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« on: June 20, 2018, 02:10:45 PM »

The Search for Megalops- Special Report #1
Habitat Clocks and Growing Seasons
“You Don’t Need To Be A Scientist To Report”
April 2018
A Possible Climate Clock for The Southern New England Blue Crab
View All Megalops Newsletters on the Blue Crab ForumTM
 Northeast Crabbing Resources Thread
The Blue Crab Megalops Series - The Sound School
New Haven, CT


A Note From Tim Visel

Colder Waters and a Decreasing Blue Crab Population account from J.L. McHugh, 1972:

“In the waters of New York, the blue crab, Callinectes sapidus, is near the northern limit of its range…Landings have declined steadily but irregularly, since the maximum recorded of about 1.6 million pounds in 1880.  No commercial catch has been recorded since 1961.”

“In Chesapeake Bay, with major fluctuations, the blue crab catch has been increasing for about 35 years (roughly following the growths of healthy eelgrass – T. Visel).  It has been suggested that the increased catch has been caused by increased abundance generated by nutrient enrichment in estuaries (McHugh, 1969) as was suggested also for striped bass (Mansueti, 1961) … It is interesting to speculate that the enrichment of coastal waters and estuaries in the middle Atlantic region of the United States from domestic and industrial wastes may have stimulated blue crab production for awhile, then became a limiting factor as eutrophication proceeded too far.”  [See Marine Fisheries of New York, Fishery Bulletin #3, 1972, Vol. 70, page 591]

This account describes a declining habitat clock for the blue crab in southern New England 40 years ago. What it does not mention was an absence of blue crabs in the colder middle 1870s.

Introduction

By 1912, two decades into the “Great Heat,” an 1880 to 1920 period had southern species such as the blue crab and tarpon were caught in Rhode Island waters.  The appearance of “southern” species in “northern” waters had caused alarm in Rhode Island and lead to the creation of the Narragansett Bay Survey in 1898.  But “our” fish, such as cod were moving north, and also caused alarm to those north and east of our coasts far to the north of our western Atlantic shorelines.  An account from the east coast of Greenland (1912) contains this section:

“When the first codfish appeared at Angmagssalik (Greenland) [Tasiilaq today, east coast and south – T. Visel] in Greenland in 1912, it was a new and strange fish to the Eskimos and Danes who lived there.  [The name of this small village, which dates to 1472, was from “ammassat” or capelin, a cold-water fish.  The year 1912 would be the peak year or close to it for southern New England blue crab landings.  The heat also caused a record number of icebergs and this year is infamous for the loss of the Titanic].  “Within their memory, it had never (cod – T. Visel) before appeared on the east coast of the island – Greenland.  But they began to catch it, and by the 1930’s, it supported so substantial a fishery in the area that the natives had become dependent upon it for food.”

But by 1966, the codfishing industry had declined in Greenland.  More recent information shows a climatic upturn in codfish off the coast of Greenland in 2009 - nearly a century after the first appearance.  In 2014, the TAC total allowable catch was 10,000 metric tons.  The 2016 catch was the highest in 25 years (ICES-CIEM, Published 13 June 2017) at 34,000 metric tonnes.  The 1912 catch estimated was 5,000 metric tonnes – ICES estimates (2017).  The surge in codfish north does seem to share the same habitat clock as our recent surge in the blue crab here – 100 years – warm climate cycle.

The source for the 1912 account of the appearance of cod is from “The Sea Around Us” by Rachel Carlson published in 1951 – pg. 169 – The Global Thermostat – in a section about climate cycles.  Signet Science Library Books, Tenth Printing, September, 1963, Oxford University Press.

Rachel Carson’s book “The Sea Around Us” was completed after a U.S. Fish and Wildlife Service trip aboard the Albatross III and dedicated to Henry Bryant Bigelow, an oceanographer who pioneered several fisheries fields – the Bigelow Fisheries Laboratory was named after him in Boothbay Harbor, Maine.  The chapter titled “The Global Thermostat” contains a large section on climate cycles and connections to our fisheries, including the collapse of the Hanseatic herring fisheries of the Middle Ages.  1912 was the same year a previous researcher Otto Petterson published a paper titled “Climatic Variations in Historic and Prehistoric Time” based on a theory that alternating periods of mild and severe climate cycles are connected to patterns in ocean circulation and tides.

“The Sea Around Us” would remain on the New York Best Seller list for 86 weeks.  Rachel Carson’s employment with the United States Bureau of Fisheries was first to analyze field reports on fish populations and series of history articles.  She was by today’s employment descriptions a fisheries biologist.  Rachel Carson’s second best seller “Silent Spring”, a decade later (1962), is largely credited with writing first about the bias of the “funding effect” of science supported by “financial inducements” and the danger of biological resistance to chemicals.  The second book raised public awareness around the growing use of insecticides and, in part, was the foundation of public support for the Environmental Protection Agency (EPA) ten years after it was published.

It is the book “Sea Around Us” in which climate cycles were connected to fish populations.


Low Point for East Coast Blue Crabs – The Winter of 1957

I do not remember much from the winter of 1957 except perhaps the cold.  On the shore of Lake Pontoosuk in Pittsfield, MA, the negative NAO brought bitter cold to New England.  I recall ice fishing on the lake and tunneling into the plowed snow banks, which were several feet high.  Icecicles forming on the window, looking at this frozen lake, were massive hanging from the rooftop and touching the ground, causing my father to clear them often.  He had joined Western Electric and was reassigned that year to work on Peru Massachusetts Communication Microwave Tower, built on Peru Mountain starting in 1956 in the community of Peru, Massachusetts.  The red and white metal tower was part of a microwave communication system, then a part of the “Cold War” advanced communications system, being built along mountains on the U.S. east coast.  Pictures of the entrance to the tower showed a narrow road with snow banks at least eight feet high on either side during the winter of 1957.  The selection of this small Massachusetts community was a good one.  Peru’s elevation is about 2,000 feet, but its climate is severe.  Even its current description today contains phrases like “windswept, barren, and having a shorter than average growing season with harsh winters caused by its high elevation.”  The site was perfect for a communications tower, but according to my father, the weather and winds meant brutal conditions for workers.  From some climate resources, the 1957-1958 winter had Boston receiving 45 inches of snow – 100 inches of snow in Worcester, winds of 50mph could create high snow drifts.  So high, that this effort had its own snow removal trucks. 

