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« on: May 13, 2022, 01:33:17 PM »

IMEP #111
Climate and World Food Demands Increase Seafood Roles
The Collapse of Species and Food Security
“Understanding Science Through History”
 “Can Past Land and Sea Case Histories Help Us Now”
From the West Haven Land Trust Meeting on June 8, 2011
The Rise and Fall of Seafood
Growing Population in Cities Leads to Greater Food Demands of Farmers and Fishers
Viewpoint of Tim Visel, no other agency or organization
Ghost Towns and Buried Cities Linked to Climate
Tim Visel - The Sound School – 2018
Capstone Research Area, The Lost City of Teotihuacan, Mexico
Revised to October 2019 - March 2022
This is a delayed report

Much has been written about the Lost City of Teotihuacan, not only by archaeologists but more recently by climate researchers.  This city, about 30 miles northeast of Mexico City today, reached its organizational zenith 800 years before Columbus discovered the “New World.”  This city was already very old.  At first, this lost city was thought to be the result of massive societal and ruling class shift – a possible revolution that so disrupted commerce that the city was abandoned.  However, these investigations found few weapons and noted that conflicts (wars) were rarely mentioned.  Instead what the investigations revealed was a culture placing great importance upon crops; agriculture was prominent.  About ten years ago, researchers decided to take another look, this time at climate change and food security and historical records of how cities were “defeated” by the lack of food throughout time.  Were the last days of Teotihuacan days without rain?  The impact of climate and food security are modern issues that did not escape the passage of time.

Introduction – The Dangers of Dry Farming And Food Security – The Great Plains of Northern America

The 1890’s conservation movement had come at a difficult time – the New World offered immigrants something that the Old World many times could not – land. In fact, it was government US policy then to “grant it out” and even to the point, “land” once populated by Native peoples would be part of its cause and terminology.  Land Grant College Act of 1862 and Timber Culture Act of 1873 and Homestead Act of 1862, which ended in 1986, all relinquished ownership of land to those willing to farm it for at least five years. This was not the case in Europe where land fragmentation occurred and smaller parcels meant a type of agriculture poverty for many in Europe.  Land grants of 160 acres and promotions of prosperous prairie life often did not match reality.  Regardless, European immigrants expanded the frontier into the western lands we call today, The Great Plains, and larger populations of course created the demand for more food.

Irregardless, agricultural researchers warned policy makers about climate concerns of these areas in the 1880’s, the western lands at times had little to no rain. Eastern cities grew quickly and as surrounding agricultural lands were converted to infrastructure, the need of stable agricultural production elsewhere soon increased. Transportation of food to cities by railroad had opened new markets and the ability to serve them.  The western lands therefore were often looked at as the “bread basket” to feed a growing United States. The Homestead Act in 1909 was increased to provide land grants of 320 acres to support dry farming, however, the dangers and concerns of “dry farming” were brushed aside. Agriculture researchers responded and issued written dry farming warnings. Food security was a powerful political and economic force; a hungry population is often an angry population. For example, the shortage of cheap shad to feed factory workers had largely created the need and creation of the U.S. Fish Commission in 1871.  Access to food was an old-world concern, for hundreds of years, food was at times a weapon of war, starving a foe or enemy. Food for urban centers had especially been a weapon of war for centuries, the castle siege, cutting off food was a way to defeat a well-armed enemy behind its castle walls. By cutting off food sources, a surrounding army just waited for defenders to starve. One of the most notable English sieges was of Kenilworth Castle in 1266.  This siege during the English Civil War started on May 26th, 1266 and lasted until December, 1266 with the surrender terms called the “Dictum of Kenilworth”.  Kenilworth Castle was established by Geoffrey de Clinton in Warwickshire in England. The castle was destroyed in 1659 but the names continue here in the towns of Killingworth (once called Kenilworth) and Clinton, CT.

Lost Cities Highlighted as Outcomes of Conservation Failure

The buried and abandoned cities had both captured the imagination of the public in the early 1900’s and caught the attention of those promoting conservation policy as an end result of natural resource misuse. This was frequently mentioned as lost or “buried cities.” Evidence of tremendous urban cities, commercial and transportation centers suddenly were deserted and then buried in sand. Many had linked the abundance of these lost cities to poor resource management, but most likely a climate induced agriculture failure, from a natural cycle and largely outside of farmers’ ability to change it. Most interesting to me were efforts to move water to ancient farm fields, hand dug canals that functioned for a time and then it seemed filled with a gray powder - signs of sapropel from a drought and excessive heat.  It seems as though greater and greater efforts were being made to irrigate these ancient fields with cities that then were suddenly abandoned.  Students who want to investigate an important case history about climate, it is called “The Fields of Teotihuacan” an ancient city about 30 miles northeast of present day Mexico City.  Here was an entire city built around 200 A.D. in an area of minimal rainfall (about 25 inches/year) eight square miles in size that housed a population estimated at 150,000.  The areas surrounding this once prosperous city were irrigated with earth works, canals and ditch works that would rival many modern farms.  The city reached its organizational peak around 650 A.D. with streets, roads and large structures of perfectly cut stone, but was abandoned around 750 A.D.  When the Aztec culture expanded in central Mexico, they found a huge city empty 700 years later in the 1400’s.

