Sunday, September 29, 2024

NEW STUDY CONFIRMS DOMINANT ROLE OF CHESAPEAKE STOCK STRIPED BASS

 

Fishermen are often optimists who, despite poor fishing conditions and a shortage of fish, still venture out on the water believing that they're going to catch, even if their experience on previous trips would seem to suggest otherwise.  That optimism often spills over into the fishery management arena where, despite all evidence pointing to a declining stock, they believe that all is well, and that next trip, next month, or maybe next season, the fish will be just abundant as they were years ago.

Of course, sometimes that’s not just unalloyed optimism speaking.  Sometimes, it’s a matter of what fishermen want to believe, or need to believe, because their job involves catching fish, either as a commercial fisherman or for-hire operator, and if the fish population isn’t as healthy and abundant as they hope it to be, they’re going to have to be facing more restrictive regulations that are likely to impact their incomes.

Right now, we’re seeing that scenario play out with striped bass.

For many, many years, it has been pretty well accepted that the Chesapeake Bay is the primary striped bass spawning area, which contributes somewhere between 70 and 90 percent of all of the fish in the coastal migratory population.  And the most recent benchmark stock assessment tells us that abouttwo-thirds of the Chesapeake fish are produced in Maryland waters. 

The Hudson and Delaware rivers provide smaller contributions, as does North Carolina’s fish from the Albemarle/Roanoke River complex.  But the North Carolina stock has effectively collapsed, and genetic studies suggestthat the Delaware River has now been colonized by Chesapeake bass, perhapsafter past episodes of hypoxia in the Delaware prevented the river’s original bass from reaching their spawning grounds.  So the Chesapeake stock remains the most important component of the coastal population.

Recently, that has proven to be a problem, as Maryland is now experiencing spawning failure, with itsaverage juvenile abundance index for the past five years the lowest in thehistory of a survey that dates back about 65 years.  While Virginia spawns have arguably been alittle more successful, the last three years there have still seen very lowjuvenile abundance.  While we won’t know how successful the Maryland and Virginia spawns were until sometime in mid-October, I’m getting enough signals—in the form of rumors, in the way people try to change the subject when it comes up, and in what people in the know just will not say—to make me believe that Maryland might well see its 6th consecutive year of below-average spawns this year, although the juvenile abundance index will hopefully be a little higher than it was in the recent past.

However, even if the 2024 juvenile abundance indices for the major spawning grounds turn out to be near, or even above, average, there will be five year classes of fish missing from the population, and a big hole in the age structure of the stock that we will probably begin to feel in 2026, when the largely-absent 2019 year class would normally be expected to exceed the current 28-inch minimum size.

That would normally be problem enough, but the striped bass stock is in even worse straits, as it remainsoverfished, and there is some question as to whether managers will be able to rebuild spawning stock biomass to its target level by 2029, the deadlinecreated by the Atlantic States Marine Fisheries Commission’s striped bassmanagement plan.

Put all of those issues together, and it becomes clear that, if fisheries managers do what needs to be done to rebuild the striped bass population, some very onerous management measujres are going to have to be put in place when the ASMFC’s Atlantic Striped Bass Management Board meets on October 23rd.

Those management measures won’t be welcomed by those who kill bass for a living, and thus tend to focus on short-term harvest rather than the long-term health of the stock.  Such folks already expressed their objections to the more restrictive management measures contained in Addendum II to Amendment 7 to the Interstate Fishery Management Plan for Atlantic Striped Bass.  One of the most common arguments was that as the climate changes and waters warm, striped bass spawning is shifting from the Chesapeake to spawning grounds farther north, including the Hudson River and various New England streams.  

Thus, we saw comments submitted like those of the Stellwagen Bank Charter Boat Association, which wrote,

“Change in environmental conditions are impacting the Chesapeake Bay striped bass spawning ground and climatic shift is impacting the distribution and productivity of spawning grounds further north.  Proactive measures to address detrimental impacts to the Chesapeake Bay and further assessment of other striped bass spawning grounds including the Delaware and Hudson Rivers needs to be conducted to further assess the status of the fishery.  Proactive measures are recommended such as what was conducted to address Atlantic Salmon and spawning forage species that need to be considered with the potential removal of dams located on the Raritan River, Connecticut River and Merrimack River where spawning is evident and/or elsewhere to promote and protect spawning grounds.”

