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PostPosted: Fri Aug 05, 2016 6:29 am    Post subject: Blue Crabs & Salt Marshes & Habitat Succession #13-T Reply with quote

Blue Crabs, Salt Marshes and Habitat Succession #13
The Blue Crab Forum™ Environment and Conservation
July 10, 2016
A Capstone Proposal for FFA – Non Experimental SAE
Tim Visel
The Sound School Regional Vocational Aquaculture Center
60 South Water Street, New Haven, CT

{The views expressed here do not reflect the Citizens Advisory Committee nor Habitat Working Group of the EPA Long Island Sound Study. On February 16, 2016 I have asked resource management agencies to recognize Sapropel as a distinct subtidal habitat type. This is the viewpoint of Tim Visel}.

Note from Tim Visel

Reports – Vibrio and Sapropel (Acid Sulfate Soils)

When I was researching the Conowingo Dam and Florida Indian lagoon for case studies (2013) after reports of Indian River “Black Mayonnaise” or Conowingo Dam for sulfuric acid, I did not know that both could be very large investigations. I often write that Black Waters occurred a century ago preceding fish kills, but over the fourth of July weekend (2016) pictures of a large Black Water release from Lake Okeechobee Florida would be shown on national news outlets. Vibrio bacteria also was in the news- associated with some beaches over the upcoming Olympic site and in Texas.

The country providing the clearest easy to read public information about Sapropel (most soil scientists refer to it as Acid Sulfate Soil) and Black Water Fish Kills is by far Australia – my view.

The Australian Government Agency, the Department of the Environment, has issued two fact sheets: “About Acid Sulfate Soils” and “Blackwater Events and Water Quality Facts.” They are very clear and easy to understand habitat changes from these conditions.

For Chesapeake Bay blue crabbers who have noticed Sapropel (Acid Sulfate Soil) below the Conowingo Dam or anywhere in the Bay and had questions as to why some areas, seemed to dissolve metal blue crab traps, you can also see this chemical reaction as well. Acid Sulfate Soil (Sapropel) is oxidized rapidly to form sulfuric acid and water, just view the internet segment titled, “Violent Soil”. Here two soil scientists, Dr. Del Fanning and Dr. Martin Rabenhorst pull samples from the beach at Brian Point, in front of Hog Hole Creek, Maryland. I would describe this area as medium energy and subject to terrestrial organic matter inputs. They pull three samples; surface, but that sample produces none to little sulfuric acid, a deeper sample which produces a slight reaction and then a deep sample most likely sealed from oxygen and just two tablespoons produces a “flash” reaction (actually smokes) as sulfuric acid is violently formed - June 27, 2013. That is an experiment/trial with just a small beaker; imagine what happens after a heavy rain – sweeping thousands of tons of organic matter into coastal coves. It is an excellent clip and well deserves a look. If there were any questions about sulfate/sulfuric acid reactions in blue crab habitats, this video clip should answer them.

In a few days, soil scientists and soil science researchers from many countries will meet for the 8th International Acid Sulfate Soils Conference to be held in College Park, Maryland July 17 to July 23, hosted by the College of Agriculture and Natural Resources University of Maryland. The Draft Program is on the Internet, the conference looks excellent. That is at the center of the United States blue crab fishery.

I hope some Aquatic habitat ecologists and marine biologists will also attend – we need their habitat inputs and knowledge.

Tim Visel

The Connecticut Career and Technical Education System issues Agriculture/Aquaculture Performance Standards and Competencies. These performance standards are from the 2015 edition issued from the Connecticut State Dept of Education Academic Office. The Environment and Conservation post #13 (The Blue Crab Forum™ the following standards are referenced.

AE #4 Conversion of ammonia to nitrite and nitrite to nitrate
AE #6 Identify environmental factors – temperature, salinity, ammonia, nitrate, nitrite, dissolved oxygen and pH.
AE #9 Define non infectious diseases, including those from environmental conditions.
NRE #4 Identify ecosystems structure in terms of food web, biodiversity and carrying capacity.
#9 Describe process of ecological habitat succession.
#14 Identify water quality indicators pH, temperature nitrates, nitrites ammonia, dissolved oxygen and turbidity.

Capstone Questions

1) Can evidence be found for a cross discipline analysis of climate change impacts to habitat succession such as discussions between geologists, oceanographers, biologists, or the fields of chemistry – fishery science, soil science looking at sub tidal habitat change?

2) Many states contain historical records and archives that pertain to fisheries. Two fisheries that have perhaps the best historical habitat records are lobster and the oyster fisheries – when the oyster set of the century occurred here in 1898 the lobsters died off. How can increases in one fishery appear as another declines?

3) Do we have a good habitat history for Blue Crabs in Southern New England and could they become the best “sentinel” species for climate change?

4) Has the role of temperature and bacterial nitrogen generation been over looked in the process of defining marine habitat succession?

Students interested in this research area as a Capstone Project please see Tim Visel in the Aquaculture Office.


Blue Crabs Salt Marshes and Habitat Succession Questions

This is part of a three part report – readers should review part (1) Eelgrass Blue Crabs, lobsters and Vibrio Bacteria Environmental Conservation Blue Crab Forum™ #11 posted on April 28th 2016 on The Blue Crab Forum™ Environment and Conservation thread. Part 2 was posted June 2nd 2016 as EC #12 and now EC #13 – July 2016. This report focuses upon the role of bacteria as having a habitat succession function and may become the largest habitat quality indicator for inshore habitat quality in the decades to come.

Environment and Conservation – The Blue Crab Forum™ - Bacteria Nitrogen Series

I want to thank the Blue Crab Forum™ for allowing me to post in a new thread – Environment and Conservation and also Connecticut Fish Talk for reposting these reports. This is my thirteenth report about bacteria and nitrogen cycles. Coastal habitats once praised for valuable habitat services are impacted by bacteria and at times become nature’s killing fields, eliminating critical nursery and spawning grounds for many inshore fish and shellfish species. Coastal fishers often observe these events, mats of bottom bacteria, chocolate or purple waters, brown tides, (HABs) blue crab jubilees or just fish kills. Beyond these public events bacteria and nitrogen change the habitat qualities that we recognize today as “good” into something that is “bad” for inshore fish and shellfishing. Out of sight and rarely discussed, these conflicting bacteria strains have important implications for estuarine health and seafood production worldwide.

