The Search for Megalops
“You Don’t Need to be a Scientist to Report”
Megalops #1 March 1, 2019
In the Great Heat 1880 to 1920 Blue Crabs Dominated Shore Catches
Blue Crab Populations “Retreat” In Colder Periods
What will next year bring?
Thoughts on the Next Season – The Blue Crab Season of 2019
• The Lobster Problem – The Blue Crab Cycle of 1898 - 1998
• Climate Indicator Species for New England Lobsters and Blue Crabs
• Large Crabs dominate New England catches the 2018 Blue Crab Season
• Long Term Observations are important – Jeffries, University of Rhode Island 1966 study
• Shallow Water Habitat Reports are few from the last century
• Sapropel and the Blue Crab A Note From Tim Visel
The NAO cycle of heat and drought is now being examined for patterns of seafood. The shell middens left by New England’s first inhabitants are providing clues to the heat/dry periods and those that are more wet and colder. It was the dry periods that brought devastating forest fires, and the wet (and this includes tropical moisture) the floods. It seems that New England Native Americans knew this from the cycles of bluefish, which are abundant in hot periods. These dry periods are also known to be associated with an increase of forest fires (an early great concern to early CT settlers). According to Elizabeth A. Little, Bulletin of the Massachusetts Archeological Society, Vol. 47, No. 2, October 1986, it seems that Native Americans knew this about bluefish and fire relationship as well:
“Bluefish have disappeared from Nantucket waters for varying periods of time according to legends and records. The Indian legend says that in prehistoric times they disappeared and an old chief prophesized that when Nantucket suffered a disastrous fire, the blue fish would return. The legend is still remembered, and at times events have convinced some people that it is true.”
In our past, hot dry cycles were times of greatest forest fire danger.
One of the experiences this past season was if you found the crabs they were very hard shelled and packed with meat. That was one of the positive comments this past year – “The crabs I caught were packed with meat” and they were. However, very hard shells are also a sign that crabs have stopped shedding and that the reproductive season is both shifting and getting shorter. I was predicting another “split winter” similar to that of 1957-58 winter, which started very mild then ended very cool. That has been the pattern of the past three winters, a warm fall but very cool spring. From observations of megalops sets in just 8 years (2010), the small blue crabs are showing in October to November instead of in May to June, a 90 day or more difference – a huge change! Last spring was very cold and snow lingered into just before the official CT Blue Crab Season opened. It snowed just two weeks before our season opened May 1st, and winterkills were reported along the eastern seaboard. Chesapeake Bay was especially hard hit, and if you ever hit ankle freeze or ankle ice on muddy bottoms, it is an uncomfortable sensation. The bottom few inches remain soft but super chilled seawater; it is frozen much like a grass tundra, soft on the surface yet frozen below. This occurs in shallow waters that, at low tide, have groundwater seeping upward – at low tide allows nearby groundwater to move up and freeze below super cooled seawater at 28oF or 29oF. From the surface, it looks normal but below, it is frozen. One of the few times I observed this was on Cape Cod. The bottom ice had frozen around soft shell clams and had, in some areas, lifted off the bottom (this is usually black ice). This can be a winterkill by cold. However, we also have a sulfide winter kill when ice or snow cuts off the oxygen below, the soil becomes oxygen poor and purges toxic sulfide, the sulfur deadline or sulfur “stinks.” Most estuarine organisms can take a mild ankle frost, soft shells, oysters and even winter flounder have a type of antifreeze that if not moved can survive some freezing but not the blue crab. Here starvation can occur as well.
Reports from Chesapeake Bay last year mentioned a winterkill, but which one or all three? Is the presence of large adult blue crabs a sign that some of the overwintering habitat has changed for certain ages or sizes? The timing of appearance of small crabs in late fall means perhaps they do not have time to store food for the long winter ahead. These conditions relate to the NAO, a climate cycle just now being discussed, but described by fishers as “cycles.”
Hoping all blue crabbers have a great 2019 Blue Crab Season. I want to thank all the blue crabbers who e-mailed me reports or who asked questions. I appreciate the interest and support. I respond to all e-mails at
[email protected].
The Lobster Problem - The Blue Crab Cycle – 1898-1998
Students interested in the 1998-2005 lobster die off should read the J. W. Collins 1904 report of the Boston Massachusetts 1903 lobster Convention. With the dieoff of 1898, fishers saw decreasing lobster catches with increased gear/effort the catches in southern New England were dropping except for Maine. With winters relatively mild a winter lobster fishery had opened in Maine and landings continued far beyond the “summer trade” now into the winter months as well. Within a year Tarpon would be caught in Narragansett Bay – oysters were setting in areas long absent of natural sets. The bay scallop fishery and southern lobster trade were in “ruins” a term used to signify a dramatic decline in landings. At the turn of the century the climate had turned against lobsters and the bay scallop. The lobster fishery being more important obtained nearly all of the public policy attention, yet the increase of the blue crab just a mention or “question.”
The 1903 lobster convention was convened as lobster landings dropped in shallow waters in Southern New England and resulted in more uniform size laws, protection of egg bearing females and the continued construction of lobster hatcheries. The Boothbay Maine Lobster Hatchery was under construction in 1903 and soon would become the nation’s largest releasing hundreds of millions of stage 4 lobsters along Maine’s coast.
And climate change – it barely got a mention at the 1903 Lobster Convention although some speakers mentioned it briefly. The Blue Crab however was flexing its habitat muscle and as evidenced by a growing commercial blue crab fishery in Narragansett Bay (See H.P. Jeffries, University of Rhode Island, 1966 observation).
By 1906 the full extent of the great heat 1880-1920 climate periods would begin to cause great concern as lobster landings continued to plummet. In six years Blue Crabs in Narragansett Bay would peak in 1912 as Black Sea bass filled the Rhode Island trap nets.
