CTFishTalk.com: Special Report #3- Rhode Island's Blue Crab Capital T-Visel - Connecticut Saltwater Reports ( CT Saltwater Reports ) - A Community Built for Connecticut Fisherman.

BlueChip

The Search for Megalops 2010-2015
“You Don’t Need to be a Scientist to Report”
Special Report #3
Rhode Island’s Blue Crab Capital
Tim Visel - The Sound School - October 2015

Rhode Island’s Blue Crab Capital
The Search for Megalops

So many Rhode Island and Connecticut Blue Crabbers have contacted me about the drop in crabs this summer and questions about blue crab cycles I have included a special section about Rhode Island’s Pt Judith Salt Pond. Here is more likely one of the best areas to research this question and detail a long term habitat and fisheries history for blue crabs in New England. Several Rhode Island crabbers have asked about blue crab population cycles I hope they find this section of interest.

Pt. Judith salt pond as many New England coves and bays gave us a view as to what climate cycles can do to inshore fisheries – both positive and negative with our own “value” bias. I believe that after 1998 blue crabbing generally improved in Pt Judith Pond and after the past cold winters declined as in other New England crabbing locations. (Rhode Island officials are looking into this now).

In the middle 1970s while attending the University of Rhode Island I learned that at one time Pt Judith Salt Pond was called “Rhode Islands Blue Crab Capital” but as the climate cooled during a negative NAO cycle – blue crabs faded and declined after the 1940s. The current positive NAO - 1974 to 2012 most likely saw a gradual improvement in blue crabbing in Point Judith Salt Pond as we recently experienced in CT.

One of the areas I wanted to look at was the Pettaquamscutt Salt Ponds – Lake shores area. In this area (in the ponds) I observed intense oyster setting in the middle 1970s and was perhaps a good spot for blue crab megalops. The Rhode Island US Fish and Wildlife Service is sampling in the Narrow River and agreed to share Blue Crab data. Many thanks to Helen Day of the Dept of Natural Resources Science (URI) for cooperating with this request. A few years back Katheen Castro and Barbara Somers of my old fisheries dept (URI) were looking into the blue crab population increase as well.

If any Pt Judith Salt Pond crabbers would like to comment please drop me an email at tim.visel@new-haven.k12.ct.us.

I would like to thank both Dr. P.J. Capelotti and Dr. C. Leah Devlin for reprint/use permission of their paper titled, Proximity to Seacoast: G.W. Field and the Marine Laboratory at Point Judith Pond, Rhode Island, 1896-1900. As a three time University of Rhode Island graduate, reading about the history development of the University marine programs was fascinating. It was very helpful in researching this fisheries habitat history aspect of Point Judith Pond. I am certain that turn of the century local newspaper articles will detail many of the fisheries here in this area as well as archived notes of Dr. Field who headed this first marine laboratory. Dr. George Field went on to become one of the early pioneers of aquaculture and to head to Massachusetts Fishery and Game department and then President of the organization now known as the National Shellfish Association. A great write up of his biography is on Wikipedia.

It is my hope that perhaps some URI students or some Rhode Island blue crabbers might take some time to put together a more complete habitat history for Point Judith Pond blue crab fisheries. When I researched old newspapers, they were on rolls of microfilm, (1980s) but today many back issue of newspapers are on the net. The dramatic reversal of fisheries here should be in old newspaper reports over time. A study of the blue crab fishery 1912 to 1938 in Pt. Judith Pond would be especially interesting. If anyone in Rhode Island is interested in this project drop me an email.

I respond to all emails at tim.visel@new-haven.k12.ct.us.

Dr. Field and the Marine Experiment Station at Point Judith Pond 1896-1900
And Rhode Island’s Blue Crab Question?

One of the accounts I use in describing the history of organic matter in warm water impacting fish and shellfish habitats comes from PT Judith Salt Pond (once known as Great Salt Pond) in Narragansett, Rhode Island. This very large salt pond located along the southern Rhode Island coast split between two communities of Narragansett and South Kingston was the site of the first marine laboratory built as part of a Land Grant university. It could be classified as the first Aquacultural Experiment Station in the United States. Created in 1896 after a summer (1895) immense fish and shellfish kill in PT Judith Salt Pond, the marine experiment station was a result of fisher concern and by 1898 already had a series of fact sheets/bulletins issued by Dr. G.W. Field. Unfortunately some email communications a few years back with the Rhode Island (University) Experiment Station indicate these early facts sheets may have been misplaced. It is unfortunate because fact sheet #7 (bulletin #50) was titled, “The Nitrogen Problem.” It would have been very interesting to read about the “nitrogen problem” that Dr. Field was studying in 1900.

