Up in Canada, some say, they have a problem.
There
are just too many striped bass. As a
result, the Atlantic salmon population is crashing.
At least that’s what Atlantic salmon anglers claim.
The Canadian Maritimes host separate, geneticallyidentifiable striped bass stocks. The
largest spawns in the Miramichi estuary, which is located in the Province of
New Brunswick. The Miramachi has,
historically, also hosted a strong run of Atlantic salmon, which has declined
substantially in recent years. Salmon
anglers blame a resurgent striped bass population for the salmon’s ills.
The salmon fishermen argue that the bass are eating most of
the smolts—the young, recently-hatched salmon that have grown large enough to
leave the rivers and head out to sea, where they will spend most of their
lives. They claim that a 20-year study,
which found that between 55 and 75 percent of the smolts made it out of the
rivers and into the open Atlantic in the early 2000s, but less than five
percent did so in 2022 and 2023, demonstrates that the bass are killing off the
Atlantic salmon population.
For, in the same Canadian waters, striped bass have staged what,
to striped bass fishermen, at least, has been a magnificent recovery.
In the late 1990s, the Canadian Department of Fisheries and
Oceans believed that the entire female striped bass spawning stock biomass was
composed of fewer than 5,000 individuals, and closed the commercial and
recreational fisheries as a result.
Perhaps in response to that action, female spawning stock biomass
quickly increased, and was estimated at about 900,000 fish in 2019.
The increasing striped bass population led the Department to
reopen the recreational fishery in 2013, and to allow some commercial fishing,
first by indigenous Tribes, and later by others. Last year, it increased the Tribal quota from
50,000 to 175,000 bass and also increased the recreational bag limit from three
fish to four (there is also a slot size limit of 50 to 65 centimeters, or roughly,
19.7 to 25.6 inches). Earlier this year,
the Department ordered the 43 commercial gaspereau (the regional name for the
alewife, Alosa pseudoharengus) fishermen in the region to retain the
first 500 striped bass measuring between 50 and 65 centimeters that they
incidentally capture this season.
A 2024 stock assessment update suggests that the reopened
fisheries may have had a significant impact on the female spawning stock, which
had declined to an estimated 334,900 individuals.
That reduction was not enough to satisfy the Atlantic Salmon
Federation, an organization of recreational fishermen that argues for salmon
conservation, and insists that Canada reduce the female striped bass spawning
stock to just 100,000 fish.
But, despite the one study that the salmon advocates quote,
the science doesn’t necessarily support the claims of out-of-control striped
bass predation on salmon smolts.
A survey of striped bass stomach contents, conducted in
2022 by the Department of Fisheries and Oceans, found that 68 percent of the bass sampled had nothing in their stomachs
at all, suggesting that they didn’t feed heavily when they congregated in the Miramichi
estuary to spawn. Of the bass that did
have something in their stomachs, alewives—gaspereau—and some smelt dominated. Although some salmon smolt were present, they
made up a very small proportion of all stomach contents.
“It is not clear from the available studies that reducing
striped bass spawner abundance to a level of the mid-2000s, i.e. 100,000 spawners
or less (as requested by [the Atlantic Salmon Federation]), would improve the
acoustic tagged smolt survival estimates or the population level relative
survival rates derived from the cohort model, nor landings of gasereau [sic]
and rainbow smelt in the commercial fisheries.”
But the Atlantic salmon anglers were not to be deterred. When
the Department of Fisheries and Oceans declined to cull the bass population
back to just 100,000 spawning-age females, they formed an organization, Save Miramichi
Salmon Inc., which sued the Department, seeking to compel it to reduce the
striped bass population.
A spokesman for the organization alleged that
“DFO mismanagement and bad science over several years are
destroying a National and Provincial treasure—the Miramichi Atlantic Salmon—and
immediate remedial action is required now.”
For example, when describing the Atlantic salmon, it alleges
that
“Atlantic salmon (salmo [sic] salar), referred
to as the ‘King of Fish’, are a species of salmon native to waters throughout
the North Atlantic Ocean. Atlantic
salmon is endemic to the Miramichi River system.