Although tens of thousands of city residents rushed to shore (resulting in a booming summer trade along the coast) to escape the heat waves that killed those unable to keep cool and hydrated the concept of heat impacting coastal fisheries was largely ignored. Some mentioned temperature as Spencer Baird, Director of the U.S. Fish Commission, did but comments at the time included that nature had its own agenda.
As more information comes forward (much thanks to the Atlantic States Marine Fisheries Commission for reprinting in its entire form IMEP #53 and on April 6, 2017, IMEP #62, February 2, 2016) southern New England lobster fishers now know that this has happened before.
Climate Indicator Species for New England, Lobsters and Blue Crabs
Thanks to the Atlantic States Marine Fisheries Commission Lobster fishers can read a small part about the 1898 – 1905 lobster die off (February 22, 2016) in southern New England. Although individual states have century old lobster hatchery reports these are being put on line by Hathi Trust and the University of California at Berkely. Each report contains important lobster habitat observations from over a century ago. A few years ago, I was able to attend the Maine Fishermen’s forum held at the Samonet Resort in Rockland, Maine 2016. It was an excellent meeting with many thought provoking conversations about lobster megalops survival (which has been in decline suggested by changing wind patterns) lobster habitat carrying capacity, reproductive capacity and predation, especially the decline in cod, a predator of so many small lobsters. In the background of most of these conversations were climate change and impacts to the New England lobster fishery. But New England’s Blue Crabbers have no similar industry representation. From the historical reports in Rhode Island, Massachusetts, and New York commercial blue crab fisheries soared when lobsters were in decline. We also have the 1950’s and 1960’s reports of the decline in blue crabs and Massachusetts commercial landings ended around 1935, Rhode Island in 1945 and New York around 1961. Connecticut’s ended in the late 1960s. It is interesting to note that commercial landings ended in the north first, and in the 2000s, blue crab surged in the opposite pattern – southern areas first, then spreading north.
Cooler waters meant in time more lobsters in southern range and less blue crabs and this shift responds to long-term climate shifts, the North Atlantic Oscillation or NAO (See the October report (2018) titled “Large Shifts In Commercial Landings of Estuarine and Bay Bivalve Mollusks In Northeastern United States after 1980 with Assessment of the Causes,” Mackenzie Tarnowski, Marine Fisheries Review, 80 (1)).
The relationship between lobsters and blue crabs is now very strong and with cooler winters (colder winters) since 2011 – blue crab habitat expansion has stopped and is in decline. Greater numbers of New England’s blue crabs are under “habitat compression” greater numbers of adult blue crabs are being compressed in smaller suitable habitat areas like salt ponds (termed habitat refugia). If you crabbed in these refuge areas (deep holes with sapropel – 1 and had good access to sea water, your catches went up. If you fished in areas at the height of habitat expansion in 2008-2010 or the open shore, chances are your catches were lower. In fact the “waves” of crabs moving at night appears to have also stopped. These waves are now thought to originate from tidal rivers that have bivalve shelly bottoms. The “river” crabbers have done much better than those who fished near the shore (observations and reports) and by late August in the difference in catch rates apparent – shore 0-2 crabs per hour, rivers 8 to 10 crabs per hour. Some great catches using shallow trot lines were made in lower CT River (See Megalops report posted December 3, 2018, Northeast Crabbing Resources Thread, The Blue Crab ForumTM).
I visited the mouth of Clinton Harbor (Hammonasset River) about a dozen times between June and the end of September and no crabbers. So in one of my last trips, I asked some fluke fishers at the mouth of the Hammonasset River about blue crabs and the response was “They never arrived.” However the blue crabs were way up river sometimes above the Route 1 Bridge, perhaps they overwintered there.
At the same time, reports came in regarding dense concentrations of blue crabs above the Route I bridge of the same river (in deep holes at bends); nothing was at the mouth. The crabs, it seems because of the drought, never left the upper rivers, leaving one option, that heavy rains from time to time could move them out into the saline waters below. The heavy rains/floods never arrived (dry conditions) early this summer so the crabs stayed in the upper rivers all summer? The Mystic River this summer was very good for crabs above the Seaport and the site of a long-term blue crab tagging project. When this blue crab tagging project is completed, we will know much more about blue crab movements and populations in eastern Connecticut.
In July and August came some reports from marina and pole crabbers and those crabbers at night that beam light on the docks and poles. At night on very hot days, the oxygen tension is low between 1:00 a.m. and 4:00 a.m. in the morning as sulfides seep from Sapropel – 1 in dredged areas and crabs now move toward the surface. Poles and dock floats are perfect places to wait out this low oxygen /sulfide event. As the first light of dawn appears, plankton now begins to generate oxygen and offset bacterial sulfide reduction of bottom sulfides and crabs leave these nighttime “perches” for the bottom again. By 7:00 am the sulfides are dissipating and crabs return to the bottom and search for food. Plankton now adds to the oxygen supply and sulfide “smells” in the water of early mornings subside. This occurs in the heat of the summer and many coastal residents notice that on calm hot nights the salt marshes smell like sulfur late at night but as the south westerly breeze develops (often at sunrise) it is gone. It is that 1:00 am to 4:00 am time when sapropel purges sulfides – “the rotten egg smell.” If these events are long enough sapropel (1) with oxygen turns sapropel (2) without it and the rise of sulfides. If the heat continues sapropel (3) may bleed into sapropel (2) and here the pungent earth or compost smells of ammonia sulfide mixed with methane gas. Bacteria in sapropel (3) often called “the methanogens” do not need oxygen at all; they can strip and derive energy from the carbon chains themselves breaking them into single carbon atoms surrounded by four hydrogen (CH4 – methane gas or natural gas). It is in these organic deposits that ammonium surges the nutrient supply for macroalgae, such as sea lettuce.
