If you spend any time at all around fishery management
meetings, you’re already familiar with the “not me” syndrome.
It takes a number of forms, but in the end, they all share
one common trait: When measures to increase
the abundance of some species of fish—any species of fish—are proposed, a
fisherman will stand up and say “Don’t put more restrictions on me! I’m not the problem! If you want to have more fish, you have to do
something about the [fill in the blanks]”
Exactly what species, or oceanic condition, might fill in those blanks varies from place to place, and from fishery to
fishery.
On the East Coast, fishermen often blame the striped bass for
the decline of other species. Bass are
large fish that will, at some point, eat just about anything that they can fit
into their mouths, from lobster to tautog and from blue crabs to winter
flounder, so when any of those species slip into decline, there is always some
fishermen somewhere what are willing to stand up and say “The striped bass did
it!”
And, just about every time, that same bunch of fishermen
will then offer to do the public a favor by killing off more
of the supposedly over-abundant predators.
Maryland
watermen blamed striped bass for a drop in the blue crab population a few years
ago, and so fought against the harvest reductions recommended in the 2013
benchmark striped bass stock assessment. Their
claims of predation aren’t supported by the Maryland Department of Natural
Resources, which noted that
“There is no scientific data to support a supposition that Striped
Bass predation is causing a significant depletion of the Chesapeake Bay blue
crab population. In fact, studies
performed in Maryland and Virginia to assess the diets of striped bass indicated
that blue crabs make up a small percentage of the average striped bass diet.”
Despite such statement, many watermen don’t seem willing to take any responsibility
for the state of Maryland’s crab population. A group of them actually managed to get a state biologist fired when she refused
to accede to a regulation that, according to the then-Chair of Maryland’s Tidal
Fisheries Advisory Commission (who is also a crabber) said
“would harm the crab population, and would not bring watermen
any overall economic benefit.”
Now,
with the striped bass population overfished, it's harder to blame bass for other species' problems. In fact, it seems that the tables have turned, and there are now some
folks looking for a scapegoat for the striped bass' decline.
One group has decided that the current dearth of striped bass can be blamed on the seemingly inoffensive cownose ray.
“The science of sustainable seafood, explained.”
“We were founded by a group of fisheries scientists led by Dr.
Ray Hilborn. We are run by a small
staff, all of who [sic] have advanced degrees in some element of
fisheries. All of our posts, features,
and editorials are edited and fact checked by experts.”
That sounds like an impressive set of credentials.
Dr. Hilborn is a very well-known fisheries
scientist, who has authored texts used to train the next generation of marine
biologists. More
recently, he received substantial attention in the press for his role in a
detailed study suggesting that forage fish stocks, which form an important part
of the marine food web, were not put at risk by industrial-scale harvesting by
the so-called “reduction fleet,” which study was funded by a group called IFFO
(2012) Ltd., an
At any rate, with respect to striped bass, Sustainable
Fisheries starts by saying
“In February, a much-anticipated Atlantic striped bass stock
assessment was presented to the Atlantic striped bass stock assessment was
presented to the Atlantic States Marine Fisheries Commission (ASMFC). The preliminary results were incomplete due
to the government shutdown, but the outlook is bleak on a fishery well-known
for its recovery in the early 2000’s.
With numerous fishery news outlets reporting on this story, we wanted to
provide a historical perspective on the fishery and offer some considerations
for policy makers on how to more effectively manage this resource going
forward.”
Again, it sounds good. But after that first paragraph, things start
really heading downhill.
One of the most striking aspects of Sustainable Fisheries’
striped bass page is that the only time the terms “overfished” and “overfishing” is in reference to the 2016 stock assessment update, which found that neither
applied to the bass back then; Sustainable Fisheries never explicitly
states that, according to the benchmark 2018 assessment, the striped bass stock
is overfished and undergoing overfishing today.
Instead, it merely notes that
“Female spawning stock biomass…will fall below the target
threshold [sic] for the first time since 1995, if the preliminary
assessment holds true. The threshold is
91,436 metric tons, and the assessment estimates that the [spawning stock
biomass] fell to 68,476 in 2017.” [emphasis
added]”
Leaving aside the fact that there is no such thing as a “target
threshold”—the biomass target represents the stock’s optimum abundance level,
while the biomass threshold defines the point where the stock becomes
overfished—the website seems to make a determined effort to describe an
overfished striped bass stock without ever coming out and actually using that
term.
By using the phrase “if the
preliminary assessment holds true,” Sustainable Fisheries seems to be making an intentional effort to
cast doubt on the conclusions of the 2018 benchmark stock assessment, a theme
that carries forward in the next paragraph, where it notes that the outcome of
the 2018 assessment
“directly contradicts the ASMFC’s 2016 claim that ‘the 2016
Atlantic striped bass stock assessment indicates the resource is not overfished
nor experiencing overfishing…But piecing together various industry reports and
ongoing studies provides a more complicated picture, even before the most
recent assessment is released in a few months.”
To that end, it also perpetuates the message that striped
bass might be more abundant than the assessment suggests, but just staying farther offshore, saying
“the closure of the EEZ to all striped bass fishing effort
has meant minimal data collection outside the 3nm boundary. Again, fish don’t respect jurisdictional
boundaries, and if a nice pocket of warm water exists 4nm miles from shore,
striped bass will find it, while stock assessments may not.”
Again, the goal of such comments seems to be to impeach the
conclusions of the 2018 assessment.
But the real kicker comes at a different point in the
discussion.
The 2018 assessment clearly points to overfishing, combined with years
of below-average recruitment, for the striped bass’ current decline. And it’s
been recognized for more than a decade that weather during the spawn drives
recruitment success.
But Sustainable Fisheries suggests a different cause for below-average
recruitment: cownose rays.
“2012 yielded the lowest recruitment since the stock
rebuilt. Some blame the addition of invasive
species to key juvenile striped bass estuaries, namely those connected to
Chesapeake Bay…recent invasive species have been disturbing important food
webs. A likely culprit is the cownose
ray, which isn’t technically an invasive species, but has recently appeared in
record numbers in the Chesapeake Bay.
This ray has no natural predators in the Bay, and prefers a diet of bivalves
and crabs—precisely the foods juvenile striped bass need to survive.”
Except that juvenile striped bass don’t feed heavily on
crabs—although the eat them from time to time—and don’t really feed on bivalves. They certainly don't "need" crabs and bivalves "to survive." Even Sustainable Fisheries admits, elsewhere
on the same page, that
“Menhaden are a critical food source for striped bass, especially
juveniles in and around the Chesapeake Bay. [emphasis added]”
That statement is more in accord with the accepted science.
“During different stages in their life cycle, striped bass
feed on zooplankton, fish larvae, insects, worms, amphipods, Bay anchovy, spot,
menhaden, herring, shad, white perch, and yellow perch.”
Nowhere does NMFS suggest that bivalves and crabs are
critical to the juvenile striped bass’ diet.
And nowhere does it suggest that striped bass and cownose rays compete,
at any time, or at any place, for food.
It seems that Sustainable Fisheries may have a credibility
problem. Reading its "Atlantic striped bass" page, it appears that Sustainable Fisheries is more interested in sustaining the current level of striped bass landings rather than in sustaining the striped bass stock.
Although it claims to provide, and explain, the “science” of
sustainable seafood, what it is really providing, at least with respect to
striped bass, are excuses designed to mislead striped bass managers, and send
them down the wrong path.
But if managers allow themselves to be misled, and head down
the road that Sustainable Fisheries seems to be suggesting, we all will soon find,
to our sorrow, that the Atlantic striped bass fishery isn’t sustainable
any more.
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