In a recent report “A Monumental History, Stories of the Berkshires,” (K. Bolduc Unity College 2017) mentions that in the 1930’s, the area schools would close for most of the winter until spring.  In the middle 1950’s, some parts of Peru had yet to obtain electric lines and reach these high mountain ridges.  It was the ridges that made this line of sight tower communication possible; it also meant a short construction time period, and on the coldest of days, only a few hours of work was possible.  After the base section was completed, the ironworkers, according to my father, were all Native Americans from upper New York State.  This cold had gripped all of New England as well, colder temperatures, powerful Northeasters and summer hurricanes.  It was this time period that the Chesapeake Bay blue crabs dipped to its lowest catches, and New England’s blue crab catches were noticeably poor or absent.

But in this cold climate cycle, bay scalloping soared on Cape Cod and also the Poquonnock River in Groton, CT, which some newspaper accounts put its 1956-1957 catch at 30,000 bushels (most town shellfish landings are not included in state statistics).  The catch of American shad,  Alosa sapidissima, would peak at 12 million pounds in 1958.  Colder water also had returned rainbow smelt, Osmerus mordax, to the Horse Neck River of Greenwich, CT.  What Native Americans termed the “ice fish,” smelt were often the first returns to streams just as winter ice cleared.  Most likely, Greenwich has the most interesting climate cycle habitat history.  In the 1870’s, it was considered New England’s “Bay Scallop Capital” but by 1912 Greenwich was filling its salt marshes, wiping out the last mosquito habitats responsible for malaria in the early 1900’s to the 1950’s and a surprising return of rainbow smelt to its shores in this cold period (Visel and Savoy, 1989).
George McNeil, the last surviving New Haven oyster grower business of the previous century, had already moved much of the City Point oyster operation to the mouth of the Hammonassett River, one of the last of the salt rivers to still obtain an oyster set (the marshes in the area would heat up the water giving the oysters a local yet small habitat refugia), but now fought leaves covering his last crops of seed oysters.  [The picture of the oyster from Long Island Sound in Paul Galtsoff’s 1964 Bulletin on page 93, was one that John Hammond purchased in 1962 from George McNeil, his last year of oystering.]

The cold would impact John Hammond on Cape Cod as well, working with William Shaw of the U.S. Fish and Wildlife Service in Oyster Pond, Chatham, the site of his oyster grant to raft culture oysters.  In an attempt to increase growth and survival rates in the absence of commercial oyster sets, the first hatchery methods were developed (See IMEP #8 posted on February 12, 2017 and IMEP #45 posted on February 2, 2015). 

William Shaw writes in 1962 about off-bottom oyster culture experiments also assisted by John Hammond, in Fishery Bulletin #197, Vol. 61-Raft Culture of Oysters in Massachusetts (1962), on page 486 is found this section:

“Several bushels of cultch were transferred to Oyster Pond River (Chatham, MA – T. Visel) strung in galvanized wire, and placed on the raft by October 5, 1957.  All but two strings of Wareham River oysters were destroyed in the storms of January 1958.”

John Hammond told me that the ice in the river was so thick that the raft holding the off-bottom oysters was moved to the pond and anchored but that the ice sheared the suspended oysters on wire when they moved and the raft did not (John Hammond, Personal Communication – T. Visel).

Furthermore, on page 492, Shaw mentions:

“The danger of floating ice in the winter also makes the river (Oyster Pond River) undesirable for raft culture.”

The winter of 1957-1958 was especially harsh.  William Shaw could have not picked a worse climate period to conduct trials of off-bottom raft culture of oysters.  In addition to massive outbreaks of the Polar Vortex that nearly eliminated the Florida citrus crops, heavy snows hit New England (three waves of cold polar air made it to the Gulf of Mexico with temperatures in the 20’s).  The blizzard of February 15-16, 1958 had snow falls in excess of 20 inches followed a month later by the March 18-21, 1958 Nor’easter, making the winter of 1957-1958 forty plus inches – the most snow filled since 1917-1918 (The warm winter of 1997-1998 for comparison had about an inch of snow).  Yet the growth of off-bottom “3-D” oysters was much faster as mentioned in my brother Raymond Visel’s report on off-bottom oyster culture in 1976 on the same subject. In the same report, he predicted off bottom culture would someday be larger than bottom culture.

John Hammond on Cape Cod told me that winter storms in 1957-1958 cut Monomoy Island in half, leading to a shallow inlet and then hazardous navigation conditions for the fishing fleet.

The clash of the polar air into the Gulf of Mexico colliding with strong westerlies energized coastal lows in the latter part of 1958, making the coastal lows move into a very high pressure area in Baffin Bay.  This, in turn, caused winds to gales to be most severe along the east coast casting warm air onto polar cold air resulting in heavy snows.

By the time Spring arrived, according to Mr. Hammond, most of the raft oysters (experiments) were gone.  The winter of 1957-1958 is written up in many historical reports.  It started very warm, a “split winter” then a polar vortex developed now associated with the North Atlantic Oscillation, “NAO” negative phase, which in mid-winter dropped to a negative 2.7 allowing at this time cold polar air to sink south, forming a dip in the upper level jet stream that resembles a horseshoe – the polar vortex.  By the time the spring warmth blocked this arctic jet, New England was ready for its “spring.”

Mr. Hammond also noticed that in this very cold winter “the growing season” was now very short.  (Much of the off-bottom method was to shorten the habitat clock).  He also gave me Luther Blount’s report on off-bottom culture, which he obtained while I as working on the Cape and said off-bottom oyster culture was perhaps feasible if the winters remained mild as the 1970’s to 1980’s. Mild winters favored warm water species post 1972 – including the blue crab.

With recent reports of the Chesapeake Bay blue crab winter dredge survey, indicating a massive winterkill (some sizes 42%) of the blue crab, the chemical change in marine soils could indicate bacterial shifts back to the 1950’s when oxygen levels increased with cold water.  Our recent winters have become colder, sea water temperatures the last three springs have been cool.

The 1950’s however, were great for the “cold water species” as those that needed warmer waters left our waters.  These changes are reflected in the fish catch statistics over the past century.  A key indicator of climate cycles perhaps is the change of benthic bacteria – similar to those bacterial changes found in terrestrial soils after forest fires.  These bacterial changes have a biochemical measure, the amount of soil sulfide.  It is the level of sulfide in marine Sapropels that is suspected in winterkill, more appropriately described as a sulfide kill.  And, the sulfides have a direct role in the health of eelgrass, Zostera marina, very important to the blue crab megalops in southern bays.  We can see examples of massive habitat shifts with trees and soil condition indicators in which the bacteria provide soil its sulfides.  It is the sulfides in marine soils now suspected in the decline of eelgrass (See Appendix #3) and it’s die-off or die-back.