That is why so many landfills today have gas taps draining off (or sometimes harvesting) this methane natural gas – we have created sapropelic conditions by burying organic matter (food, garbage, leaves, etc) and sealing in off from oxygen bacteria giving those who can break certain carbon chains without oxygen and emit much smaller molecules – methane a place to grow. (In the agriculture community, eliminating oxygen in manure has much the same impact, but instead of sapropel it is termed digestate).
We have created the ideal habitats for these bacteria – in the “landfills” of garbage and organic debris and if we were able to examine the processes we would see the formation of sapropel type 3 – a black viscous liquid that is the foundation of what we call oil from decades of bacterial “meals.” It is this fluid that can nourish terrestrial crops as understood by early Connecticut farmers (See IMEP # 26 posted on September 29, 2014, Connecticut Rivers Lead Sapropel Production 1850 to 1885).
The habitat quality for blue crabs is dependent upon organic matter, energy salinity, temperature, oxygen and bacteria. In smaller bodies of water such as salt ponds and rivers these factors are greatly magnified especially when they become isolated from the sea. They heat and cool faster. Lobsters do better in cold and high oxygen environments perhaps lobsters and blue crabs could become key indicator species for climate impacts recorded by catches. In the Long Island Sound the shallows are key to understanding this reverse of species with at times could be measured in centuries. The source of this habitat information is dependent upon its fishers – my view, T. Visel.
Large Crabs Dominate New England Catches
One of the features of this blue crab season to date (2018) has been the dominance of large “rusty” crabs this season, the second has been the warm water cut off from the shore as a slight change in wind direction (This shift in wind tends to move coastal water from the shore, allowing subsurface waters to upwell). This second feature has happened before to shore (shallow water) crabbers, as the waters warmed blue crabs came into the shallows here within reach of the hand liners. It is during the peak “heating” that blue crabs move to deeper cooler waters. Kayaks and small boats enable crabbers to reach these cooler deep holes or deeper river bends. This is also a clue to the “dropoffs” - I have seen what happens when the incoming tideline hits low tide resting crabs, they immediately sense the “new” oxygen (and perhaps the increase in salinity) and begin to move. The opposite may happen when they leave the bottom sensing lower oxygen. When I crabbed in Tom’s Creek in the 1960s I was exposed to a Yale University study which looked at the tidal oxygen exchange in the creek; as the tide ebbed life (motion) came to a standstill, blue crabs then buried themselves; they would when challenged raised their claws but did not leave the bottom. This abruptly changed when the incoming tide line (water change) hit them within - suddenly it seemed everything was swimming and moving again. It was very hot during this August study so the creek ebb flow was very warm and was then oxygen “poor”. The change of tide was like a huge wake up call for sea life on the bottom of Tom’s Creek.
From many shore crabbers conservations this summer the incoming tides brought the same active hungry crabs, at slack high crabbing paused followed by ebb time complaints about increased drop offs – I think this might be related to the Tom’s Creek oxygen study in the 1960’s? Crabs in deeper holes may not be this impacted as “boat” trap crabbing has consistently delivered higher catches (Megalops #8, August 23, 2013) and (Megalops #8, August 16, 2012) and might have higher oxygen levels if slightly cooler.
The second feature has been the occurrence of rusty or yellow face crabs this season. We did have reports of smaller crabs at the mouth of estuarine area of Clinton Harbor in July but a late August visit to Clinton Harbor – wonderful high tide a small breeze but no crabbers when I asked two snapper blue fishers they responded the crabbing was very poor. It has been upriver away from the saline waters that have produced the best catches. But what crabbers reported is very similar to what Jeffries 1966 reported in Rhode Island a “habitat compression” that crabs had populated what sufficient habitats were left in coastal salt ponds, deep holes and river bends that has been the most consistent crabbing places this summer. Some rivers are warmer because they obtain warm street water and saline waters collect near the bottom. Thermal “pollution” has been a concern for decades, but in this case, perhaps helping the blue crabs “hang on” here; we help raise temperature with lakes and ponds (Hammonasset River, Appendix # 1).
The rusty and yellow face crabs have extremely hard shells, and like hard shell lobsters contain much more meat and now dominate populations in much of our area, the prediction is for another split winter – a warm fall and a very cool/cold spring. Time will tell.
Long Term Observations are Important
Will blue crabbing improve or decline? Why do we have crabs this year and the following year very few? These are the same two questions that get asked by blue crabbers in every week. Most of the blue crabbers I have met this year all mentioned how poor (generally) the crabbing was last year asking why? I respond that it is unclear – we really don’t know and I believe in our area it is linked to temperature and storms. But habitat memory can be very “short” most crabbers do recall the great 2008 to 2011 seasons but the storms and cold that followed have faded into this past summer’s heat. We really do not have a good habitat knowledge base (other than observations) that has a climate footing. It may seem ironic to see that in print with all of today’s climate change discussions but it is true nonetheless. Last spring, the Connecticut River developed an ice jam. Icebreakers were summoned from Maine. This summer was then very hot.
In geologic time, five years is just but a second but we do have observations from the 1800’s. After the warmer 1850s and 1860s it was brutally cold in the 1870s, cattle froze to death outside of barns in Connecticut and temperature 30oF below zero, entire apple orchards were destroyed (See Special Program Report #3, The 2013 Blue Crab Year, posted on May 30, 2013, The Blue Crab Forum™. Ice was so thick in Long Island Sound it removed entire wharfs and pilings, and damaged previously built breakwaters. In this cold lobsters were on the beaches close to shore, bay scallops flourished in Long Island Sound – Connecticut and New York fishing fleets landed codfish. Lobsters at times even extended in New Jersey waters. However after the 1870s as waters gradually warmed into the 1880s menhaden fisheries exploded. This change of temperature is modified by water, so it contains a habitat delay. While it started to warm in 1882 the great oyster sets of the 1890s came a decade later.
