Fishermen concerned about the future of Atlantic striped bass now have more reason to worry: On October 15, the Maryland Department of Natural Resources released the results of its 2021 juvenile abundance survey, which reported a poor striped bass spawn for the third year in a row.
The juvenile abundance index (JAI) for 2021 is 3.2, compared to
a long-term average of 11.4. The JAIs for 2019 and 2020 were 3.4 and 2.5,
respectively.
Maryland’s juvenile striped
bass abundance survey measures the production of
young-of-the-year striped bass by sampling 22 established locations within the
Chesapeake Bay, and producing an index reflecting the number of
young-of-the-year bass caught in each sample. The survey, which has been
performed annually since 1954, provides the longest continuous set of striped
bass recruitment data available anywhere, and is probably the best single
indicator of future striped bass abundance.
The recent JAI values are troubling because the Atlantic States
Marine Fisheries Commission’s Atlantic Striped Bass Management Board
(Management Board) is obligated to rebuild the
striped bass stock by 2029, but it isn’t clear that they have the
building blocks—that is, enough younger striped bass—needed to do so. That was
acknowledged by Massachusetts fishery manager
Michael Armstrong at the May 2021 Management Board meeting when
he said, “we’ve got five-year classes locked and loaded, with nothing behind
2014 [sic]. We
have the 2015-year class, and 2014 was not bad out of the Hudson. That is all
we’ve got to rebuild with…We have to start doing draconian things to get this
stock back.”
Despite such need for action, the Management Board continues to
move forward slowly. It is considering measures to protect the 2015 year class,
but such measures will probably not be in place until 2023. In the meantime,
immature bass from the 2017 and 2018 year classes are being removed from the
stock in the Chesapeake Bay, while the population of fish from the 2014 and
2015 year classes is being whittled down all along the coast. Given the poor
2021 JAI, it is very possible that striped bass population in October 2021 is
already smaller than it was when Mr. Armstrong made his comments in May.
To understand the current threat facing the fishery, it’s
probably necessary to take a deeper look at striped bass recruitment.
The coastal migratory stock of striped bass spawns in the Hudson
River, Delaware River, Chesapeake Bay, and the Albemarle and Roanoke rivers of
North Carolina. However, as the 2019 striped bass stock
assessment reveals, “Tributaries of Chesapeake Bay, most notably the
Potomac River, and also the James, York, and most of the smaller rivers on the
eastern shore of Maryland, are collectively considered the major spawning
grounds of striped bass.” Thus, the Maryland JAI is a particularly important
bellwether for striped bass abundance; the Atlantic States Marine
Fisheries Commission’s Atlantic Striped Bass Plan Development Team has stated
that “the Maryland JAI is closely correlated to the coastwide
age-1 estimates from the stock assessment model.”
Since the turn of this century, four large year classes of
striped bass have been produced in the Chesapeake Bay: 2001
(JAI=50.75), 2003 (JAI=25.75), 2011 (JAI=34.58), and 2015 (JAI=24.20). Of those
four, the 2001s and 2003s, due to their age and years of harvest, now form a very small and
steadily declining segment of the population. And, although the 2011 JAI was
nearly 50% higher than the JAI for 2015, the number of 2015s that survived to age 1 was
significantly greater.
Thus, the 2015 year class must be the focus of any rebuilding
effort.
Over the past ten years, with the exception of 2015, striped
bass recruitment in the Chesapeake Bay has been disappointing. The decade began
with a 2012 JAI of 0.89, the lowest ever recorded in the history of the
Maryland survey. Recent recruitment has proven so poor that the JAI’s long-term
average has dropped from 11.9 in 2015 to
11.4 today.
Over the entire ten-year period between 2012 and 2021, the average
JAI was 8.12, which is substantially below the long-term average. What is more
troubling is that the average JAI for the past decade is well below the JAI
average of 10.85 for the decade between 1967 and 1976, which immediately
preceded the stock collapse of the late 1970s and early 1980s.
Fortunately, the patterns of the past do not dictate the striped
bass’ future. Whether the stock rebuilds, languishes near current levels, or
declines into collapse depends not on what happened a half-century ago, but on
what happens over the next few years, both in the spawning rivers and at
meetings of the Management Board.