The onset of the German forest dieback (Waldsterben) occurred during an extended period of low rainfall and very acidic rains and local conditions of sulfur dioxide emissions, which also caused acidic conditions in forest soils.  These acid soils were thought to have mobilized aluminum and allowed fungal infections to damage tree root tissue, resulting in crown weakening, reduced growth, and in some cases, sulfide browning.  Some researchers have mentioned the increase in soil sulfides as damaging root tissue in plants and a possible connection to climate cycles that, in turn, impact plant life.  Sulfides in wet or peat soils can be traced to bacterial reactions, and much information exists for the culture of rice in wet submerged soils and its relationship to the sulfur cycle, a facet of bacterial growths. 

The climate factor of heat and cold alters bacterial soil growths.  After forest fires, for example, soil bacterial populations are destroyed by rapid oxidation heat (the fire).  Long periods of cold/ice may also cause oxygen depletion and sulfur-reducing bacteria sulfides anoxic “kills” in shallow waters (ice covered) also prime blue crab overwintering habitats.  In both extreme heat – low oxygen jubilees and extreme cold – as ice blocks the light needed for photosynthesis, resulting sulfide events then happen.  The summer high heat jubilee – or the winter sulfide “winterkill” in salt ponds with thick ice are both related to oxygen and bacteria of Cape Cod.  The sulfides in marine soils have already shown that they influence eelgrass, Zostera marina, and the blue crab (See Jubilee Blue Crab (Callinectes sapidus) Survival in Simulated Seagrass Habitats Zostera marina and Ruppia maritime by Kylie Smith, 2017, Appendix #3) megalops suitable habitat.

Severe cold may cause shallow water habitats to fail for the blue crab from ice induced anoxic conditions (sulfide) and blue crabs in deeper oxygen-containing waters survive.  Often in the historical literature, habitat shifts in populations (seafood) proceed changes in fishing gears as illustrated by shifts of spears to fykes then trawls of New England in the cove and bay winter flounder fisheries.  The onset of colder conditions may have caused a switch in blue crab gear types.  For example, trot lines were replaced by crab traps as crabs stayed in deeper areas for longer times before moving to (if present) the warmer shallows.  The Blue Crab Crash of 1915 extended into the 1920’s.  The colder weather most likely caused a temporary habitat refugia for the blue crab, causing larger concentrations in deeper warmer waters and, thus, perhaps led to the creation of the crab trap habitat refugia was perhaps what caused Benjamin F. Lewis to experiment with one in the cooler 1920’s. 

The end of the Great Heat 1880-1920 brought colder energy winters that saw the blue crab catch to drop to its lowest point in Chesapeake Bay in 1957 to 1959.  The Chesapeake Bay blue crab catch again dropped to a low point in 1960 during a similar bitter cold period.  By 1965, with moderating temperatures, harvests increased only to drop significantly two years after Hurricane Agnes.  Sulfide events are thought to have killed eelgrass, a major blue crab megalops habitat type in the late 1990’s.  Blue crabs and “clean and green” eelgrass appear to share similar habitat clocks, those governed by temperature and energy.

The blue crab fishery has also perplexed crabbers and fishery managers for over a century.  Although most think overfishing and pollution are the principle factors that govern blue crab populations, while that is true in some cases man made toxins can reach lethal levels and overfishing can occur with long lived species (such as the southern conk fishery) it is more difficult to show those impacts with migratory or shorter lived species, those that live in waters the most susceptible to habitat change – the shallows of bays and coves.  These species are tough to predict or model because many fishery models are based heavily upon reproductive (egg) capacity (potential recruitment) the numbers of eggs produced rather than habitat quality – the environment – or how many of those eggs can survive, Survival – linked to temperature and energy.

It is a discussion that dates back to the founding of the US Fish Commission itself in 1871, and heightened in the late 1890’s.  It is in the late 1890’s in which blue crab habitat abundance moved far to the north in times of brutal heat waves, mild winters while lobsters failed in these same habitats.  The pollution indicators do not hold up for the blue crab, as lobsters for example fled Narragansett Bay for deeper cooler waters, blue crabs steadily increased in the 1900’s, they became very abundant in the same water if pollution was damaging to the blue crab then it would not be able to replace lobsters.  Rather pollution (human) often has a small part and if you examine a cohabitant species, the oyster it also shows the same pattern.  In the 1870’s Connecticut’s winters were often brutally cold and the winter of 1872-73 saw temperatures go to 30 degrees below zero for days at a time (most of Connecticut’s valley fruit – apple orchards were killed by this cold and two years later led to the cattle Catastrophe of 1875.  Here hundreds of cattle purchased by Connecticut farmers from Texas came to Connecticut loaded with very small ticks, which spread disease into native herds and neighboring states.  A Texas Fever account of this event is printed in the CT Board of Agriculture and suggested bacterial disease spread by southern ticks).  Because Long Island Sound waters did not support heavy oyster sets in the 1870’s (except in the most shallow and warm salt ponds and coves) seed oysters also termed bedding stock were imported into Connecticut by the hundreds of thousands of bushels.  Oysters could live here; it is just habitat limitations that prevented dense sets.  That would also change in the 1880’s as waters warmed into The Great Heat (1880-1920) oyster sets along the shore now improved and by the 1898-99 years oyster sets were immense and widespread.  The 1899 set was called the set of the century, that same year the lobster fishery was “in ruin.”  In this great heat or hot term, New England residents rushed to the shorelines for cool breezes and cool waters.  Shore communities sprung up to accommodate this human rush to the sea during this “heat”.   

It is at this time that Connecticut beach hotels began to advertise shore dinners, pavilion open air dances and for those more inclined to water activities a crab skiff and net.  In eastern Connecticut with its coastal coves became popular spots to head out with lanterns and dip blue crabs – at night.  Oysters also surged in abundance and heavy sets occurred in areas four decades before held ice in May.  Pollution as described in the literature was largely uncontrolled – yet the oyster and blue crabs, both species which live in the shallows, surged (Industry reports of milk and oyster disease reflect increases in spoilage - See Clean Milk and Pure Oysters For Cities, Blue Crab ForumTM, Environment/Conservation Report #6, posted on July 23, 2015).  By the 1950’s, a colder weather pattern with more storms replaced the quiet almost storm free warmth of 1890’s.  Blue crabs and oyster populations declined (so did in time war time pollution) while bay scallops filled these cultivated and cleaned bay and coves, oysters disappeared along with many of the blue crabs.  In time the Connecticut commercial catch statistics stopped for the blue crab, in 1931.  By 1950 the crab catches of the 1890’s were all but forgotten.  Marine growing seasons because they transcend more than one crop year should be considered “clocks” instead as John C. Hammond on Cape Cod felt that way – retired “oyster planter” a term when Cape Cod did not get an oyster set but had to import “southern plants.”  To raise a crop in the coves and bays took more than one year – or growing season. 