Oyster sets now occurred off Norwalk and New Haven harbors as blue crabs started to increase. By 1887, U.S. Fish Commission reports listed New Bedford to Wareham Massachusetts as supporting commercial blue crabbing, which would later peak in 1912. The blue crab low point from records I have been able to find the low point was around 1962-1965. Climate wise, its 50 year trends, with produced peaks here in New England the last two centuries in 1912 and 2010. After the 1912 peak blue crabs generally declined for the next 50 years, it was a negative NAO phase and more researchers are now recognizing the impact of the cooler 1950-1965 temperatures and increase in storms (energy) upon coastal seafood habitats. (See NOAA Report just released this October, 2018 titled “Large Shifts in Commercial Landings of Estuarine and Bay Bivalve Mollusks in Northeastern United States After 1980 With Assessment of the Causes”).
Other researchers have looked to other climate indicators, the spacing of tree growth rings, shell “rings” of bivalves, cycles of mosquito disease (always more intense in high heat) or food spoilage, especially bacterial illness. These factors can change quickly, but ocean waters take time to “heat up” and longer to “cool off”. That makes following trends in fisheries even more complex, this buffering ability of seawater makes abrupt changes in seawater rare except in the shallows where blue crabs live. That is often called winterkill, although without knowledge of the pH of sapropel the “winterkill” can be from several factors. That may help explain how quick blue crabs populations can change; they live in the shallows depend upon habitats most susceptible to both heat and cold, and more likely to show great changes in catches from year to year. It might take time but between 1898 and 1998 the cycle is quite clear. Unfortunately the decline in blue crabs here has been sudden and severe. In fact, media reports continue to mention high blue crab populations when in fact that is not correct. This points to a huge problem – the delay in real time data acquisition. The blue crab population in 2018 was just a fraction in CT as it once was in 2010.
Shallow Water Habitat Reports Are Few from The Last Century
When you examine landing and catch reports for blue crabs and lobsters, over time you can see this climate impact. But again it is 50-year to 100-year patterns. We really don’t have that much observation about historical bottom habitat conditions (except perhaps the oyster industry) because most of the research effort then was directed at our impacts by harvesting the seafood itself or the negative impacts of water pollution, or corrections to fishery management/conservation policies.
On land, perhaps the best habitat example is our brook trout, when, during the period of 1880 to 1920 the shallow cool streams these trout depended upon became very hot. Connecticut officials surmised that the native brook trout was nearly extinct and acknowledged this climate pattern in 1901. In response, State officials (Connecticut) started to introduce the more heat tolerant trout, brown and rainbow trout, while simultaneously supporting new facilities to replenish trout populations “the trout hatcheries”.
This also happened with the 1898 lobster die off, as New England states then built lobster hatcheries in response to the “lobster problem.” The surprise rise in blue crabs, however, was only then a “question.” Increased habitat quality typically comes as a surprise, whereas a decline is followed by increased blame – usually aimed toward the fisheries (catches). Most of the response around the lobster collapse a century ago was regulatory, with a close examination of our role (over fishing) while admitting in time a near absence of any post megalops lobsters in shallow waters, the construction of stage 4 lobster hatcheries soon followed. It was believed to be an absence of egg production was fishery related largely owing to over fishing (although natural conditions are mentioned at times), however, a near shore “high heat” habitat failure was more likely to blame. Tagged lobsters in 1904 (Wickford, RI) for example showed that nearly all the tagged lobsters headed out to sea (and cooler waters) from Narragansett Bay to the dismay of fishery managers. In 1914 as the Great Heat period (1880-1920) reached maximum heating, Connecticut fishery managers debated releasing trout (hatchery raised rainbow and brown trout) in New England streams at all. I think that ponds and lakes with cool groundwater springs provided the best chances for survival. It was at this time, 1912-1914, that Narragansett blue crab levels peaked.
The Blue Crab Cycle
Chesapeake Science Vol. 7, No. 3, pp. 164-170 Fall, 1996
Internal Condition of a Diminishing Blue Crab Population (Callinectes sapidus)
H. Perry Jeffries
Graduate School of Oceanography
University of Rhode Island, Kingston, RI
“Early reports of Rhode Island Commissioners of Inland Fisheries (1900-1914) 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.”
“Fishermen say that the last significant run of crabs into Pt. Judith Pond, RI occurred in 1947. No blue crabs have been seen here by the author over the past seven summers, and shellfishermen say they are rare indeed. Catches in Narragansett Bay are significant; only one crab was caught during an intensive 2-year trapping program for lobsters near the mouth of the Bay.”
It was the 1962-63 Rhode Island studies conducted by H.R Jeffries (1966) he did by observation and records of what are called “rusty” and “white belly” crabs that is of interest today. Jeffries conducted his study at the low point of the blue crab cycle in southern Rhode Island. For lobsters, it was the 1911 special report to the legislature of Massachusetts from the Commission of Fish and Game. This study was conducted during the low point of lobsters in Southern New England dating from the 1898 die off similar to the 1998 lobster Long Island Sound die off a century later.
The special report delivered to the Massachusetts House of Representatives in June 1911 by George W. Field, a decade after leaving his Rhode Island, Maine laboratory on Pt. Judith Pond, was titled “The Lobster Fishery: A Special Report Including Suggestions For Uniform Laws.”
It clearly sets the stage for a regulatory solution when in fact it was the result of climate conditions. (With southern New England experiencing another lobster dieoff from 1998 to 2005, which was exactly in the same geographic region 100 years prior, there were indications that another may have occurred from 1790 to 1815 (reports of cheap prison food running out to English POW’s Cape Cod Scarcity and CT vessels buying lobsters elsewhere). We need to look at the NAO – the cycles of hot and cold for perhaps several cycles, not just one or two – my view, T. Visel.
One can only guess what Dr. Field would say today, a century later with warmer waters, and after a second lobster dieoff, which would happen again in the same states he once worked. What is ahead for blue crabs I feel much can be learned from what has happened before - a shift to cooler climate will reduce them to the last warm pockets – the salt ponds, exactly what Rhode Island researcher Jeffries noted before in 1966.