Few clues exist as to what happened except a very complex irrigation system that once provided the farmed food for those living near or in the city somehow suddenly failed.  We do have some clues, some researchers have reported finding what appears to be defensive works around key irrigation structures, dams and canals, and small populations continued to exist in the area centuries later around wetter areas and springs.  Some of the city burned and canals abandoned. It is thought that the last days of this once great city were days of no water.  If the irrigation system was diverted or destroyed, famine could happen.  A more likely cause, my view, is that the rains stopped.  A recent paper titled “Location and Orientation of Teotihuacan, Mexico: Water Worship and Professional Space” published in The Penn State University Occasional Papers in Anthropology No. 33 (2016): 25, is an excellent reference for a possible Capstone study on Climate Change and The Lost City of Teotihuacan.  But we have another case history closer to us than central Mexico – the United States’ dust bowl of the Great Plains.  Here we have an example of what happens to agriculture and the people who once depended on it when the rains stop.

Dry Farming Warnings – The 1905 U. S. Yearbook of Agriculture

By the late 1880’s, the farming community already had some bitter lessons about climate cycles.  In fact, the USDA already had a chief of “Climate and Crop Division” it called the Weather Bureau.  Periods of too much rain often included devastating floods and soils so wet that plants and seed rotted in the sun.  Dry conditions could result in dust bowls where crops withered and soil turned into dust.  These were bitter habitat lessons for the farming community and often some of the first tasks of the early agricultural experiment stations were to provide the agricultural community information about plants and climate.  Information about some of the first indications of climate cycles came from early soil scientists’ studies of the mid-Western prairie grasslands.  Here below the grass sod provided clues to the habitat history that was over time in constant motion on the surface.  In fact, it was the examination of prairie peat that came some of the first warnings about “dry farming,” the practice of converting grasslands into farmland.  These examinations often showed periods of dryness and fire followed by wet conditions.  Grasses grew because they could as the conditions of habitat instability (low rainfall and heat) could kill most larger plants and then had fires of the dry grasslands.  The constant change in rainfall over time precluded forests and only those plants that could grow the fastest had largely developed – grasses.  But even that habitat type could quickly change and soil scientists at the U.S.D.A. issued several (and often severe) warnings about “dry farming” and the need for supplemental irrigation.

In 1905, Elwood Mead detailed the hazards of dry farming on pg. 425 in the Yearbook of the Department of Agriculture that contained a section titled “The Relation of Irrigation To Dry Farming.”  It issued one of the first warnings of the dangers of “Dry Farming” to the farm community.  Dry farming must have water irrigation reserves.

“Early failure and its lessons” starts off the section of “Dry Farming.” Here is described some of the first attempts at “dry farming” and Mead states “the three hundred million acres now being settled for agriculture.” The demand of a growing nation clamored for acreage to be farmed.”  Elwood Mead wrote “From all classes come the questions! What methods will make the most of these lands?” Mead, then Chief of Mitigation and Drainage Investigations, gives a brief description of this “Great Semiarid Strip” and the danger associated with “a variety of causes tempting men to plow up the native sod.” With a habitat history of a mini dust bowl of 1883 to 1893 the warning of “early failure and its lessons” in Kansas and Nebraska on pages 423 to 429 - (The 1905 Yearbook of Agriculture) these warnings, unfortunately, were largely ignored.  Mead explains:

“A few wet years, in which fine crops were grown, were followed by a succession of dry seasons. On millions of acres crops shriveled and died, men lost hope and energy through repeated failures, and women and children endured dreary years of poverty and hardship” and mentioned the hot, dry winds of the plains – “The winds are like a blast from a furnace so hot and dry that they change green fields of corn into dry and ratting stalks in twenty four hours.”

The aspect of dry farming detailed by Elwood Mead is that it may take two years of rotation to allow soil moisture to return allowing the cultivation required for planting seed. This “dry farm” required much more acreage than 100 acres or so for the typical family farm that obtained regular moisture of the eastern Atlantic Seaboard. Droughts could still happen. Dry farming would require much more land up to three times that amount to let follow even when rains were sufficient to grow crops at all. Segments of the farm would need to be rotated, even in times of modest rainfall. Here Mead gives us a view of the dry farm under modest conditions.  Page 430, Yearbook of the Department of Agriculture 1905, contains the following:

“But when all this has been said, the fact must be recognized that the dry farm taken alone has not the security of farming under irrigation, or of farming in Iowa or Illinois, where the rainfall is ample. Nothing can be more dreary or discouraging than the aspect of the dry farms home in midsummer without shade trees, without green grass, without fruit, the dead, dusty and life less appearance of the landscape is monotonous beyond measure. It makes one realize that “a world without turf is indeed a desert.”