#13 Blue Crabs, Salt Marshes and Habitat Succession July 2016

#12 Blue Crabs and Marine Bacteria June 2016

#11 Eelgrass, Blue Crabs, lobsters and Vibrio Bacteria - March 2016

#10 Oxygen and Sulfur Reducing Bacteria Questions – Dec 17th 2015

#9 Nitrogen and Eelgrass Habitat Questions 11/18/2015

#8 Natural Nitrogen Bacteria Filter Systems 10/20/2015

#7 Salt Marshes a Climate Bacterial Battlefield 9/10/2015

#6 Bacteria Disease and Warm Water Concerns 7/23/2015

#5 Nitrogen, Inshore Habitats and Climate Change 1/12/2015

#4 Black Mayonnaise Impacts to Blue Crabs and Oysters 1972 to Present

#3 A Caution Regarding Black Mayonnaise Habitats 10/2/2014

#2 Black Mayonnaise, Leaves and Blue Crab Habitats 9/30/2014

#1 What About Sapropel and the Conowingo Dam? 9/29/14

Fishers should follow this bacterial conflict as more and more information comes in regarding habitat quality and important recreational fisheries such as striped bass, winter flounder and blue crabs or lobster habitats are subject to bacterial impacts. It is also important that shallow water fishers be aware that sulfur bacteria contain a series of antibiotic resistant strains first identified in “Contaminate Effects On Biota of the New York Bight“ by Joel, O’Connor, NOAA (1976). Soft organics with bacteria do pose risks to fishers and bathers – coastal bacteria benthic monitoring programs are needed. – My View.

On Land and Sea Habitats Succeed

Farmers for centuries have recorded what they see for habitat succession, a forest fire yields grasses soon after small cedar trees, then perhaps black locust (iron wood) hickory and then oaks. This is recognized as the law of habitat succession or sometimes the natural law of habitat succession – usually started by fire or floods or climate change factors themselves. We can also start or hold habitat succession by clearing forests and maintaining agriculture. Once such agriculture habitats are abandoned its easy to see this type of habitat succession over time. This terrestrial succession of plants is well recognized in the scientific literature.

In the marine field we also have reports from fishers, also for centuries but no marine habitat succession outlines? In particular the aspect of habitats themselves naturally changing over time is often “missing.” Several environmental organizations have recently stepped up and acknowledged the negative habitat impacts of Black Mayonnaise (Sapropel).

Harbor Watch an organization in Western CT (Earth Place) that for years monitored the Norwalk Harbor issued a caution in 2012 about dumping leaves into rivers and the negative impacts upon winter flounder habitats by “black mayonnaise.” (Richard Harris of Harbor Watch has an excellent paper titled “ Our Rivers Should Not Be Used As Dumping Grounds For Your Autumn Leaves Or For Other Yard Waste”). Save The Bay® an environmental organization that started in Rhode Island in 1970 one of the countries oldest civic environmental organizations has launched a special “Black Mayonnaise” environmental education program, mentioning negative impacts of grass clippings, leaf dumping and road organic run off. The Save The Bay® organization is currently targeting, little Narragansett Bay and the build up of Black Mayonnaise in its coastal habitats. These organizations should be commended for taking this issue on and reporting out to public and fishers. But we need many more to inform the public about Sapropel (Acid Sulfate Soil) and marine habitat succession (my view).

Several articles have been generated by Save the Bay® about Black Mayonnaise – more properly termed Sapropel. One of the civic groups that have sought out explanations for high sulfide levels in tidal water habitats (the upper salt ponds of the Narrow River) is the Narrow River Preservation Association (Rhode Island). A 2013 PowerPoint by Dr. Veronica Berounsky of the University of Rhode Island titled “What’s That Smell” is one of the best most “balanced” presentations about sulfate reduction I have found to date. But we need many more environmental organizations to step up and give the public a fair assessment that includes climate conditions impacting seafood habitat quality, most importantly how the sulfur cycle interacts with the nitrogen cycle. We need to recognize Sapropel for what it is a marine compost that “rots” even in low oxygen conditions. The study of sulfate reduction, Sapropel formation and the sulfides from them here been missing from many estuarine studies.

The overall critical research area is how temperature can alter the sulfur reducing bacterial process for nitrate, or ammonia altering habitat quality in both cold, the purging of sulfides and in heat ammonia generation. While the study of land composting has been well studied and even celebrated the aspect of “marine compost” that also included bio chemical features of salt marshes as languished for decades – except soil scientists who now term these soils as acid sulfate soils.

In oxygen sufficient waters this marine compost fulfills a very important filter system function for shallow water habitat (EC #8 Natural Nitrogen Bacteria Filter Systems 10/20/2015) and Richard Harris writes an article titled More Development of Norwalk Harbor – A Muddy Issue (The Norwalk Hour Monday, Oct 26, 1987) three decades ago about the value of these composting habitats to function as natural bacterial filter systems, a section is reprinted here.

“This natural system (mud flats) is valuable in providing treatment to sewage wasters oxygenated mud flats provide a substrate for very important aerobic (oxygen loving) bacteria.

Some of these bacteria decompose (oxidize) organic matter or sewage wastes in a process very similar to secondary treatment. Others (bacteria) oxidize ammonia to progressively less toxic products – nitrite and finally nitrate. This latter process is very important because a key problem in sewage treatment plants is the inability of most facilities to deal with nutrients in any fashion. The first form nitrogen to be released upon the decay of organic matter is ammonia, which is very toxic as little as .1ppm (parts per million) is lethal to some marine organism (for example a range of .4 to 2.3 parts per million will cause death to many crustaceans (blue crabs) helped by the large surface areas, mud flats begin the nitrification process. This natural ability to process some of the sewage in the harbor has been totally overlooked and has get to be quantified.”

And further (when the natural system are overwhelmed) blooms of algae described as a “Mass of plant cells dies off sinks to the bottom, consumes much of the available oxygen in the decay process and helps form the reducing – black mayonnaise – like blanket for the bottom. Again any natural mechanism that exists to help take up excessive sewage derived nutrients from the water ways should be evaluated and quantified, this has yet to be done” (1987).

In colder times sufficient oxygen allow these benefitcial bacteria to turn organic matter into less toxic compounds – ammonia to nitrate (as in many “closed” filter systems (EC #Cool. But in oxygen deficient waters these healthy mud flats transition into dangerous producers of toxic compounds from Sapropel. They also at times contain deadly Vibrio bacteria – even ancient sapropels are producing viable bacterial strains some that remain unclassified. (See Two Distinct Photobacterium Populations Thrive in Ancient Mediterranean Sapropels authors Jacqueline Suss et al, April 2008 Microbial Ecology Vol 55 #3 Pg 371-383).

At a recent EPA Long Island Sound meeting (Habitat and Stewardship Committee) I suggested that if I could (which I cannot) I would direct most of the EPA Estuary Program study funding to the study of Sapropel (Black Mayonnaise). It could provide many answers (I feel) to several habitat questions, from the bacterial formation of heavy metals (how lead got into lead pencils) the storage of sulfur cycle carbon, the purging of sulfides and ammonia, creating large swings of estuarine pH to the releasing of toxic aluminum and the “flash fires” of sulfuric acid washes after storms and now fish and shellfish diseases from toxic algal blooms. Sapropel acts to seal marine soils and suffocates shellfish populations, dredging may be the only reasonable way to elevate this condition at times very destructive deposit which is now linked to the Vibrio disease causing bacterial populations. Habitat wise we could learn a lot from this marine organic compost and the sulfur cycle it represents (my view). It is the very foundation of inshore habitat succession for our shellfisheries and possibly blue crabs.