The last large New England lobster hatchery in Boothbay, Maine would close in the 1950’s, as the cost of heating the seawater made costs rise to such a point that it was thought it was just too expensive to operate. When the Boothbay lobster hatchery was built in 1903, the waters were warm enough to sustain culture operations with little modification or pre treatment; by the 1940’s, cooler waters had returned necessitating boiler systems to pre heat this now chilly seawater before entering the hatchery. (Lost in the discussion 50 years later was the need to heat the seawater at all? T. Visel.) That is the problem with short-term views, forgotten is when the Boothbay lobster hatchery was built, incoming hatchery water was warm enough for culture (hatchery) operations. In a half century, the brutally hot 1890’s were just a distant memory; it had turned colder under the negative NAO (See Harry Van Loon interview arranged by Hans V. Storch for a discussion of the early research of the NAO, Defant, 1924). (See Defant’s work on North Atlantic Climate Variability, revisited S. Bronnimann, 2008).
That brings up the bias of “science” without a long-term view. John Hammond introduced meto this concept in 1981 and later Mervin Roberts reinforced it in his 1985 book titled “The Tide Marsh Guide to Fishes.” It was Mervin Roberts that urged that policy not be based upon such short term observations; in fact, this short passage delivers the message in a stern caution about the use of such surveys in public policy formation --- a bias, often repeated on Cape Cod a few years before (See Megalops #6, August, 2016) for a full discussion.
From The Tide Marsh Guide To Fishes (1985)
By Mervin F. Roberts
“Biological surveys and censuses are difficult to design and sometimes impossible to carry out so as to be free of bias. They are often hard to compare since very few are conducted under identical circumstances; but then even the accuracy of our national census of people is frequently challenged…
Now please come back to that word which appeared several paragraphs previous: bias. If you are a political or social activist you may have pounced on “bias” and wondered how scientists apply it. As a matter of fact, scientists used it long before it became a catchword. Examples of bias in science are sometimes found in collections of living organisms whose population is in motion. To be without bias, such a collection would have to be made over an extended period with no regard to inclement weather, ice, time of day or holidays.”
The climate period directly effects what seafood is more abundant relative to others. This rise and fall of seafood in the shallows is more responsive than that of offshore species because shallow areas are more “responsive” to rains, energy and solar heat. They indicate trends quicker and therefore fill in the missing blanks to fishery outcomes, especially when forage species change inshore over time.
During the decline of the lobster industry, in the early 1900’s for example, fishery managers relied upon JW Collins, a former researcher and writer for the US Fish Commission at the time. He lobstered off Nova Scotia as a boy in shallow waters. This is the statement of JW Collins during the 1903 lobster convention held at Boston Massachusetts. (This lobster convention would influence our response to the lobster collapse of southern New England, one towards greater regulation and the other accelerated the construction of lobster hatcheries for the next century).
“I can scarcely claim to be an expert regarding lobster, for I have been familiar with it and have had it under observation for more than it has been my privilege to make careful inquiries concerning it throughout its range of distribution in America from the Delaware Capes to the strait of Belle Isle, and also in northern Europe, where the lobster is a different species from ours’, but differs chiefly in size. As a child with bare feet and legs, I often waded into the sea on the coast of Maine to a depth of a foot or so, and pulled big lobsters from beneath seaweed covered boulders where they generally were found at low tide. When only ten to fifteen years of age I caught lobsters in the waters of Nova Scotia, Prince Edward Island, the Magdalen Islands and lower Canada. Later, I was a lobster fisherman on the coast of Maine, in 1879 and 1880 I collected information regarding the lobster and the lobster industry from Eastport, Maine to Delaware.”
When Captain Collins made this speech in 1903 at the Boston Lobster Convention, Maine’s lobster catch that year was thirteen million pounds in a century plus later 2013—127 million pounds.
The increases in the Maine lobster fishery with warming seawater creates a need to now take a step back from a pre-regulation approach and also include climate and habitat factors influencing catches (See Megalops Special Report #1 posted June 20, 2018, The Blue Crab ForumTM, Northeast Crabbing Resouces thread for Rachel Carson’s description of the arrival of codfish in Greenland, 1912). If J. W. Collins was here with us today, the increase in the maritime lobster catch would be perplexing. The regulatory approach did not help the southern New England lobster fishery, at the same time fishing to the north increased? The Lobster Convention of 1903 was to bring elected officials, industry, fishery, managers and lobster fishers together and discuss options that may alleviate “the lobster question.” During the meeting climate was barely mentioned a winter fishery, which was growing (and only four years after the 1899 Southern New England had an “ice famine”) and the State of Maine produced catch statistics that lobster catches there were actually increasing.