Four years later, the Homestead Act was amended by Congress for applicants (homesteaders) to receive each 320 acres to promote dry farming. However, the greatest emphasis of Mead’s warning was that dry farming to be successful or sustainable needed alternative water resources, from the ground or surface, it needed irrigation were often ignored – Mead 1905 Report, pg. 429:

“From 1893 to 1888, the writer was a resident of Colorado and after visited the sections where dry farming was being tried. From 1885 to 1898, inclusive, he was a resident of Wyoming and as state engineer, was in official and sympathetic relations with the men farming by rainfall alone in the eastern part of the State. During these years, hundreds of dry farms were visited and an intimate knowledge reached of the bad conditions of home life which the vicissitudes of the dry farm impose on the farmer’s wife and family.”  (And, these were “the good times.” – Tim Visel)

In 1929, Hurd Curtis Willett (who would later document these climate cycles of drought) was just earning his doctorate in meteorology from George Washington University and joins the MIT faculty in 1929, the same years The Great Plains’ rains stopped. Nothing could now stop what Elwood Mead had warned about 25 years earlier; the reserve lands were also under cultivation.  There was no soil moisture bank to draw upon.  Many farmers had cultivated the reserve fields as well.

The grain crisis of 1919 had caused farmers to put more land under cultivation. The early teens had seen grain prices soar, as Europe’s farm fields were filled with bombs, not crops. A starving Europe begged for American western grain, which we provided at high prices. Now in the 1920s as Europe’s agriculture slowly recovered, grain prices plummeted, and to maintain income and keep current loans from eastern banks, farmers just planted more grassland.  The 1916 price of corn was approximately $1.30/bushel; by 1930, it was only 30 cents/bushel.  With declining prices, land value dropped and banks foreclosed on farms by the hundreds; this process was stopped in 1934. The collapse of farm income, loss of bank credit – loans and decline in land value (equity) would worsen the financial panic of 1929.  The Great Depression was first felt by dry farmers, whose yields per acre rarely exceeded 20 bushels.  The huge grain harvests now depended upon 40% export markets and that market was declining.  They were unaware of both the warnings about dry farming and the climate cycles that initiated them.  Dry winds began to blow across the Midwest in the 1900’s.

These same winds would drive devastating prairie fires in 1910, one called the “Big Blowup” and thought to be the largest forest fire, burning three million acres across a wide belt from Washington, Idaho to Montana.  That was part of Elwood Mead’s warning.  He had already seen agriculture’s “lost cities.”  “Whole counties were almost depopulated, what had been thriving towns were deserted” after rains ceased (Annual Report of the Weather Bureau 1896-97). 

Here on the mid-western plains, habitat succession for centuries had not progressed beyond the grasses.  Temperature, moisture and energy (fires) had stopped habitat succession as grasses were the only plants that could re-seed and re-sod these areas.  These were the range grasslands of the Great Plains, but grasslands are inherently unstable habitats although they appear as large areas of habitat stability.  They are not and over time unstable.  Cores of peat soils below the grasslands showed that habitats could change quickly and had over time.  The human experience of what plant habitat failure means for us defined the creation of the Soil Conservation Service and the grass habitat failure, called the Dust Bowl, which saw hundreds of communities “lost” and then buried in sand.  The dust bowl responsibility came to the farm community as the dust storms removed valuable “top” soil containing organic matter and the nitrogen fixing bacteria that allowed grasses to live.  However, the primary reason was that the rains just stopped.

Report of the Connecticut Board of Agriculture 1909 – Conservation Policy

By the late 1900’s, conservation as a public policy had taken hold as western expansion of clear cutting forests and harvest of animals (waterfowl) had changed public perceptions that natural resources had no limits. The Governor of Connecticut, Frank B. Weeks as past practice, was invited to speak at the Connecticut Board of Agriculture – Agricultural Convention held in Harmony Hall, New Haven, CT on December 7th, 8th, and 9th, 1909. (Within four years, the US Mint would release the most symbolic conservation coin as to our natural resource use, the Indian Head or Buffalo Nickel 5 cent coin).

Governor Weeks (not a farmer himself) brought a message to the convention about conservation and includes these comments:

“The conservation movement is receiving a great deal of attention throughout the country, and I may say in passing that I shall leave here at noon to attend the Conservation Convention or, more particularly, the Waterways Convention, to be held in Washington tomorrow and succeeding days. There will undoubtedly be some five hundred delegates present. The President will start the discussion. They will have three days for discussing this matter of national waterways and they may, before they get through, touch upon the matter of the conservation of the soil and of the preservation of our watersheds. The conservation movement has received a great deal of attention – conservation of our watersheds, our waterways, our forests and our soil, and this subject will receive more attention probably during the next few years than most any other that could be brought to the attention of the American people. Our agricultural societies should inform themselves fully upon these great subjects, for the waterway and the forest question has very much to do with the soil. In our country’s history we have passed the milestone of selfishness. We are going forward to build and conserve our resources which were given to our fathers that they may be preserved undiminished and improved for those who shall follow us. We look to our agricultural societies to use every means within their power to accomplish this.  Conservation does not mean to stop using, but wise use, looking toward the need of each
generation.” 

