IS ANY FISH THAT DIES OF OLD AGE REALLY WASTED?

The philosophy behind salt water fishery management has changed over the years.

One hundred and fifty years ago, people questioned whether such management was needed at all.  Professor Thomas Huxley provided the opening remarks for the 1882 London Fisheries Exhibition, when he stated, in part, that

“A salmon fishery then (and the same reasoning applies to all river fisheries) can be exhausted by man because man is, under ordinary circumstances, one of the chief agents of destruction; and, for the same reason, its exhaustion can usually be prevented, because man’s operations can be controlled and reduced to any extent that may be desired by force of law.

“And now to the question, Does the same reasoning apply to the sea fisheries?  Are there any sea fisheries which are exhaustible, and, if so, are the circumstances of the case such that they can be efficiently protected?  I believe that it may be affirmed with confidence that, in relation to our present modes of fishing, a number of the most important sea fisheries, such as the cod fishery, the herring fishery, and the mackerel fishery, are inexhaustible.  And I base this conviction on two grounds, first, that the multitude of these fishes is so inconceivably great the number that we catch is relatively insignificant; and, secondly, that the magnitude of the destructive agencies at work upon them is so prodigious, that the destruction effected by the fisherman cannot sensibly increase the death-rate.”

Professor Huxley’s opinions were demonstrably false. Today, on the western side of the Atlantic, stocks of Gulf of Maine cod, Georges Bank cod, Atlantic herring, and Atlantic mackerel are all overfished, and are subject to restrictive rebuilding plans, although in the case of the cod, rebuilding efforts are showing no signs of success; mackerel, too, have proven resistant to rebuilding, with a follow-on rebuilding plan put into place after the initial plan failed to achieve its goals.

To be fair to the late professor, he did say that such fisheries were inexhaustible “in relation to our present modes of fishing,” and in 1882, those modes were still fairly crude.

The fishermen who drove stocks of cod, herring, and mackerel down to their current levels primarily fish with otter trawls—large, efficient nets made out of tough, synthetic twine.  When Professor Huxley spoke in 1882, such trawls had not yet been invented, nor had the steel-hulled, steam-powered trawlers that tow them yet come to dominate the fishing fleet.  Synthetic nets would not be imagined, much less widely used, until the middle of the following century; until then, nets were made out of cotton, making them susceptible to rot and much more visible to the fish.

So from the perspective of someone speaking in 1882, marine fishery management might have appeared unnecessary.  But the arrival of new, more efficient gear on the fishing grounds immediately began to impact fish stocks.  In the North Sea, the fishing mortality rate for plaice, a type of flatfish, doubled in the early 1900s; in 1937, an international agreement established a minimum size for the species, as well as a minimum mesh size for nets used in the fishery.

Thus, the need for some sort of fishery management measures was recognized.

However, there was still no general agreement on how such measures should be established, or precisely what such measures should achieve.  In 1918, Russian marine engineer Fedor Ilyich Baranov published “On the question of the biological basis of fisheries,” a paper which set the stage for modern fishery management, and the concept of maximum sustainable yield.

However, just how maximum sustainable yield, defined as

“the highest average catch that can be continuously taken from an exploited population under average environmental conditions,:

ought to be calculated was still up for debate.

In the mid-20^th Century, fishery managers concentrated on harvesting every possible fish that they could without collapsing the stock.  Some prominent scientists of the time scorned doing anything less.  Kevin M. Bailey, in his book Billion-Dollar Fish, wrote that

“One of the principal designers of US fishing policy was Wilbert Chapman.  He was the director of the School of Fisheries at the University of Washington, and in 1948 became the Undersecretary of State for Fisheries in the Department of State.  Later he worked closely with the tuna fishing industry as an advisor.  Chapman pushed the concept of maximum sustainable yield (MSY) as a policy rather than a scientific approach.  He said, ‘Less fishing is wasteful, for the surplus of fish dies from natural causes without benefit to mankind.’”

Since Dr. Chapman made that comment, most managers’ views have changed.  The Magnuson-Stevens Fishery Conservation and Management Act, which governs all fishing in federal waters, directs that federal fishery management plans shouldn’t necessarily achieve maximum sustainably yield, but instead must achieve “optimum yield,” which is defined as

“the amount of fish which will provide the greatest overall benefit to the Nation, particularly with respect to food production and recreational opportunities, and taking into account the protection of marine ecosystems; is prescribed as such on the basis of maximum sustainable yield from the fishery, as reduced by any relevant economic, social, or ecological factor; and in the case of an overfished fishery, provides for rebuilding to a level consistent with producing the maximum sustainable yield from such fishery.  [internal formatting omitted]”

Such definition recognizes that there may be economic and social benefits to killing fewer fish than fishing at maximum sustainable yield would allow, a concept particularly relevant to fisheries dominated by anglers, rather than commercial fishermen.  It also opens the door to managing fish in a way that allows them to fulfill their historical role in the ecosystem, a consideration particularly relevant in the case of forage fish—those species which fill a particularly large place in the food web, as food for not only other fish, but for aquatic birds, marine mammals, etc.—where high but sustainable harvests of such species might deprive other animals of their customary prey.