There is no regulatory approach to these climate patterns—by 1915 the weather pattern started to change and by the early 1920’s brutal winters returned--according to Jeffries, (1966)—blue crabs had also declined since the turn of the century in Rhode Island. The cold winters, although helping improve the bay scallop habitats in Narragansett Bay, while oyster culture collapsed. When the bay scallop population surged in Rhode Island, in 1923 the fishery managers then were surprised—tremendous amounts of bay scallops in Narragansett Bay among the bitter cold winters—not realizing of course that is exactly what the bay scallops needed. We may be in a transitioning pattern currently cold enough to return menhaden and help lobsters in eastern Connecticut, but not warm enough to increase the blue crab from its apparent retreat into habitat compressed warmer areas along the coast. If it gets warmer, blue crab populations will slowly increase, denoting perhaps trouble for the rebuilding lobster populations in eastern Connecticut. When reviewing the historical fishing records, blue crabs and lobsters do not peak at the same time. In fact, over time they show exact opposite periods of abundance in southern New England. The first clue to a habitat/fishery reversal is perhaps the presence or absence of megalops in the water column – is it blue crab or lobster? Thanks to Howard M. Weiss, Ph.D., Project Oceanology, 1084 Shennecossett Road, Groton, CT 06340, we now have a key for crustacean identification – Keys to the Larvae of Common Decapod Crustaceans (Lobsters, Crabs and Shrimp) In Long Island Sound. Following is the introduction to the key:
Introduction
“Decapod crustacean larvae are a common constituent of Long Island Sound (LIS) zooplankton. This identification guide bridges the gaps between two other currently existing manuals for the identification of these larvae in the northeast region: Sandifer (1972) for Chesapeake Bay and Rolf et al. (1985) for the Canadian Atlantic. This book includes LIS species at the northern end of their range not found in Canada, LIS species at the southern end of their range not found in Chesapeake Bay, as well as recently introduced species. Illustrations, descriptions and keys to the identification of the adults of these species can be found in Weiss (1995).” (2017 Connecticut Sea Grant, University of Connecticut, CTSG-17-09)
Tracking the megalops stages (for both lobsters and blue crabs) is perhaps one of the best ways to measure climate changes. We also need to acknowledge our seafood bias—when lobsters declined in both 1898 and 1998, it generated hundreds of articles about that decline and public support for this seafood), but when blue crab populations surged there were far fewer articles. It is the “staple” or important fisheries that command attention—codfish, halibut and of course lobsters. The decline of these fisheries as well as alewife, shad and salmon, in fact led to the United States Fish Commission founding in 1871.
Blue crabs, important in the south, did not garner the same attention here as many cold water species. When waters warmed in the 1860’s, coldwater fish populations – (especially shad) declined. It is not surprising that the delay of a decade in response—1861 to 1871—when considering the Civil War. Declines in fisheries had already garnered public policy attention; fishery managers and fishes raised the alarm bell in Connecticut years before 1867—as declines in shad, alewife and herring in the Connecticut River led to a report ordered in 1865 to investigate the decline of these anadromous fish (See Connecticut River Fyke and Shad Fisheries, 1900-1920, IMEP #21, The Blue Crab ForumTM, Fishing, Eeling, and Oystering thread, July, 17, 2014)
Sapropel and The Blue Crab
We could learn much from the blue crab in sapropel as did we learned from the eel. Both species live in and next to sapropel – organic deposits of fallen leaves, forest duff or manure – (both animal and human). Early estuarine researchers studied the bacterial role of organic matter digestion of cellulose in estuaries for oxygen loss as biological oxygen demand (bacteria) of and chemical oxygen demand, but did not link those processes as to how it impacts habitat quality.
Both Blue Crabs and eels hibernate in sapropel what most fishers call today black mayonnaise. Sapropel has two very different habitat values – in cold a sulfide limited organic compost rich in oxygen with oxygen bacteria that break down organic matter and in heat a sulfide rich deposit that is described in the historical fisheries literature as “rotten eggs” smells from “dead muds,” the result of sulfate-reducing bacteria, a marine compost with bacteria that do not need oxygen to live (See IMEP #61-A and #61-B, The Blue Crab ForumTM, posted on March 28, 2018 and April 3, 2018, Fishing, Eeling and Oystering thread). Eels live in sapropel not only as a safe hibernation habitat but also perhaps the smell of this compost by its own sulfide generation provides a dangerous smell or smoke of death that keeps larger predators away. In our Long Island Sound habitats tautog and starfish would (and have) made short work of any hibernating crabs out in the open. That already has occurred here in the 1950s and 1960s when blue crabs by the thousands tried to hibernate between Kimberly reef and Faulkners Island, an eastern rig trawler (winter flounder) operated out of Guilford Harbor by John Walston termed the area Connecticut Blue Crab graveyard (See The Blue Crab Forum™ Megalops Report, July 11, 2011 posted on the Northeast Crabbing Resources thread). Eels also benefit I believe from this smelling compost as well a slight hint of sulfide which is one of the most toxic chemicals in seawater would be enough to keep large oxygen requiring apex predators (mostly fish) away from hibernation habitats of sapropel. We know from the literature that sapropel can harm blue crabs and lobsters – from Vibrio bacterial infections of shell disease. (Blue crabs have shells with erosion holes or pits, See Blue Crabs and Marine Bacteria EC #12 posted June 2, 2016, The Blue Crab ForumTM, Environmental Conservation thread) or that the first shell disease in lobsters were caught in the New York bight area next to organic sludge deposits. In the historical literature is reference that sapropel can kill – the failure of the lobster experiment was attributed by filthy mud of Vinalhaven island Maine (See IMEP #68-A, Sapropel and Habitat Impacts to Fisheries, The Blue Crab ForumTM, posted December 12, 2018).
Sulfide poisoning of oysters in Long Island Sound or in the York River occurred in heat. It is the sulfate and sulfur reducing bacteria that cause the blue crab jubilees in heat and little energy and now perhaps the habitat trigger to the 1998 – lobster jubilee. Sapropel is a toxic habitat type in heat and why perhaps a die off. Blue crab populations are sun “brittle” they can respond quickly to temperature/chemical reactions in the habitat they spend at least four months/year. Sapropel with ammonia, alkaline pH, sulfuric acid low pH, and weather oxygen or sulfur bacteria live in it high heat (sulfides). You would expect that with all the global warming discussions that many environmental groups would rush out to talk about this dangerous substance but for a few exceptions, they have not. I believe the reason is for the past half century they have promoted all estuarine bottom types as “good” and any bottom disturbance as “bad.” When it comes to sapropel, a living marine compost, as on land nature turns this compost by energy and not a shovel or plow as we do on land but waves and tidal surges of coastal storms. Bottom disturbance is both natural and at times good/necessary to maintaining habitat quality. Blue crabs live in a habitat zone subject the most temperature and energy fluctuations, the 20 feet or less, and it here that we can see the impacts of storms and hot and cold climate cycles. That’s what makes it so difficult to predict a very hot summer sapropel may kill the megalops when setting, a cold winter sapropel can cause the sulfides to form and killing adult crabs in the hibernation period. Together with predators, and weather events can cause wide fluctuations in the population and then the catch. This is nature and not just us as represented by the blue crab fishery.