The conservation movement would gain public support as dust storms from mid-western areas could now reach the east coast.  The tragedy of the waste of soil and economic hardships would be told by author John Steinbeck in his 1939 novel “The Grapes of Wrath.”

Conservation Policy and Public Opinion

Because the depletion of natural resources could be a visual experience, occur in print media, photographs and letters to editors, the impacts of man’s use would soon eclipse natural events. It is difficult to imagine today, but Connecticut once had large forest fires that would burn for days largely out of control, and during this warm relatively dry period, fires in Connecticut increased. The movement of water into farm fields increased and Connecticut, with numerous streams and rivers, suffered less in the period of heat from 1880 to 1920. Conservation of natural resources became a national policy and the loss of forests, fisheries and soil soon became an agriculture agenda. Nutrient replenishment, husbandry and game management were old world technologies that did not guide natural resource use. Agriculture had already abandoned a slash and burn approach (New England), and soil science, especially for Connecticut, had become more than a topic of interest; it was essential. The agricultural practices of the plains were far different than what occurred here, but public policy wise, a universal viewpoint was established.

To create an atmosphere of crisis, the conservation movement had already linked resource use to civilization declines. The concept of climate and energy cycles influencing agriculture would happen in just two decades. In the west, the perils of “dry farming” on grasslands would become known as the dust bowl. Climate influencing agriculture here would need another half century, but Connecticut farmers had already realized that productivity was connected to fertilizer and enhancing the capacity of soil, selection of seeds, disease protocols, and the genetic improvement of livestock. Much of this emphasis came from the country’s first Agriculture Experiment Station right here in New Haven, CT.

Governor Weeks, addressing the Agriculture Convention of 1909 (p. 36), closes his comments with the following:

“There is another fact that I am going to leave with you before we take a recess.  A few years ago it became my very great pleasure to listen to a lecture and during that lecture this statement was made that set me thinking. The thought that it suggested I am going to leave with you to think over during the recess. The lecturer made this remark. Speaking of the old, buried countries that archaeologists are doing so much to unearth and explore, where they find the cities and towns buried in the sand, and he said it very forcibly, and it was thought that he brought our move in particular, and which I want to leave with you. He said that centuries ago these same buried cities had the same privileges, watercourse and everything, the same verdure (vigor) and forests, the same as we enjoying today, but they became used up and therefore paid the penalty, they became dead.  That was the result, they became buried beneath the sand. Think that over. Think more of conservation of the resources that we have. I just wanted to leave that thought with you.”

We have no way of knowing how Governor Weeks’ statements about conservation and buried cities met with Connecticut Board of Agriculture attendees, but later in the day, some comments about agriculture in support of cities appears in the minutes - my comments in brackets [T. Visel]:

“The farmer ought to be thankful, and he ought to honor these men who are willing to spend their time to see if they cannot find some way to get rid of some of these causes of loss [pests and diseases, T. Visel]. Now a few men have not realized the immense value of the agricultural interests of the country. They do not think of the values produced, and they do not think how dependent a great many people are upon the farmer’s success. How long would a city like this live if the farmer was entirely wiped out? How long would the city live? It could not live for a week [New Haven, T. Visel]. We are entirely dependent upon them. Our business prosperity is dependent upon them. Take this one thing of our own corn crop during the last year of 1909. According to the agricultural department, our crop of corn is valued at one billion seven hundred and twenty-four million. It was raised out of the earth in about one hundred and twenty days. That crop added fourteen million dollars a day to the wealth of this country. Fourteen million for every day. Just think of the values that are being produced. How dependent we are upon that. I should like to have time to dwell upon it, but cannot dwell upon such matters now. It seems to me we should be gratified by the fact that men are willing to devote their time to finding out the cause and prevention of so many of these things which occasion us farmers great loss.” [The 2020 corn crop of the US generates $61 billion or $167 million/day/year.]

The bias of conservation would grow over the next century – the wise use and careful management of natural resources would be replaced by a policy of nonuse. This would lead to a greater dependence on natural resources from other nations – foreign lands. Nowhere perhaps is this so apparent from the use of seafood – as marine resources of our coasts decreased and at times conservation policy became enforced seafood imports now soared.

This natural resource concern led to the practices of selective cutting, soil nourishment, rotation of crops and to minimize predator/pest cycles and fires. These are found to be at the root of agriculture failures and have a climate connection. The rise and fall of fisheries is also in the fisheries literature – a geographic bias of fish movements as climate changes, fish swim, habitat quality declines in one region as habitats improve in others. Connecticut once boasted of a Halibut fleet, but that fleet moved north, following the fish as they moved north as well.  Small fishing vessels that fished Long Island first had water circulating live “wells” that allowed modest catches to be delivered, alive or fresh, to markets.  But as temperatures rose in the later 1880’s, these “live wells” became “dungeons of death” as put forward by Nelson J. Huntley in his book calling them “Black Holes of Calcutta” about Connecticut’s once famed Halibut fishing fleet (1906) in Niantic, CT.