“Atlantic salmon have frequented the Miramichi River since
the end of the last ice age and are of significant cultural and economic importance
to Canadians, including, but not limited to, Indigenous Canadians and
non-indigenous communities on the Miramichi since European settlement… [numbering omitted]”
But when describing the striped bass, the allegations are
far less fulsome, stating only that
“Atlantic striped bass (Morone saxatilis) are a species of
rockfish which live throughout the Atlantic coast of North America, including
the Gulf of St. Lawrence.
“Striped bass are commercially and recreationally significant
fish, and, historically, were subject to significant commercial harvest. [numbering omitted]”
No mention of bass being endemic to the Miramichi estuary, and
no mention of their long presence and well-established role in the estuary’s
ecosystem. And no mention that Atlantic
salmon, too, were “historically…subject to significant commercial harvest.”
The Claim’s language strives to make it clear to the court
that while Atlantic salmon are the “King of Fish,” striped bass are nothing but
an upstart commoner, and more, a commoner that is committing acts of treason
against the crown.
The Claim makes allegations like
“Because of geographical separation and historic numbers, and
standing net and sport fisheries, striped bass did not, historically, have a
significant impact on the number of Atlantic salmon smolts migrating to the
ocean, feeding only on a limited number of smolts during the annual migration,
primarily from the Northwest and Little Southwest Miramichi systems.
“In the 1980s, populations of striped bass in the Miramichi
River were considered stable and healthy despite being significantly lower than
they are today. [numbering omitted]”
The problem is that the phrase "historic numbers" is vague enough to mean whatever the plaintiff might
want it to mean. It’s a particularly
amorphous concept when it comes to natural resources such as salmon and bass,
when “historic” conditions, due to intentional and unintentional human
manipulation of the environment, may be very different from what the default—the
pre-human or, in a North American context, the pre-European—conditions of the
resources might have been.
In that regard, it’s not the “historic,” but instead the prehistoric,
conditions that should be used as a benchmark.
Applying that benchmark to the Miramichi’s salmon and striped bass, it’s impossible to note that both lived in apparent harmony for many centuries—for millennia—without bass driving down the Atlantic salmon population.
For thousands of years
before there were significant net fisheries—other than those of the Tribes, once
they arrived—and before there were any recreational fisheries at all, Atlantic
salmon and striped bass both utilized the Miramichi estuary and, given by the
numbers of fish the first explorers found, somehow managed to thrive.
Maybe it was because the bass and the salmon were geographically separated, as the plaintiffs contend, although that seems unlikely, as healthy populations tend to expand into all suitable space.
The fact is that we have no idea what the spatial distribution of either
species was when Jacques
Cartier first explored what is now the Gulf of St. Lawrence in 1534. Any allegation that the species were
spatially separated at that time is the merest speculation, without supporting
facts; it is far more likely that any separation that occurred happened later
on, after human influence drove down the region’s salmon and striped bass populations.
In any event, the 1980s hardly define either “historical”
times or a healthy striped bass population, and to try to define ecological
relationships on the basis of what has occurred in the past 50 years, or even
the last century, is a fool’s errand.
But where things really get interesting is in the Claim section,
“Atlantic Salmon—Decline and Cause”, which alleges
“In or around 2010, Atlantic salmon returns to the Miramichi
River began to decline rapidly. Between
2010 and 2024, the river’s salmon population declined by approximately 96%.
“The decline in Atlantic salmon in the Miramichi River
corresponds to the rapid growth of striped bass, a known predator of juvenile
salmon, in the same areas.
“In 2019, the Standing Committee on Fisheries and Oceans
[which is composed of politicians serving in Canada’s Parliament, and not
of fisheries scientists] issued a report identifying the rapid increase in the Gulf
of St. Lawrence striped bass population as placing strain on struggling
Atlantic salmon populations. The
Parliamentary committee recommended [the Department of Fisheries and Oceans]
implement management measures that prioritize the long-term balance of fish
species in the Miramichi River, including establishing upper and lower limit
reference point thresholds which should be adjusted according to justifiable
scientific evidence. [numbering omitted]”
Apparently, the recreational fishing interests bringing the
lawsuit are trying to blame the striped bass for the Atlantic salmon’s woes.