And what do we know about “our” sapropel – very little until recently I believe that reflects the last half of century of estuarine study – the focus of which was our impact upon the environment pollution and fisheries management that concentrated on catches.
You can see references in the literature about heat – such as the blue crab jubilees and in cold sulfide dead bottoms or “winterkill” but very little about nitrate to sulfate bacterial change. This bias is clearly represented in the eelgrass restoration literature – no or little discussion of soil science. Many eelgrass transplants were in sapropel with little chance of success.
When historical information is reviewed you can also see immense catches of seafood when pollution was high (such as the middle Atlantic oyster industry in the 1900s) and reverse of species in cycles of cold/energy (for example, the shad catches) govern two of the most important habitat factors and two items we know the least about. While pollution is a serious concern – the catches of shad increased in the United States in the 1950s not because of pollution abatement but because it was cold. The Clinton Harbor example presented here and at the 2006 International conference for Shellfish Restoration is a frequent one I use to illustrate habitat change (Clinton Harbor and the Great Heat).
(See CT Legislative Shoreline Taskforce Additional Documents August 6, 2012 or IMEP Newsletter #24 The Blue Crab Forum™ Fishing, Eeling and Oystering thread, Sept 03, 2014).
It is here in Clinton Harbor I was exposed to energy systems, a barrier inlet, a river and its salt marshes, the Hammonasset River. For 50 years, I have watched this system in cold and in heat and like most shallow water fishers seen the habitats change. Key to this habitat change in Clinton Harbor was the rise and fall of sapropel.
One of my first blue fishing experiences was in front of Hammonasset Beach, I was in a nine foot Brockway dingy that my bother found in 1966 – after a storm. It was cold then colder than most of the winters I can recall, sea ice would form a slush really that when sprayed formed ice walls along the beach. By June however the ice walls were gone instead bluefish were “on the beach” in shallow waters cool and remarkably clear. Large blues need oxygen to be high and in these times cool water had plenty both menhaden and blue fish were in the shallows when it first warmed.
I had seen them surrounding a small school of menhaden and in the shallows meant the chance of catching a “big blue” was very good. A pair of oars some treble hoods a fishing pole and gaff and I was off. No sooner than I snagged a bunker (menhaden) the bluefish took off. I pursued but every cast it seemed the blues moved again; I chased them for 3 miles, before I caught one – at a young age, I learned that fish could swim fast. If habitats failed, they could just swim away. Other species could not, and many times quickly enough – the lobsters and benthic crabs. After Hurricane Gloria, I learned that habitats could change just as fast.
If someone had come to me in 1988 and tell me by 2008 Black sea bass would surge, Blue crabs would become so abundant and lobsters would experience a severe dieoff, I should have believed it. But all these things did occur and were documented in the fisheries literature as happening before a century ago. That is why it is so important that we compile and maintain a long-term habitat history.
The Cycles of Seafood
We may never know exactly why Robert Roosevelt of the 4th New York Congressional district submitted a bill to create the U.S Fish Commission in 1871. We do know that a decline in commercially important fish had already occurred and the legislation was to directly address the decline in fisheries since the 1860’s. While doctors had to deal with fast fatal bacterial infections during Civil War battles, the heat had dealt a blow to New England cod fishery—one researcher had estimated that in the 1850’s, codfish in some areas declined by 90%. Whalers also found the last significant numbers now only in the colder polar regions, seeking whales far to the north and south. Connecticut’s halibut fleet had largely disappeared in the 1850’s (The Fall of New England Cold Water Fisheries, IMEP #55, Parts A and B, The Blue Crab ForumTM; Fishing, Eeling and Oystering thread, October 2015) and by 1865 was gone (See Climate Change, Habitat Stability; A Case History For The CT Halibut Fleet, 1848-1881, IMEP #54, August 20, 2015. The Blue Crab ForumTM, Fishing, Eeling and Oystering thread). But in 1872, one year after the U. S. Fish Commission legislation became law, the climate in New England turned sharply colder—bitter cold, so cold that cattle and dairy cows froze to death in unheated Connecticut barns. Entire apple orchards were frozen in valleys as temperatures fell to 36oF below zero (State of CT Board of Agriculture Report, 1875).
The 1870’s ushered in at times cold so intense, it challenges the imagination today of those that endured such cold then. But fisheries record what happened several years before—cod fish, for example, had to both grow to a size to be “catchable” and be in range of the handliner fleets in sight of shore. Adults were targeted and “lag” by 5 to 8 years into the fishery, therefore, a decline in 1865 measures reduced recruitment some five to eight years before. (These in time would be known as a year class). The concern in 1871 (expressed by legislation) reflects conditions in the present fishery or fisheries that happened in the 1860’s perhaps even earlier. The 1872 report of the newly established U.S Fish Commission was acknowledging steep declines in Cod fish (a staple fish) but also those fish that returned to streams to spawn, alewives, shad and salmon were all declining. All these fisheries have “delays” the “run” of the present year reflects those (some 3 to 7 years) spawn events before. This is termed a recruitment failure but is also a “history” of environmental factors. Low stream flows, warmer temperatures, and predator/prey interactions can greatly decrease these fisheries.