Dr. Field’s marine experiment station, although in operation for only four years, conducted habitat studies at a very important period — those years in which cold water fisheries collapsed in New England (IMEP newsletter #55:The fall of New England Cold Water Fisheries October 2015, Blue Crab Forum, eeling/oystering/shellfishing thread). The die-offs of fish and shellfish in high heat meant great hardship for small boat fishers then (who were often very poor) who fished the shallows with meager equipment: a skiff oyster/clam rakes eel and flounder spears and pole (push pull) nets for scallops. They most likely looked to Dr. Field for both answers and help as he was an early supporter of aquaculture and who followed the policies of the first Agriculture Experiment Stations to provide direct, applied research benefits to farmers. Fishers in Rhode Island most likely looked at this Buttonwood Point marine station for much of the same help.

Dr. Field was quick to investigate the oyster fishery loss in Pt. Judith Pond and had come to the conclusion about the loss of the salt pond oysters were from organics being carried down the Saugatucket River (Narrow River), see CT Rivers Lead Sapropel Production 1850-1885 IMEP #26 Blue Crab forum, eeling oystering/shellfishing thread and he was very direct as to the cause. From the report of Dr. G.W. Field to the Annual Report of the Commissioners of Shellfishers made to the General Assembly, May Session, 1990 contains this section.

“STATEMENT OF DR. G. W. FIELD,
OF THE R.I. EXPERIMENT STATION, WHICH HE KINDLY FURNISHES THE COMMISSIONERS OF SHELL FISHERIES, AT THEIR REQUEST, FOR PUBLICATION”

“The biological department of the R.I. Agricultural Experiment Station, under the direction of Dr. G. W. Field, began in July 1896, the investigation of the cause of the decline of the oyster fisheries in Point Judith pond. Within the past twenty years, the supply of oysters, previously so bountiful, has rapidly diminished, and at present they have all but disappeared. The details of the investigation are published in the 9th Annual Report of the R.I. Agricultural Experiment Station, Kingston, R.I., 1986.

In brief, the cause of the decline was found to be the deposition of sediment upon the oyster beds; a condition brought about by the repeated closure of the breach, thus making the pond a settling basin for the silt brought down by the Saugatucket River. The silt and detritus, settling upon the oyster beds, kill the oysters by smothering. As a remedy for this a permanent breach was recommended.”

Dr. Field’s research targeted coastal energy; the opening of a breach inlet that had been closed (inlets during The Great Heat [1880-1920] tended to heal). Here is the first accounts of black water death as in high heat these areas succumbed to bacterial respiration as sulfides increased these fish kill events; residents on the Cape Cod and Islands have similar histories and would reopen such closed inlets immediately. He urged that a permanent breakaway be made which had closed up to allow minor tidal
exchanges to increase - no doubt that was a popular position of small boat fishers; those who would watch this “stagnation” occur. (IMEP #11 Historic Climate Impacts to Fisheries on the Blue Crab Forum eeling/oysters/shellfishing thread.

