Most striped bass anglers were surprised, and many were
openly skeptical, when a
stock assessment update released last October revealed that there was a 78.6%
probability that the striped bass spawning stock biomass would be rebuilt to
its target level by 2029 with no change to current regulations, provided
that fishing mortality did not rise above its 2021 level.
Even if the fishing mortality rate increased from 0.14, its 2021 level, to the target rate of 0.17, the rebuilding probability would still
be 52%, making rebuilding more likely than not. But if fishing mortality rose above that, and particularly if it
rose above the 0.21 threshold, which signals that overfishing has occurred, timely
rebuilding became increasingly unlikely.
Over all, the assessment update brought good news, first
because it found that rebuilding by 2029, without the need to impose draconian management
measures, was possible, and second because it made it clear that, if fishing
mortality could be constrained at or below the target level, such rebuilding was
likely.
However, as many anglers quickly noted, keeping fishing mortality
at or below target, particularly with the large 2015 year class now bracketed by
the 28- to 35-inch slot limit, might be very hard to do. Angler effort is typically driven by striped
bass abundance, and with the abundant 2015s being caught all along the striper
coast, effort-driven mortality is likely to increase.
At last month’s meeting of the Atlantic States Marine
Fisheries Commission’s Atlantic Striped Bass Management Board, Dr. Michael
Armstrong, the Massachusetts fishery manager, expressed concern that the
assessment update’s prediction—that the striped bass had a 78.6% chance of
being rebuilt by 2023—wasn’t realistic, because the fishing mortality rate
wouldn’t remain at 0.14. He noted that
recreational striped bass landings for the first eight months of 2022 were
substantially higher than landings in 2021.
He warned,
“I want the Board to be conscious…It doesn’t take a lot to
change the course of the recovery.”
Emerson Hasbrouck, the Governor’s Appointee from New York,
observed that
“We’re getting close to being on the razor’s edge here,”
and asked whether there would be another stock assessment update presented in 2023.
His question set
off a brief discussion, which resulted in Toni Kearns, the Interstate Fishery
Management Program Director for the ASMFC, stating that there weren’t
sufficient resources available to prepare such an update; the necessary persons
were “at or more than at” their full capacity, and in order to perform a new
striped bass assessment update, another scheduled assessment would have to be
delayed.
Having said that, Ms. Kearns noted that, while a lack of
additional capacity prevented the ASMFC from performing assessment update in
2023, it should be able to determine whether the volume of fish actually removed
from the striped bass stock in 2022 roughly equaled the removals predicted by
the population model. Mr. Hasbrouck expressed
support for such an approach.
Dr. Armstrong, however, was not completely convinced. He suggested that
“This is a billion dollar fishery. Maybe instead of a spot assessment, striped
bass is the one we should do.”
He then pointed out the biggest flaw in past striped bass
management efforts, that
“we never hit our target [fishing mortality rate], at least
for any amount of time.”
Facts support Dr. Armstrong’s concerns. Addendum
IV to Amendment 6 to the Atlantic Striped Bass Interstate Fishery Management
Plan, adopted in 2014, saw the fishing mortality rate drop below its
target level in 2015, but increase in subsequent years. Addendum
VI to Amendment 6 to the Atlantic Striped Bass Interstate Fishery Management
Plan, adopted in 2019, reduced
fishing mortality in 2020, but saw such mortality increase in the ocean, but
not in the Chesapeake Bay, in 2021.
Addendum VI’s management measures remain in effect, and permitted
a substantial increase in 2022 landings.
Not every Management Board member shared Dr. Armstrong’s
concern. Steven Train, the Governor’s
Appointee from Maine, advised that the Management Board should trust the
science behind the stock assessment’s projections, and asked rhetorically,
“How much damage can we do if we let this go for another
year?”
Tom
Fote, the Governor’s Appointee from New Jersey, is usually quick to question scientific
conclusions, and predict that they will prove to be wrong after a few years
have passed, but he broke that mold in last month’s discussion, saying
“I’ve been sitting around the table for a long time; we
always say that we have to trust the science…I’m satisfied…I agree with the
stock assessment.”
Which, in the end, wasn’t surprising, for in this case, "the
science" supported maintaining the current management measures; a new stock
assessment might call for additional restrictions, and Fote has always been
consistent in one regard—he supports whatever management action might allow New
Jersey anglers to kill more striped bass.
Dr. Armstrong responded to both comments, addressing Mr.
Train by saying,
“I don’t criticize science, but we have empirical evidence”
of sharply increased landings. Such comment was very much to the point,
as the assessment update, which found a 78.6% chance
of rebuilding the stock by 2029, was predicated on the fishing mortality rate
remaining at 0.14, not at the apparently higher level occurring in 2022.
Dr. Armstrong also reiterated his earlier statement:
“To Tom Fote’s point, we’ve failed time and time again
because we did not hit the target [fishing mortality rate].”
He seemed to have made his point, since the Management Board
and ASMFC staff agreed that the Atlantic Striped Bass Technical Committee
would, once the Marine Recreational Information Program estimates for
2022 were completed, compare actual removals with the model’s projections, and provide
a report at the May 2023 Board meeting.
If excess fishing mortality is revealed in May, work on
additional fishery management measures could begin.
What do they tell us so far?
First, striped bass fishing effort has increased
substantially. Anglers took slightly over
16,000,000 trips primarily targeting striped bass through the end of
October 2022, compared to just 12,800,00 trips during the same period of 2021.
Striped bass harvest showed a far sharper increase, going
from about 1,200,000 fish in the first 10 months of 2021 to more than 2,500,000
by October 31, 2022. In fact, the number
of striped bass harvested by anglers in the first 10 months of 2022 far exceeded
the 1,840,000 fish landed in all of 2021—and the last two months of 2022 saw very
substantial striped bass fishing activity in southern New England and the New York
Bight. It would not be surprising to see final 2022 landings approach or exceed 3 million fish.
But recreational striped bass fishing mortality is not all
about harvest; fish that die after release often comprise an even greater
number of removals. In that respect, the 2022 story is just a little different.
During the first 10 months of 2021, anglers released just
under 22,500,000 striped bass; for the same period in 2022, that number fell to
a little less than 19,750,000; using the currently accepted 9% release
mortality rate, that equates to a little over 2,025,000 additional removals
through October 31, 2021, and a little over 1,775,000 additional removals through
October 31, 2022.
Add release mortality to the harvest, and we end up with
roughly 3,225,000 striped bass removals for the first 10 months of 2021,
compared to 4,275,000 removals—nearly 1,000,000 more—for the first 10 months of
2022.
That’s substantial.
Harvest and release estimates for the last two months of
2022 won’t be available until February, so it will be a while before managers
know what overall 2022 fishing mortality will be. In addition, the fishing mortality figure
represents a rate of removals, so an increase in removals don’t
necessarily indicate a corresponding increase in fishing mortality; if the
spawning stock biomass is also increasing, as it is in the case with striped
bass, the change in the fishing mortality rate will also depend on the rate of
biomass increase.
Still, removals increased more than 30% between October 31,
2021 and the same time this year; the biomass clearly didn’t increase that much. Thus, it is virtually certain that the fishing
mortality rate for 2022 will be substantially greater than 0.14, and it is very,
very possible that it will also exceed the 0.17 target.
Will it also exceed the 0.21 threshold, and trip a
management trigger in the newly adopted Amendment
7 to the Interstate Fishery Management Plan for Atlantic Striped Bass?
Without the November/December data, I don’t want to predict
that right now. However, I will predict
that discussions at the May 2023 Management Board meeting will prove extremely interesting,
and might well determine the long-term health of the bass.
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