Unfortunately, we still see occasions where fishery managers seem to cling to Dr. Chapman’s outdated philosophy, and adopt management measures intended to harvest every possible fish, even when such high levels of management might not accurately represent optimum yield.

The best example of that might be the Mid-Atlantic Fishery Management Council’s Bluefish Fishery Management Plan.

The bluefish fishery is predominantly recreational.  When Amendment 1 to the Bluefish Fishery Management Plan was adopted in 2000, it allocated 83% of bluefish landings to the recreational sector and 17% to commercial fishermen, based on historical landings.  However, it also included a provision that authorized the transfer of supposedly unused recreational quota to the commercial fishery.

Such reallocation might seem logical on its face.  However, the recreational bluefish fishery is predominantly a catch-and-release fishery, with about two-thirds of all bluefish caught returned to the water each year.  And in such a recreational fishery, the greatest economic and social benefits aren’t derived from yield, but from maintaining a high abundance of fish, that makes it more likely that anglers will encounter them when they go fishing, and thus encourage people to fish and to fish more often.

Thus, the unharvested recreational quota isn’t truly unused, and transferring unfilled recreational quota to the relatively low-value commercial bluefish fishery does not necessarily meet the injunction to manage for optimum yield.

Nonetheless, when a new Bluefish Allocation and Rebuilding Amendment was adopted in 2021, such amendment maintained the quota transfer provision.

There are other, practical reasons not to kill every available fish.

One of my undergraduate degrees is in History, where I concentrated on modern East-Central Europe.  When you study that region and time, when revolutions occurred on a regular basis, it doesn’t take long before you come across the axiom that

“Revolutions aren’t caused by continued poor conditions, but by dashed expectations.”

 In a fisheries context, that translates to

“It’s always easier to give people more fish than to cut back on their landings,”

and certainly has real-world application.

Consider the scup fishery.

Scup produced a very large year class in 2015, causing biomass to soar well above the biomass target.  So in December 2017, at a combined meeting of the Mid-Atlantic Council and the Atlantic States Marine Fisheries Commission’s Summer Flounder, Scup, and Black Sea Bass Management Board, fishery managers decided to allow states—including the northeastern states of New York, Connecticut, Rhode Island, and Massachusetts, which account for over 95% of annual recreational scup catch—to increase their bag limit from 40 to 50 fish for anglers fishing from for-hire vessels during the two-month “bonus season”, while decreasing the size limit for all anglers from 10 to 9 inches, in order to take advantage of the transient abundance of the 2015 year class of scup.

The problem was that, after 2015, recruitment didn’t only drop back to more normal levels, but fell further, with 2019 recruitment being the lowest in the entire time series used to assess the stock.  At the same time, partly because the relaxed recreational management measures adopted in 2017, recreational catch remained high; in 2021, it was far above the recreational catch limit, so high that a 56% reduction would be required to prevent 2022 landings from exceeding the limit again.

Such a steep reduction was extremely controversial; not only the Council and Management Board, but the majority of the biologists on the Summer Flounder, Scup, and Black Sea Bass Monitoring Committee as well, felt that a 56% reduction was excessive, even though, for the Council, it was legally required.  The Monitoring Committee expressed concerns about the “socioeconomic repercussions” of a catch reduction of such magnitude, and instead recommended a rollback of the lower size limit adopted after the December 2017 meeting, which would achieve only a 33% catch reduction.  

The Regional Director of the National Marine Fisheries Service’s Greater Atlantic Fisheries Office stated that, should the Management Board not adopt the full 56% reduction, NMFS would probably have to adopt other measures, up to and including a complete shutdown of the scup fishery in federal waters, in order to achieve a reduction closer to the legally required 56%.

Such controversy could have been avoided had the Council and Management Board not insisted on trying to harvest as many scup as possible at the December 2017 meeting.

Given the unusually large size of the 2015 year class, there was little doubt that the liberal management measures adopted in 2017 would have to be abandoned in a very few years, after the stock began to return to more typical levels of abundance.  And very few anglers were unhappy with the 10-inch minimum size and 40-fish “bonus season” bag limit that was in force prior to the 2018 season; there was little pressure from fishermen to either reduce the minimum size or increase the bonus season bag.

Thus, other than a desire to let anglers catch every possible fish, there was little reason to make any changes to the scup regulations in 2017.  If managers were only willing to let a few more fish die of natural causes, there would have been no need for the 2022 catch reductions that caused considerable controversy and angler discontent.

Yet the ghost of Wilbert Chapman still haunts our fishery management bodies, and sometimes drives managers to find ways to harvest as many fish as possible, even when such levels of harvest don’t make too much sense from a scientific, economic, or human perspective.

It is time for such ghost to be exorcised, and to realize that, at times, not harvesting every last fish does, indeed, benefit mankind.