On October 19, the Maryland Department of Natural Resources released
the results of its 2026 juvenile striped bass abundance survey. The 2026
survey recorded a juvenile abundance index value (JAI) of 5.5, the highest
since 2018, but still barely half the long-term average of 10.8.
Maryland’s juvenile
abundance survey data provides a time series dating back to 1957; no other
juvenile abundance survey dates back as far. Each year, Maryland biologists
sample a total of 22 sites located in the upper Chesapeake Bay, and in the
Choptank, Potomac, and Nanticoke Rivers, with each spot sampled on three
separate occasions during the late spring and summer. Samples are taken with a
100-foot seine, and only striped bass less than three inches in length are
counted.
In 2026, the Maryland survey
captured 723 juvenile striped bass. Although it found striped bass to be
more widely distributed in 2026 than they were in immediately preceding years,
the highest concentrations of juvenile bass were found in the upper bay and in
the Choptank River, with lesser concentrations found elsewhere. A strong
striped bass year class would typically see high concentrations of juveniles
throughout the bay.
The average annual JAI for the eight-year period that began
in 2019 is 3.15, the lowest ever recorded in the 70-year
history of the survey. The next-lowest average for a comparable period,
3.57, was recorded during the years 1979-1986, a period defined by the
collapse of the striped bass stock. The record-low 2019-2026 average is bad
news for both the striped bass and for striped bass fishermen, whether
recreational or commercial, for as Allison
Colden, Maryland executive director of the Chesapeake Bay Foundation has
observed, “What happens in the Chesapeake Bay is a prediction for striped
bass’ future up and down the Atlantic Coast. Roughly 80 percent of the
coastwide striped bass population spawn here in the Bay.”
Two-thirds of the juvenile striped bass produced in the
Chesapeake Bay come
from Maryland waters. The rest are produced in the Virginia portion of the
bay, which also saw an improved juvenile abundance index in 2026.
While Virginia’s
2026 JAI, at 9.52, is being slightly above the state’s long-term average of
7.77, it’s important to note that the calculation of the long-term average
includes the period from the mid-1960s through 1986, when recruitment was
generally dismal. The Atlantic States Marine Fisheries Commission (ASMFC),
trying to avoid the distortions caused by those early years, uses the years
1992 through 2006 to gauge recruitment success. Should the JAI in any of the
four major spawning areas (Hudson River, New York; Delaware River, New Jersey;
Chesapeake Bay, Maryland; and Chesapeake Bay, Virginia) fall below the
25th percentile of all year classes produced in a spawning area during that
period, which in Virginia’s case is 8.22, for three consecutive years
(recruitment trigger), the ASMFC’s Atlantic Striped Bass Management Board
(Management Board) is
required to take remedial action.
2026 marks the
first time since 2020 that the Virginia juvenile abundance index did not
fall below 8.22.
The 2026 year class, made up of bass spawned in the Maryland
and Virginia portions of the Chesapeake Bay, as well as in the Delaware and
Hudson Rivers, will be the last year class produced prior to the completion of
the 2027 benchmark assessment of the striped bass stock. However, because the
2027 benchmark assessment will
only include data through 2025, the 2026 year class will not be considered.
However, that doesn’t mean that the 2026 year class won’t
have any near-term impact on the management process. Already, we’re seeing some
people try to spin the Maryland JAI as some sort of victory, with one
Connecticut charter boat captain, commenting on someone else’s Facebook post, announcing
that “5.5 is excellent!!!”>, perhaps out of hopes that managers will not
adopt more restrictive fishing regulations for the 2027 season.
Those hopes will probably be fulfilled, as it is highly
unlikely that the Management Board will consider any changes to striped bass
regulations before the 2027 benchmark assessment is released. The big question
is what will happen after that release occurs.
The Management Board’s
obligation to rebuild the spawning stock biomass to its target level by
2029 remains. But even if they accomplish that task, the poor year classes
produced over the past eight years are likely to lead to another population
decline. Recreational fishermen on the coast will begin to feel that decline in
2027, when the last successful year class, spawned
in 2018, grows out of the 28- to 31-inch slot size limit, and few
bass from the 2019 and 2020 year classes will be available to take their
place.