The heat during this period would cause habitat failures all along the New England coast. He was investigating changes in the plankton community in addition. As we know, from Brown harmful algal blooms (HABs) of more recent times, this would have happened as well in response to heat. To further the study of plankton, he commissioned a device termed, the planktonokit — a huge centrifuge that he was using in the study of Cyanaphceae, a type of blue green algae we know as cyanobacteria. This device (see Proximity to Sea Coast: G.W. Field and the Marine Laboratory at Point Judith Pond, Rhode Island, 1896-1900 by C. Leah Devlin, Ph.D and P.J. Capelotti, Ph.D. Journal of the History of Biology 29-251-265, 1996) could obtain speeds of 4,000 revolutions per minute enabling biologists to study “more successfully these lowly forms which lie close to the basis of life,” bacteria. Dr. Field (according to Devlin and Capelotti in their 1996 review of this lab, which is a great account of this effort), had come to review “coastal energy” long witnessed by coastal fishers. What could happen to small coves and ponds cut off from cleansing tides and cooler ocean water, which naturally held more oxygen? Fishers since the first early colonial records have reopened such inlets that have been closed by storms and moving sandbars. These barrier beach inlets and spits move and in times of heat (usually with lower coastal energy during the period from 1880-1920, especially 1890 to 1910) they tended to “heal” or close. Here are some of the first accounts of black water deaths as in high heat these shallow, hot habitats succumbed to bacterial respiration as sulfides increased to increase these fish kill events. Fishers have long known the dangers of sulfate organic reduction – releasing toxic sulfides – they smelled it {H.W. Harvey of the Marine Biological Station Plymouth, England was one the first researchers to make a direct organic matter – sulfide – sulfate reduction link. Writing in a January 1938 paper titled Biological Oceanography” and republished by the National Research Council, Washington, D.C.- US Geological Survey (Appendix #3). (Parker D. Trask editor in 1955 – Library of Congress catalog card number 67-26966 – Recent Marine Sediments)}. “One may assume that much of the soluble organic matter which dissolves into the water when plants and animals die or are killed is utilized and built up into the bodies of bacteria, and it follows that organic detristus consists, to some extent, of dead bacteria. Close to the bottom and in the surface layer of bottom deposits, bacteria are numerous. They bring out changes in the organic detritus, converting it to “marine humus,” which is in its nature similar to humus formed on land. With age, that is, with continued bacterial attack, this marine humus undergoes further change; the ratio of carbon to nitrogen, in the organic matter in muds tends to increase with increasing depth, that is, with increasing age, of the deposit. At a variable distance below the surface of marine deposits containing organic matter, conditions may become anaerobic and bacteria utilize sulphates as a source of oxygen, setting free hydrogen sulphide. The material becomes blackened with iron sulphide. A black layer is commonly found some inches below the surface of a sandy beach where this has occurred, and where subsequent oxidation of the iron sulphide sets free sulphur.”

As with the local fishers, no doubt Dr. Field soon urged that a permanent breachway be made into Point Judith pond and is quoted by Devlin and Capelloti (1996) as stating that the increased deposition of sediment from the Saugatucket River was “transforming the beautiful sheet of water [Point Judith Pond] to a miasmatic bog hold” certainly should have boosted his favor with local fishers during this period who sought a return of previous “cold water fisheries” (appendix 1) in now growing heat or hot “terms.” (For more complete review of the miasmatic/germ theory debate see Blue Crab forum™ Environment and Conservation thread report #6 Bacteria, Disease and Warm Water Concerns 7/23/15).

Unfortunately, the Great Heat and the collapse of inshore fisheries was to end both fisheries and sadly this first marine experiment station. Devlin and Capelotti (1996) detail the loss of fisher support; some who no doubt who looked to Dr. Field for direct answers (and prompt solutions perhaps) as to the decline of local fisheries. He was, as their livelihoods, both destined for failure from this very hot climate cycle. Very few researchers looked then at climate cycles for habitat failures as Europeans researchers also struggled with rivers full of organic matter which rotted in heat and gave rise to the Saprobien System a decade later. He was limited by what he could do and relied upon terrestrial techniques and reproductive capacity we know as spawner sanctuaries. Dr. Field repeatedly lost his desire to help fishers when 8 bushels of spawners (bay scallops) he procured were placed in Point Judith Pond were then harvested. He penned some negative criticisms of overfishing; alienating his contingency and the small boat fishers he needed for support. That was unfortunate but this continues today; a person that had so much assigned values and perceptions among those that had so little. To those fishers (and from accounts from other states) their livelihoods and ability to feed their families had gone; there was no spawner capacity when supper was just a few hours away. To those who did not face hunger or the motivation to help those that did, often did not share the same beliefs and values about the future. This reality would often drive a wedge between fishers and fishery managers as it quickly did apparently with Dr. Field. The immediate need of food does include values, beliefs and shared perspectives beyond those who perhaps never personally experienced this need.

Norman Borlaug, the “father” of the Green Revolution, responded to critics in a similar fashion, but instead of spawners, it was tractors and fertilizer as a Wikipedia account describes his rebuttal of critics for the use of fertilizer to produce food, commenting:

“Some of the environmental lobbyists of the Western nations are the salt of the earth, but many of them are elitists. They've never experienced the physical sensation of hunger. They do their lobbying from comfortable office suites in Washington or Brussels...If they lived just one month amid the misery of the developing world, as I have for fifty years, they'd be crying out for tractors and fertilizer and irrigation canals and be outraged that fashionable elitists back home were trying to deny them these things.”