In the 1890’s, oyster boats were painted white to reflect sunlight lest the decks became so hot, they became unbearable. Bacteria thrived also in this heat, impacting both oyster growers and milk producers (See “Clean Milk, Pure Oysters for Cities”: Have We Forgotten Our Environmental History?, March, 2014).

But what did the public see about changes in farming and fishing – farmers tilling soil and fishers setting nets. It was a visual picture of these industries, but behind the picture was the rise and fall of predators (pests), diseases, growing seasons that held too much rain or not enough, and fish that moved to more favorable habitats. The public did not see these pictures, which could be decades in the making.  In time, the rise and fall of agriculture and fisheries (aquaculture) was seen to be a human event, subject only to human impacts and decisions. That is a huge problem with environmental policy – (my view) the public has become isolated from a long-term climate perspective and provided and explanation that our actions alone govern farm and fish supplies.

The rise and fall of seafood often has a natural climate link, but related to habitat quality and habitat changes that may take decades to “picture.”  The early researchers of the Great Plains saw in sod cores the remains of past climate cycles.  Even today, dry bed streams exist in our area as reminders of once powerful flows of water now absent, but leaving stranded boulders exposed in an ancient creek or stream bed that is now “dry.”

To complicate an accurate climate impact picture, only short-term human impacts are highlighted, the impact of chemicals, land use, and resource use. While these impacts are real and at times substantial, they pale before climate cycles, floods/droughts, heat or cold, energy of many storms or periods of few storms.  These patterns can last for centuries.

It is natural over time to have habitat change – it is unnatural not to. Although many accounts still mention the tilling of marginal grasslands as the reason for the 1930’s dust bowl, the dust bowl was part of a climate drought cycle for hundreds of years. Lobsters died off in the Long Island Sound in 1898 during a prolonged hot period. They died again a century later in 1998 after another long hot period.  Many reports mention the 1998 lobster die off but very few mention the 1898 lobster die off or raises the issue that such die offs may be cyclical, subject to climate impacts, or in fact “natural” (See Appendix #4).  That is what the early agriculture researchers mentioned, looking at sod cores as evidence of past change.  They saw evidence of these past cycles in layers of ash and dust between those of prairie peat.

Although the Great Plains farmers could not prevent the drought, they helped magnify its impact.  It took decades to repair the soil loss, which gave rise to a new federal effort to conserve the soil with conservation in its name, the Soil Conservation Service, later renamed in 1994 to The Natural Resources Conservation Service.  Many acres of sand/dust were later reclaimed as productive farms and soil structure rebuilt but it took a return of “normal” rainfall and access to supplemental water and crop rotation to do it, precisely what Elwood Mead suggested over a century ago.  When the dust bowl occurred, fires raged and entire towns were abandoned, tens of thousands left, cities lost to civilization and stark reminders to us of what can happen when the rains stop.  Hurd Willet at Massachusetts Institute of Technology would be the next one to address that point in the decades to follow.  In 1953, he would develop the term “polar vortex” in a book titled “Climate Change: Evidence, Causes and Effects” edited by Harlow Shapley, Harvard University Press.  His work is credited with the public awareness of cycles and weather patterns known today as the NAO.

The Concept of a Marine Drought

Although I read about the dust bowl in high school and later taking earth science coursework, the concept that a climate shift was possible in Long Island Sound or in the ocean did not occur to me.  It wasn’t until I met John Hammond that the concept of climate impacting fisheries became real.  I had participated in two fisheries, lobster and oyster, where one benefited from cold and the other from heat.  I had started looking at lobster catches while I was still lobstering and oyster catches in 1981.  In fact, it was John Hammond who urged me in 1981 to look at the 1880 to 1920 period (See Appendix #5: Rhode Island letter, dated April 22, 1982).  In time, I was to learn that climate and related storm intensity did influence habitat quality and parameters of what we term “ranges.”  All climate conditions change and that some species could experience a habitat failure “dust bowl” even under water as described in Appendix #3.