Tom Fote, a New Jersey angler who frequently opposed striped bass conservation measures when he served as a Governor’s Appointee on the Management Board, argued that

“Because of climate change and other conditions in the Chesapeake Bay, I think other areas are producing a greater percentage of the striped bass.  Because of the warming of the water, this may continue to increase.  I have been waiting to see what happens to the stocks in the Kenneback [sic] River since that has always been considered a producing area.  It is also interesting to see if Connecticut’s waters are becoming producing areas.  We know that Canada is having a problem with wild Atlantic Salmon being eaten by striped bass and that may indicate more production further north.  We need to do the necessary research to find out what is happening with the coastal migratory stocks and not just continue to see the Chesapeake Bay as the only producing area…”

Paul Haertel, another New Jersey angler, made similar comments, claiming that

“in the NY Bight area we now have some of the best striper fishing I have ever seen in my life.  This is due to the fact that the Hudson River stock is in great shape.  However, we are being denied access to them because of the declining Chesapeake Bay stock.  I believe that as the population of the Hudson River stock increases so does their range.  They are heading further North, South and East and providing great sport in areas where they never used to travel to.  I suggest you conduct a study to see for yourselves…”

And another fisherman named James Leone, who appears to belong to the commercial sector, commented

“As someone who derives 100% of my income from fishing industry [sic] it would be a devastating blow to be further regulated or shut down a fishery as important as stripedbass [sic].  My concern is that the science needs to be updated because of rising ocean temps in the Atlantic, changes in migration and breeding patterns.  Therefore the science that has been used for many years specifically as pertains to the Chesapeake does not accurately reflect the total population that has moved further north.  I believe that there has to be new research that takes into account obvious climate change before we start further restricting a fishery our industry and coastal communities are dependent on.”

A number of other individuals, many of whom were connected with the for-hire fishing industry, made similar comments, many at in-person hearings held by the ASMFC.  However, no one provided any reliable data in support of their claims of a northward shift, but merely assumed that it was taking place; their requests for additional studies seemed to presuppose that any such research would support their beliefs.

I have written about striped bass many times on this blog, and one of my more recent posts, published last August, addressed the hard decisions that the Management Board is going to have to make at its October meeting.  It received a response from Montauk, New York charter boat captain Rick Etzel, who wasn’t particularly pleased with what I had written, and chose to challenge my statements, saying

“If you think the striped bass stock is in decline, you should step out of your cubicle and witness a spring and fall run.  For someone who claims to be on the water for fifty years your knowledge appears minimal.  The YOY in the Chesapeake and Maryland is down because the fish don’t just spawn there and nowhere else.  They MUST be spawning further north and east in every estuary along the coast.  How else could we be seeing all these different Year classes that you and the scientific community say don’t exist.  You spew as if you’re out there every day but you’re not.  In fact you’re probably nothing more than a weekend warrior professing to save the species.  Do is [sic] all a favor and convince Dr Drew [of the ASMFC’s Atlantic Striped Bass Technical Committee] to go out and observe the fish stock instead of swallowing what she is fed from the scientific community.”

Stripped of all the insults and disdain for fisheries science that characterize the majority of comments emanating from somewhere within the for-hire industry, that particular comment was merely made by someone who is afraid that regulations needed to rebuild the striped bass stock are going to damage his business, and so is striking out against the science, and anyone who supports it, not because he has any data contradicting what the biologists are saying, but instead because he badly needs to believe that the stock is healthy and that the spawning failure in Maryland won’t seriously impact his income.

Thus, the comment “They MUST be spawning further north and east in every estuary along the coast.”

After all, he seems to argue, we can assume that striped bass are successfully spawning somewhere, because they don’t exactly have labels on them specifying their waters of origin.

Except that, in fact, such labels exist.

Every striped bass swimming in our coastal sea, in our rivers, our bays, our estuaries and sounds carries a very clear and distinct label that declares where they were spawned, included in their genetic code.  Biologists can readily read those labels, and newly released genetic research—the very sort of research that many people called for in their comments to Addendum II—conducted by biologists working under the aegis of the University of New Hampshire and New Hampshire Sea Grant, has provided new insights into the origins of the striped bass migrating along the East Coast of the United States.

As scientists have always believed, the overwhelming majority of those striped bass were spawned in the Chesapeake Bay.