As more information comes in about what climate warming can do to inshore habitats they fall into four basic categories. The southern high/energy salt marshes that capture organic matter from land, they might be very warm but not subjected to heavy loading of organic matter from land, the salt marshes filter it, southern areas with less salt marshes also warm but can go oxygen limited in poorly flushed areas such Indian River in Florida also Tampa Bay and the most famous low oxygen high sulfide events the blue crab Jubilees of Mobile Bay, areas that can obtain high volumes of organic matter with little to no salt marsh filtering such as small bays and coves. The fourth is the larger Bay/Sounds, which have marshes but subject to increased temperature swings or storm events Currituck Bay, Chesapeake Bay and our Long Island Sound at the edge of blue crab range. Here cold waters can reduce blue crab populations but cold does not adequately describe what actually happens in these shallow habitats the same habitats blue crabs call “home” when they are “warm.” It is these habitats that contain adjacent (leaves) forests and now subject to organic matter reduction as part of the sulfur cycle. In times of heat and slow currents or tides they often become “dead” bottoms to fish and shellfish.

When researchers describe often “Dead Zones” today they are at the mouths of rivers – it is the impact of organic matter being swept into coastal areas (mostly rivers but sometimes salt marshes) undergoing bacterial reduction. They frequently mention higher levels of sulfides. It is in part natural to have dead zones from these organic “composts” especially in high heat. That is the basis of the Saprobien system developed by Kolkwitz and Marsson in 1902 was directly connected to organic waste undergoing sulfate reduction and the excess sulfides when these deposits become “warm” they become “dead” to oxygen requiring life forms.

Can we contribute to the creation and duration of “Dead Zones” – most certainly but these events can be natural in times of high heat. Colder temperatures (or a lessening of organic matter) can reduce these dead zones they can wax and wane with temperature and why inshore fishers have different habitat perspectives, the shallow waters can change more quickly than the deeper and usually cooler offshore waters. What is a good habitat in cooler water can turn quickly negative in heat – the black water fish kills now associated with sulfide generation from sulfur (sulfate) reducing bacteria. When oxygen is low (high temperatures) bacterial decomposition can change from a short nitrogen nitrate recycling to a much more longer sulfate oxygen source for ammonia generation. This process occurs in shallow seas, salt marshes and on land with similar bacterial strains in peat/bogs. This chemical reduction is the process that creates the sulfate/bog iron mentioned in the Blue Crab forum post IMEP #57 on August 20, 2015 titled Climate Change – Case History for CT Halibut Fleet 1848-1881 Fishing, Eeling and Oystering Thread. Although much more research on this sulfate reduction is available from terrestrial studies it is a critical habitat quality factor for the blue crab – sulfide formation in subtidal habitats.

It is here that high seawater sulfate levels favor the sulfur reducing and Vibrio bacterial strains. Sulfate is plentiful in seawater and these sulfate reducing bacteria utilize sulfate as an oxygen source – they “breathe sulfate” as such will never face an oxygen shortage in Long Island Sound or in those areas to our south. Waksman (1936) earlier made the connection between microbial (bacterial reduction) and oxygen. His research was utilized in a 1954 report titled “Stratigraphic Distribution of Lipoid Substances in Cedar Creek Bay, Minnesota” by F. M. Swain and N. Prokopovich (Geological Society of America Bulletin in 1954, 65 #12 pages (183-198). Here Swain and Prokopovich define copropel as reworked organic matter – and urges the adoption of the term “Sapropel” for marine areas.

“The term is here suggested to replace guttja which has had somewhat vague applications – Sapropel is black, fine to coarse textured destritus formed by an aerobic bacterial decomposition of organic destritus in lakes and seas.”

Although the authors above did not consider temperature in the formation of Sapropel they did propose that lipoid concentration, the greasy sticky character of it was due to its source material before microbial decomposition. On page 191 under the discussion section is found this statement, (1954).

“The high Lipoid content just above the marl is probably due also in part to the relatively higher fat content of the original plankton rich source material. Considerable microbial activity occurs on the margin of bog lakes, where sedge growth is dense. This causes patches of Sapropel to form in the shallow near shore waters (most likely summer T. Visel) as well as in the hypolimnion zone (stagnant poorly mixed zone low in oxygen – T. Visel) of offshore parts of the lake.”

The Indian River (Florida) case history is one that offers explanations for habitat successional events attributed to the buildup of Sapropel in this lagoon-river system. It also has a personal connection as well; I spent a year here (1973-1974) studying oceanography at the Jensen Beach Campus of the Florida Institute of Technology. This school was located directly on the Indian River lagoon and an outstanding location to study oceanography (the campus was closed in 1986, but the space now holds a public park along with a children’s museum located in the remaining administration building). Here I had several oceanography classes and learned about the interactions of coastal waters. One of the things I learned was that Florida has groundwater with naturally high sulfide levels. Here sulfate digestion occurs naturally - aside from toxic sulfides, aluminate leachate is just as deadly to fish. Because of the iron and acidic waters, they commonly occur as “black” and are easily confused with tannins released as plant tissue decays such as the reports of “mahogany waters” after storms. It is the iron that causes Sapropel to be black as if the underside of stones sealed from oxygen picked up along a beach will show.

In general Sapropel remains poorly investigated and generally not recognized for having negative habitat impacts in the coastal zone. A Florida St. Johns River Water Management District study by Ashish et al June 2004 “Sediment Transport and Detrital Transfer Changes Related To Minimum Flows And Levels” zeros in an the confusion – on page 66 is found this statement.

“What emerges from a literature review is that the nature of such sediment remains rather poorly investigated in comparison with its emerging applied importance.

The black organic rich deposits have received a number of different names – a fact that possibly heightens the confusion. Locally these materials are called “muck” but in the literature similar deposits are term “guttja” a Swedish word – “Sapropel” (Sapros rotten, pel = mud) “ooze,” “black mud” or in recognition of its loose and fluid nature, “unconsolidated flocculent (UCF) material which may grade a deeper levels beneath the sediment surface to “consolidated flocculent” CF material.”

The Indian River is poorly flushed and like all such areas is subject to changes in temperature and energy. Periodic fish kills and algal blooms have targeted nitrogen pollution as the cause, but reports also indicate it suffers from the buildup of Sapropel (Black Mayonnaise) in some areas. It is the waxing and waning of Sapropel that can alter nitrogen/sulfur cycles in these warm waters. I feel that during the 1970s (when I fished the lagoon) Sapropel deposits were slight (I did see some, but only in a few areas) but in time have deepened? Most likely a good habitat history could be obtained from area fishers such as the habitat histories in our New England coves. In colder times, Long Island Sound did not contain deep Sapropel (Black Mayonnaise) deposits. In a 1970 study, “Sub Bottom Study of Long Island Sound,” Grim et al lamont Doherty Geological Observatory (printed in Geological Society of America Bulletin, March 1970, pg. 649-666) found that core studies yielded a Holocene silt” covered in most places by a few inches of black, gelatinous organic mud.” However, by the mid 1980s in shallow, poorly flushed habitats, Sapropel could now be measured in feet (Pattagansett River Study in 1990, NSA Abstract 1990, NSA meeting April 1-5, 1990, pg. 459). Winter Flounder and oyster farmers were the first ones to notice these substantial habitat changes and provided modest habitat histories because they fished the shallows. In time, black mayonnaise would bury oyster beds and suffocate clams. (See appendix #1).