Striped bass recruitment is heavily dependent upon environmental
conditions in the spawning rivers. When a cold winter is followed by a wet spring,
and spawning bass experience cool water temperatures and high freshwater flows,
recruitment is usually high; warm winters followed by dry springs lead to
unsuccessful spawns. During the late 1970s and early 1980s, spawning conditions
were uniformly poor; between 1975 and 1988, the JAI never rose above 8.45 in
any year, and averaged just 4.35.
Recent environmental conditions in the Maryland spawning rivers
have also been unfavorable for striped bass recruitment, and no one can predict
when favorable conditions will next occur. When the striped bass stock began
its collapse fifty years ago, conditions remained unfavorable for nearly two
decades; after a large year class (JAI=30.52) emerged in 1970, it took 19 years
before another large year class (JAI=25.20) was produced in 1989.
Yet, while the weather remains beyond human control, it is
Management Board action—or inaction—that will determine whether the striped
bass spawning stock is given the protections it needs to endure until favorable
spawning conditions recur, or whether it will be allowed to dwindle and perhaps
collapse in the face of an extended period of low recruitment.
Prior to, and even during, the stock collapse of the 1970s and
early 1980s, the striped bass fishery was effectively unregulated. No single
entity had the authority to implement coastwide management measures, and the
individual states seemed more concerned with maintaining a level playing field
for their own fishermen than they were in rebuilding the overfished stock.
There were no commercial quotas, and few states imposed bag
limits on anglers. The size limit, typically 16 inches fork length on the
coast, and smaller in the Chesapeake Bay, was dictated by market demand rather
than by science. Although a very few “gamefish states” prohibited the sale of
striped bass, in most places, there was no significant distinction between
commercial and recreational fishermen; fish could be sold by anyone, with no
commercial license required. Under such circumstances, few anglers released their
striped bass; fish that they didn’t intend to eat themselves were sold to local
restaurants and markets.
Today, the striped bass fishery is regulated by the Management
Board which, in 1984, was empowered by Congress to develop effective
coastwide management measures that must be adopted by all of the states between
North Carolina and Maine. The problem is no longer a lack of coastwide
regulation, but a Management Board that functions reasonably well while the
stock remains healthy, but has proven reluctant to act proactively in order to
avert a crisis and instead waits for a crisis to occur before taking action.
Such crisis has now arrived.
The striped bass stock is already overfished, and appears to be
entering a period of low recruitment. Four of the last six years have seen JAIs
that were lower than the average JAI for the years when the stock had
collapsed, and it is impossible to predict when, or even if, things will turn
around.
It is possible that the Chesapeake Bay will produce a big year
class in 2022; however, given that North America is heading into another La Niña cycle,
which is expected to usher in another warmer-than-usual winter into the
Mid-Atlantic region, it is far more likely that the 2022 JAI will again reflect
poor spawning success.
Thus, the fate of the striped bass is in the Management Board’s hands.
It can take a precautionary stance, assume continuing low recruitment, and
adopt measures to substantially reduce fishing mortality and conserve the
spawning stock until environmental conditions improve. Or, it can continue on
its current path, assume that recruitment will return to more typical levels
and, by doing nothing, risk driving the stock into a second collapse.
Whatever it chooses to do, the decision, and any resulting credit or blame,
sits squarely on the Management Board’s shoulders. Stakeholders can only hope
that it proves up to its task.
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NOTE: This
essay first appeared in “From the Waterfront,” the blog of the Marine Fish
Conservation Network, on October 18, 2021.
“From the Waterfront” can be found at http://conservefish.org/blog/
Since it appeared there, the ASMFC’s Atlantic Striped Bass
Management Board met on October 20, and directed the Atlantic Striped Bass Plan
Development team to develop a formal rebuilding plan that will restore the
spawning stock biomass to its target level no later than 2019, and to
incorporate low recruitment scenarios into such plan. While it is not certain how the Management
Board will receive such plan when it is presented to them at their next
meeting, which is scheduled to occur in January 2023, at this moment, it
appears that the Management Board has taken an important step toward addressing
both the overfished status of the stock and the current below average
recruitment. Hopefully, the Management
Board will follow up on its initial action, and take meaningful action to fully
restore the striped bass population.
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