The Importance of Fisheries History -

One of the advantages of environmental marine fishery history is to be able to go back and look at the fish catch reports, climate records and habitat conditions that fishers themselves witnessed. The accounts of Point Judith Pond is a classic and characteristic descriptions of high heat, low energy flushing conditions. By 1895, it was reported that ox teams could cross the breachway across the pond and lead to slow stagnation in heat. Opening it would alter the habitat succession cycle, but I suspect locked in the cores of organic deposits on the pond bottom would be a series of organic debris layers that formed Sapropel from sulfate-reducing bacteria — a source of ammonia and sulfides from previous habitat reversals long ago.

As for the marine laboratory, I suspect as fishers became more desperate or frustrated, they turned against Dr. Field; there was no quick fix or easy solution. The Great Heat would devastate New England cold water fisheries as it would these inshore fishers. A Narragansett Bay die off of lobsters had occurred in 1898. There was very little that anyone could do to prevent it. The local support of the lab dwindled as did perhaps the cold water fisheries and after being asked to teach a course at another marine laboratory in Woods Hole, Massachusetts, he never returned.

Six months after Dr. Field’s station was closed, residents of Narragansett asked for a permanent breachway into Point Judith Pond.

What happened later (always apart of my research), Charles Beebe of Beebe Marine in Madison, Connecticut where I worked during high school, purchased a small retirement home on the shores of Point Judith Pond. I would visit him while going to the University of Rhode Island (URI) Fishery School in the mid-1970s. One of the items we discussed, that according to him local residents once told of, was a huge blue crab fishery in Point Judith Pond around the turn of the century; he would welcome me to “Rhode Island’s Blue Crab Capital.” In the 1970s, I dismissed this statement as a humorous quote. It wasn’t; Point Judith Pond at one time was Rhode Island’s blue crab center. That blue crab fishery ended according to accounts from Mr. Beebe in the 1940s when Point Judith Pond now iced up when it got colder, (a growing negative NAO period) but at one time it was Rhode Island’s blue crab capital; what oral history continued for the area was in fact correct. When I bay scalloped on Point Judith Pond from 1978-1979, it had a bay scallop fishery but oysters were scarce. When our current warm spell accelerated, oyster sets became more frequent and intense, especially in the upper salt ponds now called Pettaquamscutt shores. Point Judith Salt Pond would be an interesting habitat history project, that was a multidisciplinary approach, combining core studies, climate reports, catch statistics, Rhode Island shellfish reports and Lobster Hatchery reports (Wickford Station) would provide the best results (my view).

Blue Crab Habitat History - Point Judith Pond

For the blue crab, the 1898 lobster die-off seemed insignificant like two ships passing at night; one was leaving port while another was just arriving. See IMEP #53, The Southern New England Lobster Fisheries Collapse of 1898-1905. Would Dr. Field have seen the blue crab ship arrive at Point Judith Pond? You bet he would have. By 1906, blue crabs had arrived in Narragansett Bay in great numbers. The reports of Rhode Island fisheries Inland fisheries reports mention it; terming it the “crab question.” By 1912, blue crabs were extremely prevalent in Rhode Island and Jefferies’ writing in 1966 still mentioned that blue crab abundance in his account in Chesapeake Science, Vol. 7 #3 on pages 164-170, in the fall of 1966:

Internal Condition of a Diminishing Blue Crab Population (Callinectes Sapidus) by H. Perry Jefferies, Graduate School of Oceanography, University of Rhode Island, Kingston, R.I. related the decline of Blue Crabs in Rhode Island waters “Abundance of the Blue Crab (Callinectes Sapidus) Rhode Island estuaries has decreased during the last 30 years. A commercial fishery once existed in areas where the blue crab is no longer found. Composition of the plasma and muscle was studied to see if abnormalities could be recognized.”

and further;

“Early reports of Rhode Island Commissioners of Inland Fishers 1900-1914 [during the warmest period - T. Visel] indicate the blue crab once occurred in sufficient abundance to support a small industry. Several bushels could be caught in a single morning with a baited line and dip net. In recent years, the blue crab has become scarce in the estuaries of southern New England fishery statistics do not accurately reveal this decline because most of the commercial catch was sold directly by individual fishermen and never passed through warehouses.”