Oyster growers and fishers usually report the first Sapropel accumulations as hard bottoms become soft. We have some excellent descriptions from the oyster industry in U.S. Fish Commission’s reports of the 1880s.

Speaking about the West Haven oyster fisheries in general, Ingersoll mentions the West River along New Haven’s westerly border.

“The small allotments in West River which they possess are nearly ruined by the drifting of sediment and the total product of the river last year would hardly exceed 500 bushels. One planter told me he had 12 acres in one lot in the harbor spoiled by becoming covered in mud” (pg. 66, The Fisher’s of the United States, Department of the Interior - Tenth Census of the United States, The Oyster Industry by Ernest Ingersoll, Washington GPO 1881).

Waters with vegetation, organic matter and sulfate can naturally have “black waters” and when oxygen sufficient support much fish life; However, when oxygen declines with the buildup of Sapropel, these sulfide waters quickly become deadly.

The blue crabbers in the lower Susquehanna River reported that metal crab traps dissolved after flood waters from the Conowingo Dam; organic matter (and perhaps sulfide waters) then fed into the sulfur cycle (sulfide digestion) as sulfuric acid washes occurred (see E/C #1 - What About Sapropel and the Conowingo Dam posted on September 29, 2014).

This was much the same condition described by Rhoads in a “1985” presentation {The Benthic Ecosystem then part of a NOAA – EPA workshop on Long Island Sound} who urged mapping of the Sapropels in shallow waters of Long Island Sound – as a measure of oxygen saturation availability. If Sapropel layers were increasing it would signify a shortage of oxygen, it they were lessening - an increase of oxygen. (EC 5– The Blue Crab Forum Jan. 2015 Was Black Mayonnaise Habitats (Sapropel) Missed?).

Anyone following habitat changes in the Indian River lagoon might find Dr. Rhoad’s (D. Rhoad, Department of Geology and Geographics, Yale University) 1985 paper titled, “The Benthic Ecosystem,” of interest. NOAA Estuary of the Month seminar series No. 3, Long Island Sound workshop issues.

Here Dr. Rhoad introduces the concept of sulfate reduction when oxygen is limited and sulfides associated with toxic sulfide “black water deaths” recorded a century ago.

Long Island Sound Seminars – Battelle contract E68-03-3319
May 10, 1985 – pg 56

“Underlying the dysaerobic and an aerobic water one typically finds organic black (ie sulfidic) muds that are termed Sapropels – these are rich in iron monosulfides, the physical properties of these muds are distinctive and the best description that I have heard of them is that they are like a “black mayonnaise.” Dr. Donald Rhoads – workshop participant, May 10, 1985 – Yale University of Dept of Geology.

Black water deaths were those caused by sawdust and chip wood waste in New England streams in hot, low flow conditions, which then entered estuaries (Black Mayonnaise, Leaves, and Blue Crab Habitats September 30, 2014, EC Post #2 - Blue Crab Forum) killing fish in shallow, poorly flushed coves. Some of the most detailed research about black waters occurred on the Androscoggin River in Maine in the 1940s. Here freshly painted white houses turned black from hydrogen sulfide releases (Defining a Nuisance: Wallace Scot McFarlane, Environmental History, Vol. 17 #2, pages 307-335, 2012).

The first black water nutrient (sulfide) acid poisoning report is attributed to Dr. A.P. Knight, professor of Animal Biology, Queens University, Kingston, Canada (1901). The deadly impact of sulfide toxicity from excess organic matter (in this case, sawdust) details the sulfide iron color of black water and its toxic impacts (Blue Crab Forum - IMEP #27, September 30, 2014, Fishing, Eeling and Oystering Thread, The Western Connecticut Habitat Failure for Blue Crabs).

This is the account of Dr. A.P. Knight’s experiment in the 1900-1901

“When sawdust was allowed to lie in still water, or in very slowly running water, the most disastrous effects, followed the immersion of different animals in the poisonous mixture. Not merely did adult fish die in it, but fish eggs, fry, aquatic worms, small arthropods, animalcules and water plants. Nor was the cause of death due to suffocation from lack of oxygen because when air was made to bubble rapidly through the solution the final results were the same, the only difference being that death was somewhat delayed. No one could paint too vividly the deadly effects of this solution. Adult fish died in two or three minutes, fish eggs in a few hours, fry and minnows in from ten to fifteen minutes, aquatic worms and insects, eight to twenty-four hours- aquatic plants in a few days. Every living thing died in it and if one were to judge of the effects by laboratory experiments above then the prohibitory legislation need no better defense” (referring to Canadian statues forbidding the throwing of sawdust into streams).” The following year European researchers would publish the Saprobien System – water quality classifications based on organic matter pollution (Kolkwitz – Marson 1902).

How do blue crabs react to the formation of black water filled with sulfides? They flee from it as they do in blue crab “jubilees” in bay and coves or from rivers such as the Housatonic River in July 2011. The sulfide rich and toxic black waters also developed around river paper and pulp mills (see Paul Galtsoff and York River Virginia Oyster Investigations of 1935-1937, Appendix #2, June 11, 2015, IMEP# 51-B, The Cycle of Eelgrass and Fish Habitats - 1890-1990). However, any organic matter that is natural or the result of leaf dumping can create toxic waters. The introduction of organic matter is often more damaging than nitrogen compounds in liquids. Nitrogen-locked organic matter supports sulfate digestion (the same method used in the formation of paper) and the formation of toxic hydrogen sulfides in the same area as key habitats for many species. Rivers that undergo natural sulfate reduction in this fishery’s history literature are often referred to as “Black Water.” They also often have a high tannin signature from the digestion of organic matter (IMEP #27, September 2014, The Blue Crab Forum, The Role of Tannin - Sapropel Cycle in Habitats).

The study of peats offers a basis to look at Sapropel in shallow marine waters having a defined bacteria – habitat quality connection. (See EC #12 The Blue Crab Forum™ on June 2nd 2016).

Shallow Water Habitats

What many blue crabbers experience is Sapropel formation – before it becomes peat and many researchers going back into geological time have established defined climate patterns for the appearance of Sapropel (Black Sea Sapropel and sulfide generation). Sulfide generation and the toxic impacts of it are largely overlooked in recent estuarine habitat studies.

