good sign.
Yet those who stand to be the most heavily impacted by the
decline in striped bass abundance, commercial fishermen and owner/operators of
for-hire vessels, seem to be trying very hard to convince themselves that the
striped bass stock is not facing an imminent problem.
One MRAC member, who operates a charter boat on eastern
Long Island, seemed almost stunned by the thought that striped bass abundance
will, almost inevitably, decline. He kept talking about how many fish he was seeing
now, noting that he was catching bass of all sizes “from about 24 inches up.”
He effectively acknowledged that his customers weren’t catching striped bass
any smaller than that, but couldn’t connect the current lack of small fish with
a future decline in the spawning stock. Instead, he asked the rhetorical
question, “Are you telling me that when the 2015s are gone, there won’t be any
striped bass?” and then shook his head and declared “I don’t believe that.”
Another for-hire operator in the audience rose to say that
one of his closest friends was a Maryland biologist who did striped bass work,
and who supposedly told him that environmental conditions in the Maryland area
were so bad that “we can forget about Chesapeake Bay.” He went on to assert
that ocean conditions were changing, waters were getting warmer farther north,
and somehow—he didn’t try to explain the mechanism involved—the bass will end
up doing just fine, without the need for the emergency action, as other fish
from other, unnamed places replaced those spawned in the Chesapeake Bay.
It was magical thinking at its best.
The only problem was that magic, like ghosts and ghouls,
isn’t real, while spawning failure in Maryland’s waters is.
I eventually spoke, supporting the emergency measures, and
spent a little time comparing the current Maryland spawning data with that
which was developed 45 years ago, when fishery managers failed to respond to
poor spawning success (the Bass Board had no legal authority to take binding
action back then) and the bass stock quickly collapsed. I was only citing the
JAI data and referencing historical facts, but out in the audience the head of
one of New York’s largest party and charter boat organizations apparently
didn’t want to hear it; he made a loud, exasperated noise, quickly stood up,
and walked out of the room.
At that point, a commercial MRAC member tried to assure
everyone that the problem was with the data, not the striped bass, questioning
the accuracy of the Maryland JAI, the stock assessment, and the recreational
landings data from 2022. To him, there was no such thing as good fisheries
data; it was all nothing but guesses. He declared that the striped bass were
doing fine, and no mere numbers were going to change his mind.
Other people took similar tacks, arguing that the 2022
recreational landings estimate was “just a single data point,” suggesting that
the Marine Recreational Information Program data was
wrong, and that emergency action could not be justified unless the validity of
that data could be confirmed, perhaps by fishing for another year under the
same 2022 rules. There was a certain irony in their words, as on one hand, they
argued that no emergency action was needed, as they were catching more bass now
than they had in years, and on the other hand, they argued that the data
showing them catching and keeping so many more fish was somehow suspect.
As the discussion ended, another long-time commercial
fisherman declared, “The striped bass will be here after you’re gone.” He
offered no facts to support his opinion but still, we can only hope that he’s
right.
More recently, the Montauk Boatmen and Captains Association
posted a petition on Change.org, challenging the Bass
Board’s emergency action. The petition notes that “more than 75% of our charter
boat fleet focuses the bulk of their season on striped bass fishing…Striped
bass fishing is truly the ‘bread and butter’ for most of our for-hire fishing
fleet.” The petition then goes on to characterize the emergency measures as
“drastic, unreasonable, and unnecessary,” and “preposterous” as well.
But it never explains why, at least from the bass’
perspective.
Instead, the objections to the emergency action were
couched in purely economic terms. The state of the striped bass stock was never
mentioned. It was almost as if the fleet was trying to convince itself that if
fishery managers took care of their economic concerns, the bass would somehow
take care of themselves.
Unfortunately, biology doesn’t work that way. Fishermen
can’t catch fish, whether for sale or for pleasure, if those fish have never
been spawned. Overfishing will not lead to a rebuilt stock. Fishing mortality
must be reduced to a level that, given current recruitment levels, allows the
stock to rebuild.
Fishermen can tell themselves that the emergency measures
aren’t needed to rebuild striped bass. They can try to make themselves believe
that the bass are doing just fine. But peer-reviewed science, and the bass
themselves, are telling us something very different.
We would all do well to listen.
Or we could find ourselves whistling past a very different
sort of graveyard.
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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/
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