Although individual striped bass grow at somewhat different
rates, as a general rule, it takes seven years for a given year class to grow
into the slot limit, although a small proportion of each year class will enter
the slot as six-year-olds, and roughly half of the eight-year-olds remain under
the slot’s 31-inch maximum size. So, assuming that the size limit remains
unchanged, even if the striped bass manage to produce a strong year class in
2027, something that is not at all guaranteed, coastal anglers would have to
wait until 3034 before those fish were widely available for harvest.
In fact, it’s impossible to predict when the next strong
year class will be produced. The Maryland Department of Natural Resource has
noted that
Multiple factors affect striped bass spawning in the
Chesapeake Bay. Cold winters and wet springs tend to be beneficial for
spawning, and while Maryland experienced a cold winter, the prolonged regional
drought and resulting low river flows may have led to unfavorable conditions
for striped bass eggs and larvae. High river flows increase spawning habitat,
allow eggs to remain suspended in the water column, and bring larvae closer to
food sources. Other variables, including a shortened spawning period, could
also influence spawning success.
It’s difficult to predict when favorable spawning conditions
will return, although long-range
weather forecasts for the Maryland region for the three-month period
beginning on December 1, 2026 and running through February 28, 2027 predict a
mixed bag of conditions. Above-normal precipitation is expected, which should
end drought conditions and benefit the juvenile striped bass, but at the same
time, temperatures are also expected to be above normal, which could cause
water temperatures to rise too high, too soon and impair juvenile survival.
At least one Maryland biologist, Carrie Kennedy, who serves
as the director of the Maryland Department of Natural Resources’ Tidal and
Coastal Monitoring and Assessment Division, has suggested that favorable
conditions for producing a strong striped bass year class might never return.
In
response to the below-average 2026 JAI, she said, “The important piece of
information is that it is still below average, and it is now the eighth year of
low abundance.” She raised the possibility that the current poor spawning
conditions, and the current low JAIs, may constitute “the new normal,” and
opined, “Maybe we need to have a conversation about new reference points and
new expectations. I don’t think that we should expect the population to be
where it was in the early 2000s. We have a different Chesapeake Bay. We have a
different planet than we had in the early 2000s.”
But she may be giving up on striped bass too soon. The last
time the striped bass stock collapsed, spawning
success began to decline in 1975, and it took until 1989 before another
strong year class was produced. Measured against that 14-year span, the current
eight years of below-average JAIs does not seem quite as dire.
That would be particularly true if similar environmental
conditions contributed to both the last stock collapse and the current decline
in the Maryland JAI. A paper, “Perspective
comes with time: What do long-term egg and juvenile indices say about
Chesapeake Bay Striped Bass productivity?,” authored by James Uphoff and
published in the October 20, 2023 edition of the journal Marine and Coastal
Fisheries, suggests that may have been the case.
After comparing the bay-wide abundance and distribution of
striped bass eggs appearing in plankton net tows with the JAI time series, the
author came to the conclusion that
The shift to lower [JAIs] in the early 1970s was followed by
a strong decline in baywide [egg abundance] a decade later. The hypothesis that
the collapse [of the striped bass stock] was initially driven by recruitment
overfishing was not supported by trends in [egg abundance and distribution],
but low [egg abundance and distribution] during 1982-1988 indicated that
overfishing contributed to poor recruitment later. Poor habitat conditions
leading into overfishing explained the decline of Chesapeake Bay Striped Bass
in the 1970s and 1980s based on [egg abundance and distribution] and [JAIs].
Recovery, based on higher [egg production and broader egg distribution] was
accompanied by and complemented by the recovery of egg-larval survival…in the
early 1990s.
Based on that conclusion, it would seem premature to declare
that the past eight years’ poor JAIs represent “the new normal,” and that such
JAIs justify a revision of the reference points used to gauge the health of the
striped bass stock.
Instead, the research would seem to suggest that the best
course forward would be to do just what the ASMFC did in 1985: Impose very
conservative management measures designed to maintain the spawning stock
biomass at the highest practicable level, so that when favorable spawning
conditions return, the stock will have sufficient spawning potential to take
full advantage of the opportunity.
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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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