“In the mid-1930s the decline began. By 1938, the blue crab was so scarce that commercial fishing was no longer profitable. Fishermen say the last significant run of crabs into Point Judith Pond, Rhode Island occurred in 1947. No blue crabs have been seen here by the author over the past seven summers (1959-1966 was some of the strongest negative NAO periods - T. Visel) and shell fishermen say they are rare indeed; only one crab was caught during an intensive 2 year trapping program for lobsters near the mouth of the Bay” [Narragansett].

Although accurate about the history of abundance, Jefferies looked to biological factors, not environmental conditions for the blue crab decline. He looked at plasma (biological) for a plausible reason for the decline — as what often happens not environmental habitat quality from climate cycles. The concept of climate cycles was still in its infancy; the midwestern farmers were to learn this habitat history lesson of reduced rain and tilling dry soils called dry farming a century ago; it was a painful, hurtful lesson. But dry farming held a precarious grip on the midwestern heartland; a small change in rainfall overtime could have tremendous habitat consequences. The same occurs in the marine environment and most notably in shallow areas closest to land. The study of marine habitat succession has a direct climate cycle link if there was no climate cycle, there would be no long term marine habitat succession. Habitats that are unstable generally prevent succession in these coves and salt pond they lasted decades. Those cycles can be found today in deep slices of the coves of salt pond bottoms profiles called cores.

In the absence of fisher observed cycles, rises and falls in seafood abundance is often attributed to our actions — the usual issues: pollution, coastal development and overfishing and often (nearly always) it is none of these, but a dramatic increase or decrease in habitat quality – first reported by those whose livelihood depended upon those habitats – fishers.

We would have many habitat quality questions answered about blue crabs and perhaps many other species, if this marine laboratory had remained open and fisher support continued. I contend yes. Dr. Field was already looking at marine soils and bacteria; he would have studied the increase of blue crabs reported by fishers and looking at the number of bulletins he had already issued (see appendix) in four years, I am certain many of them would have mentioned blue crabs. The last waves of blue crabs appeared in Point Judith Pond according to Jefferies in 1947 as the negative NAO stated to take hold in New England; it was for a time getting colder. He would have logged entries as to the arrival of the blue crab in Point Judith Salt Pond. When the blue crabs did arrive, Dr. Field was working at Woods Hole, Massachusetts.

Appendix #1
The Fisheries of Point Judith Pond - 1887
United States Commissioner of Fish and Fisheries
The Fishing and Fishery Industries of the United States Geographical Review of the Fisheries,
pg. 308
Rhode Island - Washington County, Rhode Island
Section II 1887 Washington APO
Section 102 Point Judith to Pawcatuck
By A. Howard Clark Part IV

“Point Judith - In the rear of this promontory lies Judith Pond, 6 miles long and 1 mile wide; the water is blackish and is from 8 to 12 feet deep. Formerly oysters were very plentiful, 10,000 bushels having been taken out in 1870. The mouth of the pond has become so filled up that now no oysters are to be found. The water having stagnated for want of free circulation. The bass fishery has on that account also failed. Ten thousand dollars has been realized by one owner on the capture of bass. Now that business is entirely at an end, a small outlet still permits the entrance of alewives. The fishery is carried on from December to June by farmers, mechanics and fishermen. Last spring (1880) smelts were a little more abundant. Perch are still taken in large quantities. Most of the fishing operations are conducted by the use of fifteen seines, traps being out of the question where the fish average is so small. The average length is 100 fathoms, depth 18 feet and mesh from 1.5 to 2 inches.

In winter, heavier seines are used requiring six men to haul. Perch and some bass are then taken. Twelve years ago (1875), 198 barrels of bass were taken at one haul. In spring, the catch is confined to alewives of which 2,000 barrels were taken in 1880. The alewife seine has a light thread and is handled by three men. Smelts are taken from February until the end of March. One hundred and fifty eel pots like small fyke nets (eel fakes) are set in spring and fall, being baited with crabs (presumed to be Horseshoe crabs – T. Visel).