But the salmon’s problems, across the entire North Atlantic
basin, run deeper than that.
“Adult returns to many Atlantic salmon wild and hatchery
stocks of the North Atlantic have declined or collapsed since 1985. Enhancement, commercial fishery closures, and
angling restrictions have failed to halt the decline…The decline and collapse
of stocks has common characteristics: 1)
cyclic annual adult returns cease, 2) annual adult returns flatline, 3) adult
mean size declines, and 4) stock collapses occurred earliest among watersheds distant
from the North Atlantic Sub-polar Gyre (NASpG).
Cyclic annual adult returns were common to all stocks in the past that
were not impacted by anthropogenic changes to their natal streams. A flatline of adult abundance and reduction
in adult mean size are common characteristics of many overexploited fish stocks
and suggest illegal, unreported, and unregulated (IUU) fisheries exploitation
at sea. Distance from the NASpG causing
higher mortality of migrating post-smolts would increase the potential for
collapse of these stocks from IUU exploitation…Distribution in time and space
of former, legal high-sea fisheries indicated fishers were well-acquainted with
the ocean migratory pattern of salmon and combined with a lack of surveillance
since 1985 outside Exclusive Economic Zones or in remote northern regions may
mean high at-sea mortality occurs because of IUU fisheries. The problem of IUU ocean fisheries is acute,
has collapsed numerous stocks of desired species worldwide, and is probably
linked to the decline and impending collapse of the North Atlantic salmon
population.”
Whether or not that conclusion is correct, the paper reminds
us that the
decline in salmon populations isn’t limited to the Miramichi River, and is
occurring even in places where there are no striped bass. A United Kingdom-based conservation group,
the Missing Salmon Alliance, notes that
“Wild Atlantic salmon have declined by around 70% across the
North Atlantic over the last few decades.
In Great Britain the species was listed as endangered by the
International Union for the Conservation of Nature (IUCN) in December 2023,
with British salmon having suffered an additional 30-50% decline since 2006 and
a projected 50-80% decline between 2010 and 2025.”
The Alliance suggests that changes in the marine environment,
which have caused a decline in the zooplankton, have also created food chain
issues for juvenile salmon.
“Like elsewhere in the world, Canadian stocks have been in rapid
decline for the past 40 years…Human interference, industrial aquaculture
included, is the considered the [sic] largest threat to Canadian stocks…
”…While the historic decline of salmon stocks is largely due
to low survival rates at sea, there are always larger declines where fish
farming is close to wild salmon…”
And
climate change also plays a role. Canada’s
Department of Fisheries and Oceans notes that
“Rising water temperatures, lower water levels, and more frequent extreme weather events are all contributing to the decline of salmon populations.”
“With warmer summers, the water temperatures are beginning to
stray away from the Salmon’s optimal temperature (4-12o C),
approaching the upper threshold temperatures in which they can survive (28o
C being lethal, and anything over 20o C impeding survival). Over the summer of 2017, the Miramichi River
contained periods where water temperature readings exceeded 30o C!”
The Department of Fisheries and Oceans went on to advise
that
“in the Miramichi River, the annual abundance of the past
decade have frequently been at record lows, particularly for the earlier
maturing one-sea-winter salmon. Salmon
populations in the southern regions are impacted by rapidly changing marine,
estuarine and freshwater environments, and by anthropogenic stressors,
including land-use and the spread of invasive species.”
So it’s clear that there are many factors causing the
decline of the Miramichi’s salmon.
Striped bass do not bear the sole responsibility.
Still, it would be wrong to completely discount striped bass
predation. When any fish is
at a very low level of abundance, any removals, regardless of
cause, will have an adverse effect on the stock. As
the Department of Fisheries and Oceans observed,
“Migrating smolts face predation from species such as striped
bass and cormorants, while adult salmon may be preyed on by seals or other
larger predators. Though natural,
predation can exacerbate challenges associated to human activities, climate or
ecosystem shifts for Atlantic salmon throughout its range.”