Many field studies mention Sapropel (locally called Black Mayonnaise) by other terms acid sulfate soil and distinguish the end result of stripped carbon chains – termed carbon sequestration – but do not mention the sulfur reduction process that makes this carbon storage possible. This leaves many questions as to the source of sulfur compounds in heat and habitat impacts from bacteria.

But what was the source of all this organic carbon locked up in organic matter? Plant Life Research by the Office of Energy Research – United States Department of Energy looked into this carbon flux in 1980. A workshop conducted at Woods Hole Massachusetts September 21-25, 1980 (Report Conference 8009140 UC-11 April 1981 – United States Department of Energy 400 pages) looked at flux of Organic Carbon by Rivers To The Oceans. The final report was prepared by the Committee On Flux Of Organic Carbon To The Ocean – Division of Biological Sciences National Research Council of the National Research Council – contract # DEFG-0180- EV10335. The introduction to this large report describes this organic carbon input as a “flux” and although not exactly the same response it is similar to the organic input foundation of the 1909 Saprobien System (European system based upon organic matter pollution in low flow rivers) of Europe.

The size of this carbon locked up in organic matter is detailed in the introduction on page 1 – my comments in brackets { }.

“The transfer or organic carbon from land to the ocean represents a flux {input T. Visel} of potentially storable carbon, reversible over many thousands, if not millions of years. This transport of organic carbon {organic matter mostly leaves – T. Visel} to the oceans by rivers has received only super facial attention to date, but it is important of global carbon cycling is to be understood. The state of knowledge about the role of rivers in the transport, storage, and oxidation of carbon is the subject of this report, which summarizes a workshop held at Woods Hole, Massachusetts in September 1980.”

In the section titled “The Future of River Carbon exported to the Marine Environment” – the report mentions the uncertainly of the amount but storage of terrestrial carbon in nearshore sediment was well established. Evidence of this storage was that the refractory organic carbon stored in many estuarine regions is soil – derived and found in data from studies in the Baltic Sea and Long Island Sound. In both of these estuaries the dominate of 14C – old carbon in the sediments prior to the industrial revolution identifies a predominant “soil component in the stored carbon.”

But the storage of carbon chains stripped of usable compounds generates some of the most toxic sea life conditions. Carbon sequestration has a biological price and in hot weather that price can be very high. In the end the final stripping of carbon chains are those bacteria classified as the methogens and the production of methane in a process that leaves bitumen the foundation of oil and coal (this is how sulfur is in coal deposits).

That is why I raised caution about the Conowingo Dam in my first Environmental and Conservation Post, dated 9/14/2014. The organic matter necessary to produce the stored carbon is a by product of the deadly sulfur cycle, two current case history examples Clinton Harbor Connecticut and Green Harbor (Mass). After heavy rains organic matter is swept over the Conowingo Dam that could feed the sulfate reducing bacteria – below in tidal waters resulting in sulfate organic matter reduction for years in a “slow” nitrogen release pathway. Once this organic matter is re-exposed to oxygen it can produce a sulfur acidic wash – just as terrestrial farmers experienced and detailed a century ago. (IMEP #26 CT Rivers Lead Sapropel Production 1850-1885). Coastal dams do act to accumulate large organics deposits and once flushed down stream feed into the sulfur cycle, sometimes for years, perhaps decades. Some crabbers from the Chesapeake Bay region claim that some blue crab habitats have yet to recover from Hurricane Agnes in 1972. (The Effects of Hurricane Agnes on the Environment and Organisms of Chesapeake Bay, US Army Corps of Engineers – Coastal Zone Information Center – GPO Washington DC – Jan 1973 Contract DACW 61-73-9348). This 1973 report reveals the extent of the organics swept downstream from Agnes.

“Aside from “Chocolate Waters” (pg 26) it was estimated that the amount of sediment carried down stream was that of the flood of 1889. Chocolate waters historically that have carried huge amounts of organic material – referred to as “bio stimulation” but noted documentation of “dissolved oxygen following Agnes will be useful not only in predicting the effects of future floods but also in predicting the effects of future inputs of nutrients as result of man’s activities” pg 71.

For years fishers may observe these habitat succession events set into motion by these habitat reversals. In the marine environment we don’t have forest fires instead we have hurricanes and a “flood” of organic matter that follows. In these areas deep core samples should leave a history of these organic flood events, which may take decades for sulfur bacteria to consume. Organic enrichment and the creation of “black waters” can even come from green leaves, see the excellent account of the Atchafalaya BasinKeeper® Hurricane Gustaf fish kill in 2008 (the green manure effect).

Marine Bacteria are Part of Habitat Succession

Nitrogen fixing bacteria are those that in the presence of oxygen form nitrates which then can be utilized by plants. But those bacteria that are saprophytic on organic matter in the soil and release nitrogen do it in another pathway – one associated without oxygen – deep in terrestrial soils but also in marine organic deposits. The initial product is ammonia as these are the “nitrifying” bacteria. If there is no or low oxygen available the ammonia is not oxidized to nitrites, and then further to nitrates. This reduction process stops at the ammonia level. Ammonia levels over time tend to rise in these warm oxygen poor waters. This process is termed denitrification but without oxygen is “stalled” and bacterial conversion to nitrites and nitrates cannot proceed any further (see EC#8 Natures Natural Filter Systems - The Blue Crab Forum™). Inshore waters are then bathed in higher amounts of ammonia – food for the algal species that can utilize it and that mostly is the Harmful Algal Blooms frequently called “HABS.” Most often these algal blooms are brown in color. The warm (often shallow) water is frequently the trigger for opportunistic species that need high ammonia levels. Some waters may appear “pink” or white but this is from purple sulfur reducing bacteria that from time to time color waters. (See pg 208 Climate Change and Coastal Ecosystems 2014 Robert J. Livingston) and Ammonia with depth may increase dramatically during sulfur reduction (see Narrow River Overturn of 2007 – Berounsky, Dec 2012). In colder temperatures bacterial reduction favors the production of nitrate and algal strains such as Chlorella in Long Island Sound in the 1950s. In the 1890s it was just the opposite the production of Ammonia and hydrogen sulfide then increased – the smell of rotten eggs and “black waters.”

In the late 1890’s, researchers noted the growing absence of nitrate (the “good” nitrogen) needed for nutritious algae and conducted experiments actually adding it to bays and coves. The absence of nitrogen-nitrate was most likely the result of the transition in the bacterial populations. Those in hot weather and low oxygen areas turned to nitrate as an oxygen source first to survive, while sulfur-reducing bacteria had plenty of sulfate (EC #8 Natural Nitrogen Bacteria Filter Systems - October 30, 2015). This would drive nitrate to very low levels, “starving” the bacterial populations in hot weather (the same as some filter systems in aquaculture) while background ammonia levels likely would rise.