Habitat Transition of Mapping Sapropels – Fuel for Marine Habitat Succession

This aspect of habitat clocks was more suitable for marine farmers and more resembled orchards than “row” crops.  Here, farmers tend to small oysters, watching them grow.  Because of this, Mr. Hammond and oyster farmers kept notes about the habitats they farmed, and like land, saw habitats “succeed” over time.
 
In these shallow high energy habitats have the most transitory aspect of shore life and species succession.  While a severe forest fire starts terrestrial habitat succession (secondary), the chances of several forest fires in the same area are slim, there is simply just not enough fuel (carbon in plant and tissue) to support them.  However coastal habitats have no such “fuel” limitation here the habitat (primary) successional processes can be repeated in the same area with devastating impacts – hurricanes.  The shallow habitats soils can be tossed, rinsed and re-cultivation occur without limits of rapid oxidation.  We can follow species movements into such high energy areas especially the grasses in this case eelgrass.  1982 Winter flounder/blue crab fish kill occurred in green pond Massachusetts Falmouth and is a good example of what happens when cultivation energy stops and waters become warm.  Like forest fires, habitat clocks could stop or start in a process that could take decades.  Some areas in the coastal zone will never have time to reach tertiary successional or climax species.

The vegetation of shallows cannot be considered a permanent habitat type, as the Hurricane season of 1955 had Hurricane Connie and Diane hit New England only 8 days apart showed how this happens.  (These rains caused catastrophic flooding in CT leading to President Eisenhower declaring Connecticut a major disaster area on August 20, 1955) moved tremendous amounts of organic matter and storm waves cultivated marine soils.  Eelgrass quickly moved into these cool “rinsed” habitats but would be later eliminated by hot sapropel filled habitat decades later largely part of a natural reduction of organic matter process governed by climate cycles – patterns, not “us.”   Such habitat successional processes are large transitions and dependent upon temperature and energy profiles beyond our control (The 1955 Connecticut floods would help create the Flood and Erosion control federal legislation acts).  Just as grass habitat successional processes are tied to forest fires, they also respond to marine shallow habitats to storms.  It is natural therefore in high energy habitats to see much shorter habitat successional processes.  Since 1812, eelgrass has seen four such cycles as represented in the historical fisheries literature and can now be connected to climate induced temperature and energy cycles – not as much to any human activity.  In fact in habitats of low energy, the application of energy can improve soil conditions for eelgrass, eliminating fines, opening soil pores and reducing marine soil sulfides.

As climate patterns change so does habitat clocks – our blue crab reversal is an example but others exist – quahog /oyster, tautog/black sea bass bay scallop/soft shell clam.  We can follow marine habitat clocks by monitoring its “fuel” the organic marine deposits of compost.  As on land, oxygen bacteria can at times be overwhelmed by organic matter; it accumulates on forest floors, leaves, logs, sticks and branches.  Organic matter is not quickly recycled it may be to dry or too hot and wet, but it time it becomes fuel for massive fires – especially in dry periods.  In marine habitats, organic matter from land also accumulates.  In time, it can also overwhelm oxygen bacteria as these humus deposits were harvested for land (soil) application (See “Marine Manures From The Sea” printed by the New Haven Agricultural Experiment Station, 1917) and have two bacterial reduction pathways – one for oxygen and one for sulfur.   We can see the sulfur bacteria pathway in the swamps and bogs of inland areas – dead trees and the silver tree trunks still standing in them.  The farm community long ago noticed the value of oxygen bacteria and those cultures of bacteria living below grasses were and harvested as bacterial inoculants for those soils poor in bacteria.  Organic matter turned into terrestrial soils did not directly feed the plant, but used to feed the oxygen bacteria that allowed plant nutrients (ions) to pass into the root tissue.

In times of heat and wet conditions, oxygen bacteria can die off and be replaced by sulfur strains.  This is the black root rot of submerged soils or the black sulfide layer in poorly drained athletic fields.  This condition of black sulfide root rot in turf management has created the need for turf advisories, such as those issued by Cornell University.  It is why farmers noticed that wet manures sealed from oxygen leaked ammonia while those mixed with air (oxygen) yielded nitrate – a plant nitrogen compound of value.

This bacterial battle between sulfur and oxygen in soil is an old one on land and shallow seas.  It is the story of peat farming or salt hay harvests, shown by draining the water from peat so that oxygen bacteria can live, and produce plant matter of value.  A flooded field will kill plants, but more importantly also its oxygen requiring bacteria, and without them, plant growth is slow or nonexistent – sometimes for years.

When the United States had dry hot periods 1880-1920 forest fires ravaged towns and villages, which created soil erosion.  The fires, if intense enough, could kill the oxygen requiring bacteria (ORB) leaving soils cleansed of bacteria and with little plant “cover.”  Agricultural schools soon devoted much study into the rebuilding of “forest soils” these soils so consumed by fire that little could grow and with changing climate patterns – cooler and more rain quickly eroded these soils (floods) with often devastating consequences.  Research turned to plants that could grow the fastest with shallow root systems that could stabilize these loose soils the quickest, the grasses.  Grass has shallow root systems so that if any oxygen bacteria could grow it would grow here first in the first two or three inches where oxygen could first penetrate these burned soils.  Some grasses quickly outcompeted others and those were soon selected for trials and seed purification. 

Research into restoring forest soils soon focused upon “cover” plant grasses, and the species best suited for quickly establishing root systems to hold these soils in place from rains.  The Agricultural Experiment Stations of the first land grant universities studied the restoration of forest soils, including the Northeastern Station (Amherst, MA) in 1923 and 1927 The Allegheny Forest Experiment Station, of Pennsylvania. 

Early forest researchers would mention the loss of commercially valuable timber, but agricultural interests soon noticed soil loss or soil burial caused by rapid soil movement after fires (described as mudslides) devastated field crop soils as well.  Although valley soils frequently had soil events that had made them tillable, floods could happen again and floods were long recognized as both “damaging” and later “beneficial.”  It soon became apparent that restoring plant cover was essential as so as they jump-start habitat succession.  That is, we would help the re-vegetation process by planting grasses that were the “most aggressive” in habitat dominance. In marine studies, eelgrass shares many of these aggressive attributes.

We have other examples of habitat clocks in the farm records.  Despite the warnings of early soil scientists that “dry farming” should be delayed in the 1900’s until analysis of mid-western (sod) peat could be studied and that cycles of dry periods were evidenced, these dry farming warnings went largely unheeded.  In the decades ahead, forest soil study would be eclipsed by the study of agricultural soils following a habitat clock we today call the “Dust Bowl.”  Here in a huge belt of grass – certain types of grass followed forest fires much as eelgrass followed hurricanes.  We can also learn from root structures as a climate indicator.  These aggressive grasses, such as cheatgrass (Bromus tectorum), put out shallow “hairy” lateral roots, taking advantage of shallow moisture and quickly moving into soils cleared of secondary and tertiary plant covers (mechanical or natural). 