The investment here in seines, eel traps, boats and fixtures is 3, 375, the value of the product, which consists of 500 bushels of clams, 2,000 barrels of alewives, 60,000 pounds of smelts, 60,000 pounds of perch and flat fish and 4,000 pounds of bass, is 10, 800. The number of persons engaged is 60.”

Appendix 2

State of Rhode Island and Providence Plantations
ANNUAL REPORT
of The
Commissioners of Shell Fisheries,
MADE TO THE
GENERAL ASSEMBLY
AT ITS
MAY SESSION, 1900.
___________
PROVIDENCE:
E.L. FREEMAN & SONS, PRINTERS TO THE STATE. 1900.
25

STATEMENT OF DR. G. W. FIELD,
OF THE R.I. EXPERIMENT STATION, WHICH HE KINDLY FURNISHES THE COMMISSIONERS OF SHELL FISHERIES, AT THEIR REQUEST, FOR PUBLICATION

The biological department of the R.I. Agricultural Experiment Station, under the direction of Dr. G. W. Field, began in July, 1896, the investigation of the cause of the decline of the oyster fisheries in Point Judith pond. Within the past twenty years, the supply of oysters, previously so bountiful, has rapidly diminished, and at present they have all but disappeared. The details of the investigation are published in the 9th Annual Report of the R.I. Agricultural Experiment Station, Kingston, R.I., 1896.
In brief, the cause of the decline was found to be the deposition of sediment upon the oyster beds; a condition brought about by the repeated closure of the breach, thus making the pond a settling basin for the silt brought down by the Saugatucket River. The silt and detritus, settling upon the oyster beds, kill the oysters by smothering. As a remedy for this a permanent breach was recommended.

The later work upon the conditions in Point Judith pond upon the general economic value of the pond as a source of food supply. Experiments were carried on for determining the amount of food in the water available for shell-fish and for economic food-fishes, for the purpose of ascertaining the quantity of fish and shell-fish which could live there. The comparisons by chemical and planktological methods showed that the food conditions in the pond compare favorably with those in Great South bay, Long Island, N.Y. (the native home of the Blue Point oysters.)

Experiments upon artificial fertilization of the water, analogous to the method of chemically fertilizing the land for crops, demonstrated that it was feasible to increase the growth of plants in the water through the addition of chemical plant-foods, and thus render the water capable of supporting a greater quantity of animal life. These experiments were subsequently suspended, and have not been carried to the conclusion of demonstrating the feasibility from an economic point.

In addition to the above, considerable work has been done on the economic fauna and flora of the pond, and upon the physical conditions governing marine life in the pond. An accurate survey of the bottom has been made, giving depths of water and of mud, among other details of currents, temperatures, specific gravity, tidal influences, etc.

The biological department has published and will send to any resident upon application, the following, bearing directly upon questions connected with the shellfisheries of the State:

1. Oysters in Point Judith Pond, 9th Annual Report of R.I. Agricultural Experiment Station, 1896, pp.173-186. 26
2. Point Judith Pond, 10th Annual Report, 1897, pp. 117-165.

3. Methods in Planktology, 10thAnnual Report, 1897, pp. 117-165.

4. The Star-fish in Narragansett Bay, 10thAnnual Report, 1897, pp. 117-165.

5. Report of Biological Division, 11thAnnual Report, 1898, pp.94-96.

6. Report of Biological Division, 12thAnnual Report, 1899, pp.123-124.

7. The Nitrogen Problem. Bulletin No. 50.

8. The clam. The Cultivation of Tidal Mud Flats. Bulletin No. 51.

Appendix # 3

Biological Oceanography – Manuscript received January 15, 1938
H. W. Harvey – The Marine Biological Station Plymouth England
Reprinted in 1955 by the subcommittee of the committee on Sedimentation of the Division of Geology and Geography of the National Research Council, Washington DC. Original Copyright 1939 – London, Thomas Marby and Company 1 Fleet Lane, E.C. #4

Several observers have found that sea water contains only a few bacteria per cubic centimeter, which will grow on nutrient media, provided the water is collected well away from land and does not contain planktonic plants or animals, with which bacteria are usually associated (26). The ratio of total bacteria to those which will grow on nutrient media has also been investigated (1 Cool

. This bacteria flora in the water of the oceans, although sparse, except in the vicinity of land, can and does, bring about notable changes – particularly the cycle which results in the breakdown of proteins, with the final production of nitrate.