The 1898 coastal history of the Narragansett Bay’s 1898 red tide bloom and the strong smell of sulfides is consistent with many other accounts (IMEP# 27, Blue Crab Forum, September 2014, Fishing, Eeling and Oystering Thread) details this “plague” as it was called then. When nitrate was exhausted, the algal strains that needed it also were replaced by the blue-green and “brown tide” strains that feast upon a growing level of ammonia. These algae strains are not food for shellfish - which are surrounded often by toxic residues (sulfides and neurotoxins) causing them to perish (this process could in fact be duplicated on a much smaller scale in habitat studies) - toxicology of habitats. The role of ammonia toxicity has been complicated because until very recently, it was established procedure to wash ammonia from samples before testing them for toxicological studies (EPA 600/ 12-94025, June 1994, Methods for Assessing the Toxicity of Sediment Associated Contaminants with Estuarine and Marine Amphipods - Errata, Pages 80-82, Sections 11.4, 5-, Effects of Sediment Associated Ammonia)

This procedure was described in a December 21, 1993 guidance memorandum issued by the U.S. EPA Office of Wetlands, Oceans, and Watersheds and the U.S. EPA Office of Science and Technology contains this section,

“Whenever chemical evidence of ammonia is present, toxicologically important levels and ammonia is not a contaminant of concern. The laboratory analyst should reduce ammonia in the sediment interstitial water to species in specific no-effect concentrations. Ammonia levels in the interstitial water can be reduced sufficiently aerating the sample and replacing two volumes of water per day.”

That it why some of the first HAB occurrences happen in shallow water with deepening Sapropel deposits. In heat and low flushing ammonia levels can now build – in fact a large amount of the ammonia can be traced to bacterial reduction of leaves (organic matter) and not from human sources. Oak trees in fact can be a large source of nitrogen by way of this bacterial reduction pathway - leaves as a “food” source for sulfate reducing bacteria. On page 266 of An Introduction To Botany – Arthur W. Haupt (1946) describes a nitrifying bacterial pathway as “Nitrifying bacteria also live in the soil (terrestrial) and, like those just mentioned, form nitrates, but in a different way the decomposition of organic matter (Sapropel in marine soils – T. Visel) by the bacteria of decay yields ammonia.” It is the ammonia production from Sapropel that is key to fully understanding this habitat impact as algal blooms grow so dense as to color the water. (See IMEP #27 September 2014 – The Blue Crab Forum Fishing, Eeeling and Oystering thread).

In the 1980s Sapropel (Black Mayonnaise) (acid sulfate soil) organic deposits grew deeper on shallow bay bottoms in New England and quickly in those areas with sluggish tides or restricted circulation. As the heat continued to build it is suspected that Sapropel deposits shed huge amounts of ammonia and in some areas supported toxic algal blooms (those species that could utilize ammonia and not nitrate forms). In the heat, the algae that needed nitrate died off (starved) while those that could use sulfate now thrived and became dense cultures - in some regions waters now turned brown and by products of these warm water algal strains are frequently toxic themselves. In a short time these bays became sulfur killing zones as sulfur reducing bacterial action increased. Bay scallopers and shellfishers are perhaps the group most impacted by these blooms – as these fisheries like Sapropel exist in the shallows and in water subject to the fastest heating from climate cycles. Some of these algal strains such as Cyanobacteria named by Dr. Field in 1901 produce toxins themselves in hot weather.

For Long Island Sound during extreme cold periods nitrates were abundant, in heat higher ammonia levels are recorded. In western Long Island Sound adjacent to organic matter deposits are recorded some very high ammonia levels – especially in areas with sluggish tides often described as flushing (these higher ammonia levels are associated with Western Long Island Sound).

Sapropel “Black Mayonnaise” (acid sulfate soil) is a concern in many coastal areas – as the sulfate bacterial reduction process dominates, in these areas ammonia levels can soar. While most recent studies mention human nitrogen inputs very few explain that perhaps the largest source of ammonia in warm weather is not us but bacteria living in Sapropel organic matter. In areas of restricted tides ammonia can slosh back and fourth for days as ammonia levels rise from organic digestion. Areas that have given us a clue as what can happen in areas of high organics and shallow waters is the Long Island, New York duck farm industry. Here layers of Sapropel on the bottom still decades later still shed high levels of ammonia and sulfides dredging is the only option for these habitats – as storms and cold temperatures can break the sulfate/ammonia cycles but can take a long time to do so (see Meeting House Creek Dredging Feasibility Study and Plan August 2010 or page 4 of the Suffolk County New York, Army Corps of Engineers Report of February 2009) – as this section below describes,

“The increase and decomposition of organic matter, derived directly from the duck waste as well as the increase in algal biomass, contributed to anaerobic benthic conditions impacting flora, such as submerged aquatic vegetation; and fauna, such as benthic invertebrates and foraminifera. Dense algal blooms prevented light penetration to the benthos, causing plant decay and additional organic deposits (O’Connor 1972). These organic rich sediments, often several feet deep, became soupy, black, clayey silt that had a rich odor of hydrogen sulfide, so potent that homeowners adjacent to Moriches and Great South Bays complained that the paint on their homes was being discolored (Nichols 1964; O’Connor 1972). Ecological degradation that was associated with the accumulation of nutrients throughout the estuarine bays continued throughout the history of the duck industry, and was heightened when the Moriches Inlet was temporarily closed (Nichols 1964; Lively et al. 1983) in the early 1950s.”

In many areas dredging is the only way to break this sulfur cycle and study of Sapropel (Black Mayonnaise) had ceased in the 1960s, as storm intensity increased and higher oxygen levels returned to Long Island Sound.

Habitat Succession Can Be Bad For Some Species We Value

The concept of toxic or toxic producing soft bottom habitats has raised a dilemma in seems in the environmental community – for so long promoted the importance of soft bottom habitats – therefore the study of Sapropel (often known by fishers as black mayonnaise) has stalled, or in many states ceased. For decades the environmental policy was non disturbance or nearshore habitats (any disturbance deemed as a negative or unnatural event) when it was energy storms, wind, waves or tides that first created them. Add higher temperatures and these soft bottom habitats are the first ones to become toxic – deadly and poisonous – a large digression from current environmental policies about working the bottom or cultivating marine soils.

The current descriptions of soft bottoms communities themselves often have a bias of the past regulatory mindset – the studies usually emphasizes the negative impact of human inputs but fails to cover any positive attributes – leaving a bias as though the science of agriculture dealt only with the study of weeds, not soils (my view). In many cases we have given the natural world a “free ride” in the literature for negative habitat attributes and nearly always our associated habitat modification or mitigation as negative, not positive (i.e. forest fires). Nearly all estuarine sub tidal communities have a built in cool/oxygen bias describing those habitats as diverse or enriched in cold oxygen rich water but make little mention of them in hot or warm/sulfur habitats. The king pins for soft bottom estuarine study can be defined in four general areas or categories, baseline habitat stability, (habitat services) biologically diversity (richness), habitat disturbance (dredging) and eutrophication, (pollution). The latter often is the most biased, not so much its attention to a lack of oxygen but often fails to mention an increase in sulfur? In some soft bottom communities descriptions of the words Sapropel sulfate reduction or sulfides are not mentioned at all. The term Sapropel largely dropped from the research community in the 1950s as the NAO weather pattern turned negative, or colder in New England. Oxygen levels were not viewed as a problematic as inshore habitats had high oxygen saturation levels. In cold water it was natural to have high oxygen saturation levels. In cold water bacterial species reduced organic matter and in the process released “nitrate,” the good nutrient for nutritious algae that fed oysters and clams. When temperatures rose in the 1980s, bacteria strains changed as oxygen levels dropped and now sulfate reducers took over and instead of “nitrate,” the good nitrogen compound now became ammonia, the toxic nitrogen compound, which is now fuels the brown algae and even more toxic blue-green algae strains called, cyanobacteria.