Plants that are aggressive resemble a lateral root with hairs that quickly anchor loose soil (considered an attribute to control soil erosion) but is aggressive to farm monocultures, and on land, can fuel grass fires damaging to more stable and less combustible growths, an ecological detriment.

It is the opportunistic monoculture characteristics that, at times, can include the creation of natural biocide toxins to other plant competitors with root symbiont bacteria.  In other words, to extend succession, they attempt to kill competitors.  The above factors are what make “crabgrass” such a foe to those grasses, which need more nitrogen, more moisture and produce less seeds.  For instance, cheatgrass, Bromus tectorum, can produce 400 pounds of seed per acre, prefers low nitrogen, and well-drained coarse soils.  It is a fierce competitor to other grasses and has a “weed” status to those that desire other grasses.

When you examine basic morphological characteristics of quick cover plants, they share certain attributes; they are usually shallow-rooted, resilient to wide plant growth parameters (dry periods –disturbed soils), spread by root hairs or radial patterns, as well as flower seeds.  Quick cover research conducted by the U.S. Department of Agriculture and the Bureau of Land Reclamation and several Agricultural Experiment Stations involved native and non-native grasses and trials that sometimes lasted years.  Selection processes included those that could form monocultures, as the primary goal was to bind loose soils as quickly and efficiently as possible (USDA Yearbook, 1902 to 1908 Issues).

What researchers often did was to gather plants that have evolved certain quick cover characteristics and evaluate them for cover use characteristics.  Decades later, the product of this research is available as a commercially sold “quick lawn” (no trade endorsement implied) grass seed mixture that grows quickly and also succeeds quickly.

Certain characteristics for terrestrial (agriculture) soils and some marine soils may exhibit similar tendencies, especially to plant toxins, including sulfides.  That is apparent with eelgrass, an important “cover” plant for the blue crab.  Many of the same characteristic of terrestrial grasses are shared by eelgrass and could help blue crab populations grow as succession starts.

The Problem for Models – Climate Cycles

By the 1940’s United States Fish and Wildlife researchers had apparently come to conclude that natural factors, not catches, had come to define the changes in blue crab abundance especially in Chesapeake Bay.  Fish and Wildlife Service Conference of the Division of Fishery Biology January 27 to 31, 1947, Conference Proceedings Issued March 1947, Washington, DC.  Attendees included George A. Rounsefell, who would publish a book on fisheries management titled “Ecology Utilization and Management of Marine Fisheries,” Paul S. Galtsoff – The American of Eastern Oyster in 1964, James Gutsell The Natural History of the Bay Scallop 1930, and Victor Loosanoff, who connected oyster spat falls to climate cycles in 1967 and Eugene Sorber, head of the fish laboratory in Leetown, West Virginia) on page 27 contains this section: 

“The blue crab of Chesapeake Bay exhibits wide variations in abundance that cause large losses to the industry.  Restrictions on the catching of adult egg-bearing crabs did not remedy this condition.  Research has just discovered that those variations in abundance are caused by changes in the survival of young crabs rather than by the number of eggs spawned.  This survival is influenced chiefly by stream flow, especially in the James River, there is a very promising prospect that further studies of the manner in which crab survival is influenced by those flows that make it possible to raise the average abundance of crabs in the Chesapeake Bay through regulating stream flows by means of flood control and power dams now proposed by the Corps of Engineers.  The reimposing of restrictions on the catching of egg-bearing crabs which was popularly advocated would have cost the fishermen nearly a million dollars a year without increasing the supply of crabs.”

This except in the appendix is part of a much longer discussion that has also followed the lobster industry for also a century, is it the egg or is it nature (See Appendix #6).  Most of the management techniques for fish and shellfish carried from land to sea with one disadvantage – the same habitat factors do not always apply.  On land in temperature cold seasonal areas we have selected crop seeds that are fast growing (seasons) and mature from seed in a year – corn for example.  And, efforts were made ensure egg or seed supplies in case of crop failure.  Lobsters can live to be a hundred or more some estimate 200 years.  Here lobster crop failures occurred after decades of habitat change.  While most put the blue crab life span of 5 to 7 (we may need to revise that every soon) years, its shorter life span makes it more “responsive” or vulnerable to rapid catch level fluctuations from habitat change.  It can build quickly and decline just as fast – it produces more eggs.

That is why the United States Fish and Wildlife Service researchers had given up on the “egg” approach in the 1940s but now put a greater emphasis on habitat as weather or climate (1947).  Serious blue crab research had started in the 1920’s but with changes in climate, heat, cold, floods or drought, changes to populations did not match recruitment, reproductive spawning potential or catches from protecting the “egg.”  In fact, just the opposite had occurred, believing the blue crab was more vulnerable to climate than reproduction success.  It is extremely difficult to model life history with so many environmental factors.  We had a similar experience in Connecticut (East Lyme and Waterford) in the early 1970’s regarding a estuarine flow chemistry model for the Niantic River between East Lyme and Waterford, CT with three major organizations, UCONN, the US Coast Guard and Connecticut College all working to produce an estuarine model for the Niantic River – they could not do it, much to the disappointment of all those involved (personal communication Sung Feng of UCONN to Tim Visel, 1980’s).  The multiple factors (variables) of storm tide, rain, temperature and storms had created so many different outcomes that a consensus “model” for expectations of salinity, oxygen, tides and flushing could not be achieved even for a river.  These efforts are described in a Coast Guard Bulletin by Ron Kollmeyer, 1874 (AStudy of the Niantic River Estuary, Report No. RIDCGA29, and were done in an effort far too short (time period) to gather all of the necessary information to address variables caused by climate cycles.  It is the time lag between storm and temperature events that tends to minimize the importance of climate cycles described by Edward Bruckner as 35 year-long periods of cold wet weather between cycles of warm dry weather in Northern Europe (Stehr, NICO: Hans Von Storch (2000) Edward Bruckner “The Sources and Consequences of Climate Change and Climate Variability in Historical Times”).  It is also perhaps why the climate cycle approach of Hurd Willett at the Massachusetts Institute of Technology only recently has been re-examined for polar vortex events in North America and the NAO.

The long-term approach for climate events are not new.  What measures have we used to determine the frequency of 500 year floods is the soils, not 5 or 10 years records of rainfall observations.  They were not long enough to pick up long-term flood events and the same bias exists with many estuarine models, the variables of climate and energy make short-term observations – “brittle or noisy.”  The fact that thet cannot accurately predict cause and effect because they just do not have the time series necessary to perform those tasks.  One area that seems to be a resource here is the examination of Native American shell middens.  In them lies the shellfish habitat history along our coasts.