In other words, striped bass predation didn’t cause the
Atlantic salmon runs to collapse, but they may be making it more difficult for
such runs to be restored.
“Impacts on Atlantic salmon due to predation are more likely
to be a result of cumulative effects by a variety of species along with other
anthropogenic factors rather than any one individual component. [One team of researchers] state that predation
is a natural phenomenon and one that does not necessarily imply that it is a
particular driver of the current population declines of salmon. [Another team of researchers] have similarly
noted that predation impacts on Atlantic salmon are not likely to be the
primary cause for population declines in the North Atlantic but as
others have noted predation may act to keep depressed populations from
recovering. [citations omitted, emphasis
added]”
“Control or removal of predators may have similar
counterproductive effects. Predators
often select slow, weak, or sick prey such that predation is compensatory and,
in some cases, may allow disease to spread, in instances where predation of
diseased animals is more frequent.”
So, taking all of the above into account, it’s clear that the
striped bass is not responsible for all of the ills besetting the Miramichi’s
Atlantic salmon runs. But the bigger
point of this post is to examine, in detail, why the striped bass ought not to
be blamed for the ills besetting any other marine resource, even though the
bass might eat a few fish every once and again.
Yet that’s a theme that we hear again and again.
For many years, New York’s striped bass anglers were
dismayed to hear one of the state’s representatives on the Atlantic States Marine
Fisheries Commission’s Atlantic Striped Bass Management Board repeatedly
suggest that striped bass were too abundant, and were driving down the
populations of other managed species, saying things like
“is
this an attempt by the state to maybe address the concern that the stock of
striped bass in Chesapeake Bay is growing much greater than anticipated and is
having an additional negative effect on menhaden?..
And
“The
bottom line is that they’re opportunists, whatever is there they’re going to eat,
so to speak…
His answer, of course, to purported declines in the menhaden
and winter flounder populations was the same one that the Atlantic salmon
anglers have to declines in their favorite fish: There are too many striped bass. They’re eating them all.
And far too many other folks also feel that way.
“there could be a trophic collapse if the striped bass abundance
increases…
“…if you have record young of the year, you’re going to have
record competition for the same food resources…we’ve got an amazing abundance in
the Chesapeake Bay of channel bass, puppy drum, red fish.
“They are in the same trophic level, they’re eating the same
things, they’re eating the same thing all the way up into freshwater and all
the way down to the ocean…”
Clearly, there are too many striped bass.
Because, at the same meeting, Russel Dize, Maryland’s Legislative
Proxy, complained
“I’ve been a commercial fisherman for 55 years in
Maryland. I’ve watched the striped bass
come and go. At this time, we’ve
probably got more striped bass in the bay than I have ever seen in my
life. We’ve got so many striped bass
that it’s affected our crab-catching industry.
We are probably down to a low ebb last summer on crabs.
“One of the predators is rockfish, striped bass. When the charterboats catch the striped bass
and they clean them, you can count anywhere from ten to forty striped bass in
the belly of a rockfish.”
Too many striped
bass once again.
It’s not overharvest by Maryland’s watermen that’s the
problem with the Bay’s blue crab population.
It’s not hypoxia, or the loss of seagrass, or any other possible cause
that caused the Bay’s crab population to drop.
It’s too many striped bass.
It’s always too many striped bass.
From Maryland to the Miramichi, too many striped bass are
the cause of all our fisheries problems, starting out with Atlantic salmon and
ending up with winter flounder.
They do so much harm that you have to wonder how any fish
survived in those thousands of years between the retreat of the Wisconsin Glacier
and the arrival of the first European settlers, who came to North American
shores and, finally, put out their nets in the spawning rivers and began to save the the continent's marine resources from the ravages of the
striped bass.
Or, perhaps, you have to wonder whether some of these folks
are getting things backwards, and that the fish didn’t need the Europeans to
save them from the striped bass, but rather that the fish needed someone
to save them from the rapidly multiplying Europeans and their generations of
progeny, who merely find it convenient to blame the striped bass from the
consequences of their own actions.
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