The description of the research project reads:

“The migratory striped bass stocks support one of the most popular recreational fisheries on the Atlantic coast.  Identifying the contribution of different spawning populations (or stocks) to the fishery would provide a more thorough understanding of stock dynamics and could enable more targeted, informed management.  Here, we used a genetic approach to determine the proportional contribution of spawning stocks to the striped bass mixed fishery in the Northwest Atlantic between Long Island, NY and Portland, ME.”

The initial research was conducted in 2018 and 2019, when biologists worked with 36 fishermen located along four sections of coast, including the waters surrounding New York's Long Island, the Rhode Island shoreline, the Buzzards Bay/Martha’s Vineyard/Nantucket region of Massachusetts, and the waters between the New Hampshire side of the Merrimack River and Portland, Maine.  Fin clips were taken from 5,400 different striped bass, which

“eventually allowed for a detailed description of when and where striped bass of different sizes and populations are migrating northward and then southward throughout the region.”

With respect to the origins of the striped bass sampled, the researchers determined that

“The Chesapeake Bay and Delaware River fish were too genetically similar to differentiate using our panel [a differentstudy conducted by Massachusetts fisheries managers came to the sameconclusion]; together they contribute 80-88% of the striped bass to the fishery,”

“The Hudson river system contributes 10-18% of the fish,”

and

“1-2% of the fish originated from the Roanoke River or could not be assigned to any of the reference populations.”

The results were remarkably consistent across both years and all four sampling regions, with the contribution of Chesapeake Bay/Delaware River fish ranging from a high of 88.8% in Rhode Island in 2019 to a low of 75.4% in New York in 2018 (it should be noted that the next-lowest Chesapeake contribution was 80.6% in Maine/New Hampshire in 2018; the Chesapeake contribution to New York samples in 2019 was 86.5%).

As might be expected, the Hudson River was the next-highest contributor, with contributions ranging from a high of 19.6% in New York in 2018 to a low of 10.3% in Rhode Island in 2019 (the Hudson’s contribution to New York in 2019 was 11.6%, the second-lowest contribution made to any of the four regions that year).

But it might be the smallest contributions that were the most intriguing.  Although North Carolina’s Albemarle/Roanoke stock never contributed more than 0.4% of the fish to any of the sub-samples (New York 2018), and made no contribution at all in three of the eight sub-samples, the fact that it appeared in any measurable quantities, given the very badly depleted state ofthe stock, suggests that, at one time when the stock was healthy, it might have been a more significant component of the coastal migratory population.

And the fact that New York enjoyed the two highest contributions of fish of unknown origin—4.6% in 2018 and 1.7% in 2019, compared to contributions ranging from 0.9-1.6% for the other six sub-samples—leaves some room to argue that, perhaps, some nearby, as-yet uncredited spawning ground or grounds, perhaps the Connecticut and/or Raritan rivers, might be contributing a very small fraction of the fish to the coastal population, although it’s just as likely that contamination or other problems with some of the samples led to the “unknown” determination.

But the important takeaway from the study isn’t speculation about where a very small fraction of the bass might have originated, but the fact that the Chesapeake Bay/ Delaware River stock is proven to be the predominant source of striped bass for the entire coast, providing over 80% of the bass being caught.

So if the Chesapeake stock collapses, fishermen will not be able to look to the Hudson, or some yet-unnamed rivers in New England to save them from the consequences of a stock collapse that could look very much like the one of forty-some years ago.

If the Chesapeake stock collapses, the fishermen can expect no salvation to come from anywhere else.

The future abundance of juvenile striped bass in the Chesapeake is going to depend on environmental conditions in the spawning reaches, and on the availability of zooplankton for the juvenile bass to feed on when and where they hatch.  No one can predict when favorable spawning conditions will recur, and if and when they do, whether such conditions will coincide with a sufficiency of food for the juvenile bass.

Thus, those who depend on striped bass, whether for food, for recreation, or for their livelihood, would do well to set aside false hopes and unsupported beliefs, and instead support managers’ efforts to rebuild and then conserve the overall striped b ass stock.

For if we get behind conservative, science-based management efforts, there may still be a chance to maintain some sort of fishery until conditions in the Chesapeake eventually improve.

If we don’t, and instead stake the future on the fantasy of new spawning grounds taking the place of the Chesapeake Bay, then we're doing nothing more than setting the stock up for collapse.

I aleady saw the stock collapse once, and have no desire to sit through that show for a second time.  And I can assure you that if you missed the last collapse, and particularly if bass help to pay for your meals and your mortgage, you really, really do not want to see that scenario played out again.

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