That is why I believe there have been so much attention to the large system wide blue crab population models and its response to the egg (which is good and supportable) but neglected almost totally long term habitat or climate (a mistake, my view).  That is why blue crabs models are often described as “noisy” a term that models use to explain authors of data points to random to collect, or the term “brittle” that the model is over responsive within other model parameters in it that have be “weighted” or assigned value not equal to the response – rainfall for instance not weighted the same impact as storm energy etc., finally for those who read about models the term “recalibration” is often used to denote a model failure, but not termed as such (many efforts to recalibrate models are accompanied for additional funds request to do so to that if perhaps adjustment – a much better term to use for additional funds - no explanation needed here). 

Cold temperatures have returned to the eastern seaboard and models that did not weigh temperatures or habitat quality will become “brittle” and non responsive - may I suggest that we begin to finish what the US fish and Wildlife had concluded 70 years ago – that it is just not the egg and begin to look at habitat quality determined by climate cycles and that climate is both periodic and long term?  If the negative phase (cold/storm) NAO continues we have a chance not seen since the 1950s to do so - my view.  I respond to all questions by email at [email protected]

Indian River Lagoon – Sapropel Study

“It’s not muck” is stated at the beginning of Dr. Trefry’s half hour presentation “Running Amuck: Our Six-Decade Legacy to the Indian River Lagoon” (John Trefry, Florida Institute of Technology, May 11, 2016).  This presentation details the impacts of this “black mayonnaise” on coastal habitats and fish and shellfish in them.  The Indian River Lagoon was one of the case studies that was the foundation of the Environment and Conservation Series on the Blue Crab ForumTM.  The role of the sulfur cycle and sulfur-reducing bacteria was minimized (my view) in estuarine research articles after the late 1970’s.  These bacterial strains do not need elemental oxygen the way we do to break down sugars and proteins, they utilize sulfate an oxygen compound in sea water and they will never run out.  Sulfate in sea water is described as non limiting – in heat as oxygen levels drop, sulfate reducers take over a point I examined in the post E/C #7 Salt Marshes a Climate Change Bacterial Battlefield posted 9/10/2015 on The Blue Crab Forum™, Environment and Conservation Thread) oxygen and sulfur bacteria in fact struggle (fight) to maintain habitat dominance – in heat sulfur “wins. ”  The bacterial reduction process in high heat can produce toxic substances, alter the marine soil pH, and are at times pathogens themselves to seafood and even “us.”  As witness the rise in vibrio concern in high heat.  The European research community is now focusing attention on vibrios that live in sapropel – the black mayonnaise marine compost (humus) the subject of many of my newsletters.  Vibrio bacteria have been linked to lobster shell disease (see also Icky Blue Crab shell rot) the chitinolytic vibrios.  The flesh wasting necrotic infections in winter flounder Angullarum beneckea and these strains associated with shellfish in high heat Vibrio vulnificus and one subject to swimmers itch or blood fluke or flatworm parasite (Schistosome) also all concerns in shellfish harvesting areas.

For blue crabbers, marine bacteria in Sapropel is of special concern and is receiving increased research attention but is not unknown to the research community.  In the 1930’s researchers (many of whom connected to the growing petroleum industry) wrote about sulfur- and sulfate-reducing bacterial reactions in the 1930’s, almost a century ago.  Chief amongst these researchers was Claude E. ZoBell of Scripps Institution of Oceanography University of California, LaJolla, CA.  Zobell (1939) comments on the bacteria in marine sediments:

“Bacteria that decompose or transform proteins, lipins, cellulose, starch, chitin and other organic complexes occur in marine sediments.  These bacteria tend to reduce the organic matter content of the sediments to a state of composition more closely resembling petroleum although methane is the only hydrocarbon known to be produced by the bacteria.  The precipitation of solution of calcium carbonate as well as certain other minerals is influenced by microbiological processes that affect the hydrogen-ion concentration.  Other bacterial processes influence the sulphur cycle and the state of iron in the sediments.”

Oxygen injection into marine soils made the growth of sulfur bacteria difficult if not impossible.  Storms accomplished this, cold water rich in oxygen, mixing/sorting soil particles as well, and we can alter habitat richness by mechanical agitation (soil aeration) mostly from shell fishing.  The historical accounts mention the positive impacts of shellfishing – improving soil circulation, increase soil pore capillary action improved pH and allowing space for healthy growths of shellfish (stunting).  One aspect mentioned in the historical fisheries literature is fishers mention how beneficial it is to “work the bottom” to increase soil circulation because they could see the positive impacts – clams grew better faster and in shell hash shells were firm and strong.  I don’t think shellfishers thought about controlling pH, sulfur bacteria or cultivation of marine soil holding habitat succession to favor shellfish sets or growth, but that is what happened (hand rakes and tongs to do this, as well as hydraulic lifts or jets). 

Marine soils and how they succeed in high organic low energy environments has a direct linkage to blue crab habitat quality.  It is the sulfate-reducing bacteria that release sulfides and create a marine compost which is now linked to major fish and shellfish diseases, Vibrio bacteria and cysts forming HABs, parasites even the parasite scourge of oysters MSX seems to have a sapropel link.  The change of sapropel dominated by oxygen - surface humus to sulfur reduction (a Sapropel) has been known for over a century.

Its presence and association to nitrogen (TMDL formation) the sulfur cycle and now plant sulfide toxicity promises to rewrite what we understand about what bacteria organic matter reduction in shallow waters in heat and in cold.  That is because most of the nitrogen cycle TMDL work did not include temperature or energy and the relationships to the build up and putrification of organic matter or the formation of sapropel from it. [Many problems have recently occurred when fossilized sapropel containing pyrrhotite was used in concrete foundations in Connecticut and then produced sulfuric acid when exposed to air and water, the same reactions detailed in the agricultural history – sulfuric acid soil formation].

In some bays and sounds, large amounts of nitrogen were misclassified as human sourced, while in cold, large amounts of nitrogen may be “missing” as oxygen requiring bacteria growth slows. 

The role of bacteria in marine soils is so critical to understanding blue crab habitat quality.  The entire segment of Claude ZoBell’s work is reprinted in Appendix 1.

Is The Winter of 1957-1958 The Same As 2017-2018?

The winter of 1957-1958 is often described as a “split winter” – the fall season relatively mild and the later segment snow-filled.  It is the sharp difference between southern jet stream and interaction of the arctic jets that strengthen coastal storms.  The last three New England winters resemble those “split” winters.