The conversion of bottom bacterial strains largely went unnoticed a century ago, but not by shore fishers. When it comes to temperature induced habitat changes, they see the habitat change results before anyone else. The bottom changed and the smell of sulfides increased. The “rotten egg” smell is mentioned so many times with the black water fish kills almost always in times of “heat” in historical fisheries literature.

By the late 1930s, the oxygen-nitrate and sulfur ammonia pathways were well known in the scientific literature. Edward Deevey did a great job of bringing these pathways forward as nature’s natural filtering capacity as they were important to coastal ecology, but he as many researchers during this period, drew observations during a period of cold temperatures and frequent storms. A climate bias contained within his significant “In Defense of Mud” article authored in 1970 was during the end of the negative NAO cycle in the Western Atlantic. I don’t think many researchers realized what an increase in temperature and decrease in energy would have on estuarine habitats, except those who fished in them. They have seen the “black bottoms,” experienced the rotten egg smells and black waters long before the natural composting high heat sulfate reduction/ammonia generation was recognized. After all, the first blue crab jubilees happened before dense populations occurred on the coast. Until recently, the biting insects, lack of shade and storm damage made those places dangerous to inhabit. Native Americans arrived along the Connecticut shore in late August during a dry time, burned local marshes (perhaps insect control) and harvested seafood in the so-called late season, “Indian Summer.” These summer camps were abandoned by December far before the February gales that could bring very heavy snows.

During the winter cold water, oxygen bacterial reduction would produce nitrate for spring algal blooms - “the good nitrogen” for nutritious algae many shellfish biologists would describe in the 1960s. But in the heat, the sulfate/ammonia pathway dominates, oxygen and nitrate become short or “limited” and the sulfate ammonia pathway builds into its compost Sapropel - black mayonnaise.

The aspect of natural would soon come to mean different things in terms of natural resource use.

A Closer Look At Salt Marshes

“Save The Marshes” became an organizing force in Connecticut’s Environmental early public policy led by Ann Conover of Guilford and Lyle M. Thorpe of the then Connecticut State Board of Fisheries and Game.

Salt marshes then the 1960s were looked at as lost economic opportunities, potential house lots (after filling) and aptly described in a letter written by Arroll L. Lamson, Chief Game Division to Paul S. Galtsoff U.S. Fish and Wildlife Service, at the time “Here in Connecticut we are fighting the seemingly loosing battle of saving our tidal wetlands.”

Director Lamson asked the US Fish and Wildlife Service, Paul Galtsoff shellfish researcher to meet with Connecticut officials but in this colder period Paul Galtsoff and meeting transcripts described the significance of salt marshes to winter flounder (a complete transcript is available from The Sound School) as to the climate period then favored them. They were in the salt marshes then in large amounts (creeks salt ponds and coves) and therefore of habitat value to fishers. If a similar study was conducted some 50 years later, salt marshes held at times incredible numbers of blue crabs. In the 1950s and 1960s blue crabs were not abundant but with the cold their habitat quality had succeeded (declined) but winter flounder benefited from higher oxygen, cooler waters and an energized marine soils washed of sulfide in which winter flounder now thrived.

Environmentalists such as Ann Conover of the Guilford Conservation Commission (Connecticut) in the late 1960s would change the public policies against the concept that salt mashes were disease causing swamps but instead valuable shore habitats that should be saved for many species (which they should be of course). In the colder 1950s and 1960s oxygen requiring life were abundant in those salt marshes. The black water sulfide fish kills of the 1890s or Malaria outbreaks of 1912 had been exclipsed by a negative NAO climate pattern.

But the environmental groups in the 1960s and 1970s saw salt marshes in a very different way than coastal residents of the 1890s-1910s (an excellent account of changed public policies can be found in a paper titled, “The Full Circle: A Historical Context for Urban Salt Marsh Restoration” written by David G. Casagrande, Center for Coastal and Watershed Systems, Yale School of Forestry and Environmental Studies). As the Great Heat in the 1880-1920 period showed in New England, climate warming brought swarms of mosquitoes from warm, salt marshes and mosquito disease soon followed. The public viewpoint of them changed (even those in the farming community) saw salt hay crops falter as they sunk in places creating hot, sulfide pools in summer and mosquito breeding habitats. Did the Connecticut Conservation Association Action Letter and a special report, “The Guilford Marshes,” mention that Connecticut in 1895 (in the midst of the killer heat waves the 1890s) “had declared all marshes a threat to human health” (Casagrande 1998). Later, Greenwich and the State Health Departments issued orders to fill in any marsh able to hold mosquito pools (habitats) during the Greenwich Malaria outbreak of 1912-1913. The effort to save the marshes in a much colder NAO climate period had very much changed observation and public perceptions, but the disease causing threat to human health lagged far beyond the change in climate periods. Even into the 1960s the memory of salt marsh Malaria dread could still be found. To understand this viewpoint it is important to review the context in which they were framed.

In the 1890s, coastal communities provided shore visitors (opportunities for city dwellers) to escape these killer heat waves (the rise of shore communities), but was now at risk from mosquitoes.

This change in public opinion at the time (and no doubt had an economic edge for coastal areas) towards salt marshes as a dreaded habitat of disease and source of financial loss. This replaced an earlier view for the agricultural value of salt hay. This is excerpt of the 1908 Herring River “Dike” Testimony that reveals what many coastal towns faced with salt marshes during the “Great Heat” 1880-1920 in New England: Pg. 34, Herring River Wellfleet Mass Hearing Transcripts, June 10, 1908

“The Mosquito Question”

“While the mosquito question is herein treated largely through its relation to the matter of summer visitors, it is obvious that it is of importance wholly aside from that as it affects the comfort and to some extent the health and prosperity of all permanent inhabitants of Wellfleet.

The condition of the marshes above described including the formation and retention of stagnant pools affords opportunity unexampled for breeding mosquitoes that in numbers, size and voracity equal anything experienced in New Jersey, the tundras of Alaska, or other places on this continent that have been inflicted with the pest. The particular vicinity in question, that is to say within practically the whole limits of the town of Wellfleet, these insects are throughout the summer an intolerable nuisance and curse to all and those who had had occasion to visit, live, work or play within the radius of their accustomed activities.”