Appendix #1
NAO and Tilefishing


FISHERIES OCEANOGRAPHY            Fish. Oceanogr. 8:1, 39-49, 1999
The 1882 tilefish kill — a cold event in shelf waters off the north-eastern United States?
ROBERT MARSH,1 BRIAN PETRIE,2 CHRISTOPHER R. WEIDMAN,3 ROBERT R. DICKSON,4 JOHN W. LODER,2 CHARLES G. HANNAH,2 KENNETH FRANK2 AND KEN DRINKWATER2
1 James Rennell Division for Ocean Circulation, Southampton Oceanography Centre, Empress Dock, Southampton, SO14 3ZH, United Kingdom
2 Department of Fisheries and Oceans, Bedford Institute of Oceanography, Dartmouth, Nova Scotia, Canada B2Y 4A2
3 Department of Marine Geology and Geophysics, Woods Hole Oceanographic Institution, Woods Hole, MA 02543, USA
4 The Centre for Environment, Fisheries and Aquaculture Science, The Laboratory, Lowestoft, Suffolk NR33 OHT, United Kingdom

ABSTRACT
A mass mortality of `warm-water' tilefish in the Middle Atlantic Bight between April and August of 1882 suggests an episode of extreme cold in the shelf waters off the north-eastern United States. This cooling is hypothesized to be a consequence of enhanced equatorwards transport of cold water in the Labrador Current, coincident with a minimum in the North Atlantic Oscillation (NAO) index during the early 1880’s.
Although there is little direct evidence for this historical event, an analogue for the 1880’s cooling is found in the 1960’s, at the most recent NAO-index minimum. Post-1945 observations in the Middle Atlantic Bight/Gulf of Maine region reveal changes in winter baroclinic circulation between cool and warm decades, with greater equatorward penetration of south-westwards flow along the shelf-edge during the cool 1960’s. Over the period 1934–77, the NAO is found to account for 17% of the interannual variance in Labrador Current transport around the Grand Banks.
Proxy evidence for the cold episode of the early 1880’s is sought. Records of bottom temperature in the Middle Atlantic Bight region are reconstructed using stable oxygen isotopic analysis on the annual bands of shells of a bivalve mollusc (Arctica islandica) and an empirical model of covariability with local air temperature. The result is confirmation of the presence of anomalously cold water during the early 1880s.
Key words: Labrador Current, NAO, tilefish kill


Appendix #2


 

Commercial Shellfish Landings Decline Likely Linked to Environmental Factors, Not Overfishing
October 25, 2018
Combined landings between 1980 and 2010 dropped by 85 percent
Researchers studying the sharp decline between 1980 and 2010 in documented landings of the four most commercially-important bivalve mollusks – eastern oysters, northern quahogs, softshell clams and northern bay scallops – have identified the causes.
Warming ocean temperatures associated with a positive shift in the North Atlantic Oscillation (NAO), which led to habitat degradation including increased predation, are the key reasons for the decline of these four species in estuaries and bays from Maine to North Carolina.
The NAO is an irregular fluctuation of atmospheric pressure over the North Atlantic Ocean that impacts both weather and climate, especially in the winter and early spring in eastern North America and Europe. Shifts in the NAO affect the timing of species’ reproduction, growth and availability of phytoplankton for food, and predator-prey relationships, all of which contribute to species abundance. The findings appear in Marine Fisheries Review.
“In the past, declines in bivalve mollusks have often been attributed to overfishing,” said Clyde Mackenzie, a shellfish researcher at NOAA Fisheries’ James J. Howard Marine Sciences Laboratory in Sandy Hook, NJ and lead author of the study. “We tried to understand the true causes of the decline, and after a lot of research and interviews with shell fishermen, shellfish constables, and others, we suggest that habitat degradation from a variety of environmental factors, not overfishing, is the primary reason.”
Mackenzie and co-author Mitchell Tarnowski, a shellfish biologist with the Maryland Department of Natural Resources, provide details on the declines of these four species. They also note the related decline by an average of 89 percent in the numbers of shell fishermen who harvested the mollusks. The landings declined between 1980 and 2010 are in contrast to much higher and consistent shellfish landings between 1950 and 1980.
“A major change to the bivalve habitats occurred when the North Atlantic Oscillation (NAO) index switched from negative during about 1950 to 1980, when winter temperatures were relatively cool, to positive, resulting in warmer winter temperatures from about 1982 until about 2003,” Mackenzie said. “We suggest that this climate shift affected the bivalves and their associated biota enough to cause the declines.”

Since the late 2000s, the NAO index has generally been fairly neutral, neither very positive nor negative. As a consequence, landings of all four shellfish species have been increasing in some locations. Poor weather for bay scallop recruitment in both 2017 and 2018, however, will likely mean a downturn in landings during the next two seasons.
For more information, contact Shelley Dawicki

Last updated by Northeast Fisheries Science Center on September 10, 2021


Appendix #3
Sulf Clam Dieoff
MFR PAPER 1356 EC 21 New Appendix #3

Review of Oxygen Depletion and Associated Mass Mortalities of Shellfish in the Middle Atlantic Bight in 1976
FRANK W. STEIMLE /

ABSTRACT-In summer and autumn of 1976, mass mortalities of shellfish occurred in a 165-km long corridor of severe oxygen depletion paralleling the New Jersey coast from 5 to 85 km from shore. Mortalities of surf clams, Spisula solidissima, the most severely affected species, were estimated in excess of 140,000 t. Alteration of normal migration patterns of lobsters and several species of finfish was also noted. A series of anomalous meteorological and hydrological events (particularly early warming of surface waters resulting in early thermocline development, and a massive shelf-wide phytoplankton bloom) superimposed on an already stressed coastal area, was considered to be responsible. The occurrence is particularly significant because the continental shelf of the Middle Atlantic Bight, from Cape Cod to Cape Hatteras on the east coast of the United States, contains the largest known stocks of ocean shellfish of any comparable coastal area of North America.