With the recent winters cooler and cold water denser, we may see sapropel washed from bays and coves, marine soils naturally cultivated and marine soil health (pH) improved.  If long enough enhanced, marine soil conditions will be reset for the hard shell clam or quahog, and if cold and ice continues to increase the removal of fines, organic particles will produce less acid bottoms conducive to the bay scallop and the hard shell clam – quahog.  One of the chemical indicators of faster growth is the movement of calcium ions measured by the soil CEC- Cation Exchange Capacity.

These strong natural storm events cultivate and rinse tens of thousands of acres of marine soils in a single storm event.  Multiple events can dislodge worms and other benthic species that it is thought to allow clam spat to survive in low predator cultivated marine soils.  The bacteria will be different and a calculated reduction in Vibrio, which thrive in low-oxygen conditions, perish with oxygen.  The sea or marine soils are rejuvenated and dislodge cysts and spores (disease) into an environment too cold for maturation. 

That is the basis for the habitat clocks described by Mr. Hammond – nature’s way of restoring marine soil health.  These changes, however, are not good for the blue crab or oyster, which does better in warmer, low energy periods.  The habitat clock for the blue crab may be ending after a series of colder and storm filled winters, here similar to those of the 1950’s.  At least it fits the habitat climate history. 

I respond to all e-mails at [email protected].  All observations of blue crabs and habitat conditions are important.

APPENDIX 1  Recent Marine Sediments

LONDON, THOMAS MURBY & CO., I, FLEET LANE, E.C. 4  1939

OCCURRENCE AND ACTIVITY OF BACTERIA
IN MARINE SEDIMENTS

CLAUDE E. ZoBELL
Scripps Institution of Oceanography, University of California, La Jolla, California

ABSTRACT

Aerobic as well as anaerobic bacteria are found in marine bottom deposits. They are most abundant in the topmost few centimeters of sediment below which both types of bacteria decrease in number with depth. A statistical treatment of the data on their vertical distribution suggests that aerobes are active to a depth of only 5-10 centimeters whereas anaerobes are active to depths of 40-60 centimeters below which they seem to be slowly dying off. However, microbiological processes may continue at considerably greater depths owing to the activity of the bacterial enzymes that accumulate in the sediments. The organic content is the chief factor which influences  the number and kinds of bacteria found in sediments.

Bacteria lower the oxidation-reduction (O/R) potential of the sediments. Vertical sections reveal that the reducing intensity of the sediments increases with depth but the muds have the greatest reducing capacity near the surface. Three different types of oxygen absorption by the reduced muds are described, namely, chemical, enzymatic, and respiratory.

Bacteria that decompose or transform proteins, lipins, cellulose, starch, chitin and other organic complexes occur in marine sediments. These bacteria tend to reduce the organic matter content of the sediments to a state of composition more closely resembling petroleum although methane is the only hydrocarbon known to be produced by the bacteria. The precipitation or solution of calcium carbonate as well as certain other minerals is influenced by microbiological processes that affect the hydrogen-ion concentration. Other bacterial processes influence the Sulphur cycle and the state of iron in the sediments. The possible role of bacteria in the genesis of petroleum is discussed.
DECOMPOSITION CAUSED BY BACTERIA

Various physiological or biochemical types of bacteria have been demonstrated in the sediments that are capable of attacking most kinds of organic matter present in the sea. The rate and end-products of decomposition of the organic matter depend upon environmental conditions and the types of bacteria that are present. Waksman and Carey (49) have shown that diatoms, Fucus, alginic acid, copepods and other marine materials are utilized by bacteria with the rapid consumption of oxygen and the production of carbon dioxide and ammonia. More resistant fractions of marine plants and animals such as lignins hemicellulose-protein complexes may be only partially decomposed to give rise to marine humus (50).

Approximately one-fourth of the bacteria isolated from marine sediments are actively proteolytic (18,56) as indicated by their ability to attack proteinaceous materials and in so doing liberate ammonia, hydrogen sulphide and carbon dioxide. Presumably the topmost layer of sediment is the zone of greatest proteolytic activity below which there is a gradual, but not very appreciable, decrease in the nitrogen content of the sediments (30). According to Trask (45) amino acids and simple proteins constitute a very minor part of the organic-matter content. Hecht (23) reports that most simple proteins are completely decomposed even under anaerobic conditions and are not converted into adiopocere. He records that about 90 percent of the nitrogen content sediments is due to chitin. Chitinoclastic bacteria are widely distributed (57) throughout the sea but chitin is only slowly attacked by bacteria even in the presence of oxygen and it may be more resistant under anaerobic conditions.

Most simple carbohydrates are readily decomposed (54) by the bacteria that occur in bottom sediments. Under aerobic conditions. the end-products of the fermentation of carbohydrates are chiefly carbon dioxide and water. In the absence of oxygen, carbohydrates may be attacked and thus yield organic acids, methane, carbon dioxide, hydrogen and other products. Buswell and Boruff (9) noted the production of acetic, butyric and lactic acids, alcohol, methane, hydrogen, and carbon dioxide from the bacterial fermentation of cellulose under anaerobic conditions. Several types of cellulose-decomposing bacteria (48, 49, 51) have been isolated from bottom deposits but very little is known concerning their metabolism. The fact (45, 46) that less than 1 percent of the total organic-matter content of recent sediments is carbohydrate, whereas ancient sediments contain none, is indicative of the vulnerability of this class of compounds to bacterial attack. However, much remains to be done to ascertain the end-products of the reactions.

Perhaps bacteria have a greater influence than any other form of life on the hydrogen-ion concentration and O/R potential of sediments; properties that in turn tend to modify both the chemical composition and physical characteristics of the sediments. They may deplete the oxygen as noted above, they may liberate nitrogen from nitrites or nitrates and they may produce carbon dioxide, carbon monoxide and methane in appreciable amounts.

APPENDIX 2

Effect of Burning on Forest Soils –
H. A. Fowells and R. E. Stephenson (1934)

A century ago researchers studied forest soils and the impact of burning – by investigation fast growing grasses.  A more recent Colorado State University Cooperative Extension Fact Sheet, “Soil Erosion Control after Wildlife (Wildfire)” by R. Moerich and J. Fusano, reviews these fire impacts and early research.