But in heat these salt marshes were also the source of disease, as they had been for hundreds of years – as such habitat successional events a part of Connecticut’s “environmental” climate history (see IMEP #16, 1Cool with an extensive educational and political influence civic groups (such as those started by Ann Conover) became to realize that coastal development could be controlled by means much stronger than previous conservation, policies, but regulatory environmental protection.

The habitat succession attributes (in the warm periods a potential source of disease) in the coming years were deleted from salt marsh studies (an obvious public detraction from the valuable habitat message) as a first attempt to glean history from a public policy message and it as a public “means” provided and “ends” that clearly protected the marshes. One could imagine the lack of public policy makers support with a concept “Help Us Save The Marshes – linked to Malaria” versus “Help Us Save Us The Marshes – linked to winter flounder” as public policy soon guided research its easy to see how this negative high heat salt marsh habitat succession attributes could be quickly “forgotten.” As this conservation message contained an agenda of environmental protection far beyond conservation and that in time could discourage any resource use – my view.

The public is best served (my view) with full knowledge and explanations of marine habitat succession and its importance to better understanding our involvement in fisheries. In actual publications, the negative side of salt marshes in hot or warm periods just did not meet public policy objectives – “So it was forgotten.” This environmental amnesia would be repeated with eelgrass publications and now perhaps with blue carbon. The pattern of ignoring marine habitat succession events however appears to have started with the salt marshes. (IMEP #16 Climate Change and Public Opinion was first issued in 2008 for the EPA – Habitat Restoration Committee).

We may need a legislative initiative to mandate a complete habitat history review – as the Sapropel (Black Mayonnaise) case history now illustrates (my view). We just should not forget large segments of environmental habitat history because it does not support current public policy agendas – the information on habitat succession should be available to everyone – my view.

I welcome comments/suggestions and respond to all emails at tim.visel@nhboe.net

Appendix #1

Reduced Oyster Recruitment in a River With Restricted Tidal Flushing

Timothy C. Visel
Sea Grant Marine Advisory Program
The University of Connecticut at Avery Point, Groton, CT 06340

Robert E. DeGoursey, Marine Sciences Institute
The University of Connecticut at Avery Point, Groton, CT 06340

Peter J. Auster, National Undersea Research Center
The University of Connecticut at Avery Point, Groton, CT 06340

The Pataguanset River in East Lyme, Connecticut, historically supported a natural oyster bed that has recently declined in productivity. A series of surveys of the river (1985-1988) identified one natural bed comprised of large adult oysters (10 cm to 18.7 cm shell ht.) and few juveniles (<4.6 cm shell ht). The reintroduction of an oyster fishery would quickly deplete this resource without substantial recruitment of seed oysters. Three attempts to restore the oyster setting capacity of the bed by cultch planting and shell base cultivation were unsuccessful. No new seed oysters were observed. Direct underwater observations confirmed heavy silting of newly planted shell cultch, preventing the setting of oysters. Further examination of the lower Pataguanset River near a railroad causeway revealed a historic oyster bed buried under approximately 1 meter of organic sediment. The construction of the railroad causeway reduced the overall width of the river from over 1,000 meters to approximately 15 meters. Effects of the causeway including increased siltation and reduced salinities due to restricted tidal flushing, have negatively impacted the population dynamics of the natural beds. Ideally, tidal flow should be restored. However, management under the current hydrologic regime should include hydraulic cultivation and intensive shell base maintenance in order to enhance oyster productivity.

National Shellfisheries Association, Williamburg, Virginia Abstracts,1990 Annual Meeting, April 5, 1990 – pg 459.

Appendix #2

The Day, New London, Conn., Wednesday, June 12, 1985

Specialist warns agency of ‘black mayonnaise’ threat

By William Hanrahan
Day Staff Writer

GROTON – they call it black mayonnaise – it’s the murk and muck, sometimes several feet deep, that collects on river bottoms. It’s also the stuff stifling the area’s oyster crops, according to an expert.

Addressing the town’s Shellfish Commission Tuesday night, Timothy c. Visel, a marine resource specialist for the University of Connecticut, said the build-up of debris in shellfish area’s can weaken or eliminate growth.

Working in waters off Old Saybrook, Clinton and Madison, Visel said production of oysters there has more than quadrupled thanks to clean-up efforts during the past three years.

“There seems to be a trend that our rivers are filling up with black mayonnaise,” he said. “We have seen a dramatic increase in river life as the dead stuff is removed.”

The accumulation of debris occurs in waters with poor circulation. “We get so many nutrients going into these sluggish coves without a lot of circulation,” Visel said. “This causes a build-up and no oxygen gets down in the water.”

Visel said removing debris not only enhances oyster growth, but has increased the presence of a number of other fish, including flounder.

Visel said Connecticut used to be a leader in oystering about 100 years ago, with local areas such as the Poquonnock River as prominent beds. More than 100 oyster companies on Cape Cod used to rely on seed oysters from Connecticut which were brought there to mature.

Production dwindled to almost nothing as waters became polluted, he said. A clean water act in the late 1960’s helped rekindle the industry during the 1970’s, but things are still not what they used to be.

Removing black mayonnaise helps oysters and other life forms grow and even cultivate in areas previously devoid of life.

“About 1500 bushels came out of Old Saybrook last year and no shells were put in the water,” he said.
Visel said areas where mud is a problem often smell bad or show a white, milky substance floating on the water. Commission members said they had seen signs of this in town waters.

Debris can be removed from river and cove bottoms with oyster dredges, Visel said. By stirring up the mud at high tide, the debris is able to flow out of the area when the tide changes.

Debris can consist of decaying leaves, sticks, logs, garbage and nutrients which build up in the water. Visel said water jets also have been effective in removing mud

The commission plans to study the information presented by Visel before considering possible action.

Appendix 3

Shellfish Closures in Massachusetts: Status and Options

Edited by Alan W. White and Lee Anne Campbell

Woods Hole Oceanographic Institution Woods Hole, Massachusetts 02543
September 1989

Technical Report

Robert A. Duncanson
Water Quality
Laboratory Town of Chatham
Chatham, MA 02633
Dale L. Saad
Town of Barnstable Health Department
Hyannis, MA 02601 (1989)

The use of bacterial species as indicators of the sanitary quality of water had its origins in the early part of this century. The indicator concept was begun as a protective measure for potable water supplies in response to widespread outbreaks of waterborne diseases such as typhoid and cholera. The use of bacterial indicators in the shellfish arena began in the 1920s following several outbreaks of typhoid linked to oysters. Since the introduction of bacterial standards for both shellfish growing waters and market samples, the incidence of shellfish-borne disease has declined. The question thus becomes why should consideration be given to a change in the indicator system which appears to have been working adequately for over 60 years?

The answer to the question posed above is multifaceted. Although the incidence of classical shellf
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