INTRODUCTION
 
Mass mortalities in the sea are relatively common events and always attract the interest of the scientific community as well as the public. This interest may be based on a concern for the loss of a fishery resource, or the nuisance or health problems created by the decaying animals. Very often it is difficult to identify the cause of mass mortalities because most investigations begin after the fact, so the conditions which lead to the mortalities may have been altered or dissipated by the time studies begin. The majority of mass mortalities are very localized, often confined to a particular bay or estuary, but a few can be widespread, sometimes affecting hundreds of square kilometers of ocean.
 
An environmental event of heroic proportions, leading to mass mortalities of many marine species in a 12,000 km2 area of the continental shelf off the Middle Atlantic coast of the United States occurred during July through October 1976. Investigators were able to detect conditions that were lethal to marine life; these conditions were extreme oxygen depletion and hydrogen sulfide formation in bottom waters.

In the central part of this zone, oxygen values were zero, and hydrogen sulfide was detected below the thermocline. Oxygen depletion persisted until October, when lower surface temperatures and mixing, after disappearance of the thermocline, gradually reoxygenated the bottom water. Mortalities of fish, lobsters, molluscan shellfish, and other benthic invertebrates were observed. The sedentary forms, surf clams, ocean quahogs, and sea scallops, suffered the greatest mortalities. From almost continuous surveys, it was estimated that 69 percent of the surf clam population off the New Jersey coast, representing some 143,000 t of meats, had been destroyed by October, with significant but lesser mortalities of ocean quahogs and sea scallops. Lobster catches were reduced by 30 percent during the period. The New Jersey coast was declared a resource disaster area in November by the Federal government because of this event.

Hydrogen sulfide was also evident in an apparent upwelling of anoxic bottom water along very restricted portions of the immediate shoreline in central New Jersey. Hundreds of fish of several species, including sharks, were trapped along the beach and killed. A period of strong westerly winds, pushing the inshore surface waters offshore, was thought responsible.

EFFECTS ON SHELLFISH AND OTHER BENTHIC POPULATIONS- Beginning in late July 1976, assessment of the impact of the anoxic event on the surf clam stocks began. Signs of stressed surf clams were noted by divers as early as the weekend of 4 July. These were clams that were not embedded in the sediment but were lying free on the surface. Several later trawl surveys also found live, but gaping clams.

The lobster, Homarus americanus, industry off New Jersey suffered. Some of the inshore stocks were killed, and the annual shoreward migration of offshore stocks was interrupted. During the months of June through September, normally the most productive months of the year, landings declined an average 30 percent compared with the same period /978 KILOMETERS 020406; 10 20 30 NAUTICAL MILES NEW JERSEY 74° period in 1975. The inshore pot fishery, which operates within 20 km of shore, was most severely affected. Lobstermen stated that few offshore migrants entered the fishery in 1976 (Halgren, 1977).

Other benthic populations were affected by the anoxic water. Effects on the benthic infauna were most noticeable in the H2S zone, with reduction in numbers of species and numbers of individuals. Species to species variability in survival was noted, with a number of polychaetes and sea anemones quite resistant to prevailing extreme environmental conditions.
 
The survival of marine invertebrates, including shellfish, in oxygen-depleted waters, and in the presence of hydrogen sulfide, has been examined, and additional experiments are being conducted by the National Marine Fisheries Service. Earlier studies (Theede et aI., 1969; Davis, 1975) and preliminary results of current studies indicate survival of clams for periods of several weeks in water which approaches zero D.O., but shorter survival in hydrogen sulfide environments. These experimental findings agree with field observations in 1976. Surf clams began showing signs of stress early in July, but mortalities were not reported until the middle of July. The extended period of anoxia, combined with hydrogen sulfide, resulted in 100 percent mortality by October at stations in the most severely affected zone along the central New Jersey coast.

Oxygen depletion has occurred sporadically in Mobile Bay, Ala., one of the largest estuaries on the Gulf of Mexico. Stratification of the water column over highly organic bottom results in summer oxygen depletion, and occasionally, because of winds, the water mass impinges on beaches. Fish and invertebrates may be trapped in the anoxic water near beaches, often in a disoriented or moribund condition, where they are taken in great numbers by residents. The shoreline phenomenon is called a "jubilee." Thirty-five such occurrences were reported by Loesch (1960) between 1946 and 1956, but newspaper accounts go back to the 19th century (the earliest being in 1867). May (1973) has reviewed the history of such events and finds no increase in their frequency in recent years. He carried out detailed oxygen determinations during a "jubilee" in 1971 and found large areas of the bay with less than I ppm dissolved oxygen in bottom water. Mortalities of fish, crabs, and oysters were observed.