One factor is the wax content of the leaves, depth of leaf litter, and soils high in clay tend to at first repel water negative charge.  This layer is present, results can be seen by a drop of water, it will roll off – and many times takes a frost to crack this layer.  Erosion also breaks this layer a disturbed or cut soil surface allows the first grasses some of which uniquely suited to such cut or disturbed soils.  Digitaria sanguinalis (crab grass, crab finger grass) can bring alarm to these involved in lawn care, but it is actually a grain species and cultivated in Northern Europe.  It produces a high protein seed that is a forage for animals (Poland) and hand harvested at times for human consumption (Polish Millet).  Its role as a grass, which tends to be a monoculture, grows in soils considered poor and low moisture has made it a feared foe of lawn care.  Most homeowners consider it a nuisance but its resistance to cutting, and dry conditions has endured it to be an aggressive dominating successive plant – quickly taking over soils exposed to its seeds.  This has been associated with those soils low in bacteria.  Once individual plants sprout its ability to put out surface roots (runners) in hot soils those that have direct sunlight (no roof canopy shading) and low moisture make it a successive plant.  In time however, crabgrass loses coverage when secondary low canopy plants develop, especially cedar trees.  They moisten the soil and trap organic matter.  They, in turn, relinquish cover to an oak history forest centuries later.
APPENDIX  3
Juvenile Blue Crab (Callinectes sapidus) Survival in Simulated Seagrass Habitats (Zostera marina and Ruppia maritima) by Kylie Smith ([email protected], University of Colorado, Boulder)
Reprinted permission granted on April 27, 2018, Kylie R. Smith

“Hypoxia affects the physiology of Zostera and Ruppia. Low oxygen (LO) conditions negatively impact the survival and growth of Zostera, especially in the presence of sulfides in sediment (Holmer & Bondgaard, 2001). Sulfate reducing bacteria produce hydrogen sulfide during anaerobic decomposition of organic matter (carbon) in marine sediments (Canfield, 1993).
Sulfate reduction typically occurs deeper in sediments than oxic respiration, or aerobic decomposition. The relatively lower amount of oxygen in seawater compared to sulfate allows sulfate reduction to occur longer than oxic respiration. Ultimately, the amount of decomposed carbon on continental margins is about equal for sulfate reduction and oxic respiration (Canfield, 1993). Sulfides and LO reduce Zostera’s photosynthetic rates, and sulfides rot young meristematic cells (undifferentiated cells analogous to stem cells in humans) (Holmer &Bondgaard, 2001). LO reduces Zostera’s shoot densities and root sucrose (sugar) reserves. More sucrose accumulates in Zostera leaves under hypoxic conditions because sucrose transport to roots is blocked (Holmer & Bondgaard, 2001).
Sulfides are phytotoxins at high concentrations. Young Zostera and Ruppia leak oxygen from their roots into the surrounding rhizosphere (sediments directly surrounding roots) to reduce exposure to sulfides (Jovanovic et al., 2015). Young Ruppia always maintains higher amounts of oxygen in its rhizosphere than Zostera because it leaks oxygen from both root tips and upper root sections. Zostera only loses oxygen from its root tips. Aside from more permeable root area, Ruppia also has larger biomass aboveground than Zostera that allows it to produce more oxygen via photosynthesis (Jovanovic et al., 2015). Oxygen leakage results in a less toxic rhizosphere because hydrogen sulfide is oxidized. Both Zostera and Ruppia are unable to maintain these protective oxic zones during nighttime when oxygen in the water column is 0-25% air saturation (Jovanovic et al., 2015). However, young Ruppia is better able to reestablish oxic zones than Zostera as oxygen concentrations increase. Ruppia is more protected against sulfide intrusion than Zostera. Ruppia’s ability to protect itself from sulfides partly explains why it is successful in recolonizing coastal shallow sediments that are low in oxygen and high in sulfides. As long as oxygen levels are not below a critical value, Ruppia has a competitive advantage over Zostera (Jovanovic et al., 2015). While Ruppia is more advantageous in these conditions, it is more vulnerable to damage by sulfide intrusion during times of hypoxia or anoxia due to its higher root permeability (Pedersen & Kristensen, 2015). Another advantage Ruppia has over Zostera is its tolerance to higher water-column nitrate concentrations from agricultural runoff and sewage effluent (Burkholder et al., 1994). Halodule also has high tolerances to large nitrate concentrations (Burkholder et al., 1994).
As nutrient loading continues in Chesapeake Bay and hypoxia remains prevalent, blue crabs may avoid these regions and migrate to shallower waters. Juveniles may continue to have slower feeding and molting rates. It remains uncertain why blue crab aerobic metabolism has been observed to both slow down and remain unchanged in hypoxic conditions, and why blue crabs do not always migrate during relaxation events to seek exposed benthic infauna. Ruppia has a competitive advantage over Zostera in hypoxic conditions and may serve as nursery habitat into the future.”
APPENDIX 4
Off-Bottom Culture Shows Faster Growth
Prudence Island Oyster Farm
P.O. Box 368
Warren, Rhode Island 02885

c: 401-245-8300                                 March 13, 1981        Home: 401-245-4444                                         
Mr. J. Clinton Hammond
106 Main Street
Chatham, MA 02633

Dear Mr. Hammond:

The attached report reveals publicly for the first time the new methods I have been developing in the effort to make string culture of oysters economically feasible.

As pointed out herein, the attempts to produce a good half-shell quality oyster by the string method have until now met with serious problems everywhere. Perhaps this is why some of my aquacultural friends look somewhat askance at string culture.

For two years, I have labored with new materials and many different ideas to prove this culture method is a viable one — knowing that the basic tenet of mid-water suspension was best if only a well-shaped oyster could be produced.

Here, in this Report, is depicted the Blount fixed spat oyster disc. I have never seen this technology nor have I heard of anything like it, and I believe it is shown here for the first time.

Further work must be done to render the process cost worthy and foolproof, but I firmly believe I am on the right track.

While I have applied for patents covering all phases of this process, I will gladly sell discs to anyone wishing to experiment further. String culture as I see it provides the most efficient growing space arrangement with the least amount of care and effort during the growing period. Meanwhile, I have in my Pond approximately 100,000 fixed spat oysters on sea scallop shells, which should be of marketable size during the Fall of 1981. These I believe will be the first production run of oysters grown by this method.

Very truly yours,
Luther Hammond Blount
Luther H. Blount 
LHB/gfr   
Rekeyed for The Sound School - 2/10/2016
Appendix 5

The Biology and Conservation of the Blue Crab, Callinectes sapidus Rathbun by Curtis L. Newcomber, Virginia Fisheries Laboratory, 1945
Review & Comments Timothy Visel

“Fluctuations in the abundance of crabs are of vital importance to the many persons engaged in the crab industry.  The causes that underlie unusually high and low levels of abundance are not well understood.”

In 1941, the Commission of Fisheries of Virginia established a crab sanctuary (a process also used in the oyster industry described as protected oyster spawning beds) area to protect egg-bearing blue crabs.

The area extended in a triangle from Cape Charles to Cape Henry to Hampton Roads – at the mouth of Chesapeake Bay.  It was thought at the time that habitats were static (did not move), but later acknowledged that habitat quality
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