The Ceratium population appeared to decline sharply by July, and its contribution to bottom oxygen depletion in June and July was strongly indicated by the accumulation on the bottom of I cm or more of a brown flocculent material, which consisted to a large extent of dead Ceratium. Additionally, the observation in late spring and early summer that much of the bloom was concentrated at or below the thermocline indicates another possible mechanism of oxygen depletion, since the organism may exist heterotrophically. Ceratium is not grazed upon by many planktonic herbivores, so the persistent bloom over a period of several months meant the accumulation of large amounts of oxygen-demanding organic material in the water column, and the gradual accretion of dead organic material on the bottom. All of this oxygen consuming material, when combined with the unusual hydrographic events mentioned earlier, seems to provide a reasonable explanation for the observed extreme oxygen depletion in 1976 (Mahoney, 1977; Malone, 1977). Annual phytoplankton blooms are now a reality in sections of the New York Bight, probably in part at least as a consequence of organic loading of coastal waters, particularly from the Hudson River. The mean residence time calculated for the New York Bight is 100-250 days and estimated daily chemical inputs from the Hudson River estuary complex alone are 520 tons of nitrogen and 138 tons of phosphate. Sewage sludge dumping and other human sources of nutrients have been estimated to augment these figures by only minor amounts (< I0 percent). In total though, when natural productivity of coastal waters is locally enriched by nutrients of human origin, a condition of increasing eutrophication can develop-and oxygen depletion can be a consequence. It does seem, however, that the extent and duration of the 1976 Ceratium bloom in the Middle Atlantic Blight would indicate that it did not occur in response to local nutrient inputs, but was rather a shelf-wide long-term phenomenon.

Appendix #4
Lobster Dieoff of 1898 and 1999: A Look Back
Two Lobster Collapses in 100 Years
States Rush to Build Lobster Hatcheries to Prevent Extinction in 1904

The New York Times
LOBSTERS ARE SCARCE.; The Natural Supply Dying Out and Artificial Propagation Necessary to Prevent Extermination.
From The Bangor Commercial.      July 24, 1899

Notwithstanding the efforts of the United States Fish Commission to restock the waters along the New England coast with lobsters, the annual supply of 2,500,000 pounds from Maine is nearly exhausted, and the Government, having become alarmed, has sent the Fish Commission steamer Grampus, Capt. Griffin, to this coast to buy female lobsters and transplant them at the hatcheries in Gloucester.

The New York Times
Scientists Are Mystified by Deaths Of Lobsters in Long Island Sound
By David Barstow            Oct. 18, 1999   

Marine experts suspect that a mysterious pathogen has killed tens of thousands of lobsters in Long Island Sound this fall.
The die-off, described as the worst to hit Long Island Sound in nearly a decade, has alarmed hundreds of lobstermen in New York and Connecticut and has prompted extensive laboratory testing by state and Federal environmental officials.
Marine experts say they are unsure of the full scope of the die-off, which was reported late last week in several Long Island newspapers. Offering what he described as a conservative estimate, Mr. Young said ''tens of thousands'' of lobsters have died already, with roughly 8 of every 100 captured lobsters coming up dead. Blue crabs and rock crabs, too, are dying, officials said.
Lobster boats first began reporting the deaths about six weeks ago, particularly in the western third of Long Island Sound.
''I pulled up 300 pots today and I didn't see anything,'' said Bart Mansi, 43, a lobsterman who has 2,500 traps in Long Island Sound.




Appendix #5



State of Rhode Island and Providence Plantations

Department of Environmental Management
Division of Fish and Wildlife
Washington County Government Center
Tower Hill Road
Wakefield, R.I. 02879
April 22, 1982

Timothy Visel
Cape Cod Extension Office
Railroad Avenue
Barnstable, MA 02630

Dear Mr. Visel:

   Dick Sisson asked me to respond to your letter of March 23 requesting information on seed oystering in upper Narragansett Bay between 1880 and 1920. I have enclosed that information which I have been able to sift out from the upper strata of our archives. Although this information contains some references to the seedy aspects of the oyster industry, I am not aware of any more specific information.

   The Brooks book (reference enclosed) has apparently been stolen from the URI Library (Pell). I saw it several years ago, and I seem to recall a description of the Narragansett Bay oyster industry. I suggest you try to find a copy through your local sources.

   A large quantity of oyster lease records was turned over to David Maslyn, an archivist at the URI Library (Kingston, RI 02881) several years ago. This included maps of leased grounds covering some of the period you specified, as well as blueprints of the triangulation stations used in establishing the boundaries. This may be a source of information useful to you, but I don’t remember any facts pertaining to oyster seed production. Of course, that doesn’t mean it isn’t there.

   Please let me know if I can be of any further assistance in dredging out information for you.

   
Sincerely,

John Karlsson
Marine Biologist

JK:ps
Enclosure
Rekeyed by Taylor Samuels, Sound School, Communications, Dec. 18, 2014                                     

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