Spencer Fullerton Baird, first directory of the US Fish Commission, had already begun studies at Woods Hole, Massachusetts, in 1863. He knew that Europe had also seen a decrease in fisheries and the first culture efforts had started in Europe in the 1850’s—two decades before the U.S legislation in 1871. In 1877, Commissioner Baird gave a stern caution about concentrating too much emphasis upon man’s actions alone for the decrease in coastal fisheries. Baird’s speech at the International Commission of Fisheries held at Halifax, Nova Scotia contains this section from Paul Galtsoff History of Wood’s Hole Circular, 145, Washington, D.C., May 25, 1962:
[The Halifax Fisheries Commission came in response to treaty negotiations for fishing privileges for United States fishermen off of Canada and Newfoundland. The United Kingdom sought a payment of 5.5 million dollars in gold coin as compensation for American fishing rights. Although the commission gave a split decision (U.S objected) we still paid the 5.5 million for the fishing rights to fish in Canadian waters in pertutity).
Spencer Baird’s address 1877 To The Halifax Convention:
“Fortunately, it is believed they (the fisheries, T. Visel) are capable of remedy by proper legislation and protection, artificial propagation etc, and that we may look forward in the distant future to a very considerable return to the former, very desirable state and condition of the fisheries…the status of fish in the sea is very largely determined by the question of temperature.”
Although not mentioned here, multiple reports from ship’s logs indicated that many staple fisheries had simply moved “north” into British waters and U.S fishing vessels therefore followed them, thus the payment in gold coin for this fishing privilege. (England insisted upon gold coin, not paper currency, as payment).
About a decade later, the east coast from Georges Banks to Cape May (April, 1882), J. W. Collins estimates that 1.4 billion tilefish died in perhaps in the largest fish kill in U. S. history. In 1881, the water was extremely cold—so cold as to create perhaps an over turn of immense scale offshore, bringing colder water to the bottom so quickly that perhaps tilefish could not survive. (See “The Cold winter of 1882 New England” (1906 Weather Bureau publication) (Bulletin The States Weather Record, 1906, page 15, U. S. Weather Bureau, 1906)
From the U. S. Weather Bureau, 1906 summary of the 1880-1881 winter:
(The weather pattern resembles 2014-15 with a “vortex” of cold occurring in the west beginning in November, then moving east – T. Visel). For 153 days from Nov. 22, 1880 to April, 23, 1881, the average temperature at New Brunswick, New Jersey was 29.3 degrees. In the northern and eastern parts of the U. S., the coldest month was January (except that of 1875) and in the south only years 1872-73 had lower temperatures. In 1882, an arctic cold gripped New England, and by the 24th of January, temperatures as low as 16 to 23 below zero in southern New York. A cold wave hit the southern states on February 18th to the 20th. It was April of 1882 that J. W. Collins reports the largest fish kill in U.S history of tilefish. It would be 15 years before tilefish returned to New England waters when it began to warm again.
Sapropel and The Blue Crab
Will crabbing improve or decline—or why do we have fewer crabs this year are two questions that came in every week. Most of the blue crabbers I have met this year all mention how poor (generally) the crabbing was last year, and ask “why”? I respond that it is unclear—we really don’t know—and I believe in our area it is linked to temperature and storms. But habitat memory can be very short. Most crabbers do recall the 2008-11 blue crab seasons but the storms and cold that followed have faded into this summer’s heat. We really do not have a good habitat knowledge base (other than observation) that has a climate footing. It may seem ironic to see that in print with all of today’s climate change discussions, but it is true nonetheless. Many of today’s climate change discussions do not explain past fisheries impacts from them. Up until a few years ago many lobster fishers were unaware of the 1898 – 1905 lobster die off or the response of state and federal agencies construction of lobster hatcheries. In many climate changing fishery discussions the past has been “missed.”
In geological time, 5 years is just but second, but we do have observations from the 1800’s. In the 1870’s, cattle froze to death outside of barns, in Connecticut, entire apple orchards were destroyed (See Special Program, Report #3, The 2013 Blue Crab ForumTM, posted on May 30, 2013, The Blue Crab ForumTM, Northeast Crabbing Resources) by temperatures 30 degrees below zero. Ice was so thick in Long Island Sound that it removed entire wharfs and pilings, and damaged previously built breakwaters. In this cold, lobsters were on the beaches close to shore, bay scallops flourished in Long Island Sound—Connecticut and New York fishing fleets even landed codfish. However, after the 1870’s as waters gradually warmed into the later 1880’s, menhaden fisheries exploded; lobsters, at times, even extended into New Jersey waters. Bay scallops were abundant in Narragansett Bay. Three decades later lobsters and bay scallops were gone – replaced with blue crabs and oysters.
It was Sally Richards (Little Harbor Laboratory, Guilford, CT) who pointed to larval surveys as an indicator of future recruitment while surveying present adult populations. Most of the near shore reports come from her surveys in the 1970’s along Connecticut’s coast. Trawl net surveys of Inner White Top Rock, Guilford Harbor in 1971-72, contained large numbers of menhaden, scup, sea robins and winter flounder. The most prevalent crustacean zooplankton was the barnacle, spider crab and mysid shrimp. She raised the concept of predicting benthic populations by local larval surveys decades ago (Personal communication, T. Visel, 1980’s).
Benthic surveys can provide what has survived to nursery habitat stages—and it is natural in cold to see species at the shore with higher oxygen levels and retreat back to cooler waters in summer. Blue crabs exhibit this behavior as well—in August the shallow waters contain little oxygen (most fish kills occur here as well) and in heat over time may fail for coldwater species.
(Notes on lobster culture part 2, Richard Rathbun, U. S. Fish Commission 1886)
In reports, shallow water lobsters did fail, first even in the cooler waters to the north “on the coast of Maine the evidence of decrease are very strong, especially as regards the shallow areas, but the rapid extension of the grounds into comparatively deep waster has made the actual decrease less apparent,” and (referring to 1880 data) “about a year ago a prominent Boston dealer wrote that he was receiving large quantities of lobsters from Nova Scotia.” What was happening was lobsters were moving offshore to cooler waters, catches increased and megalops recruitment into northern areas held steady while those in southern New England fell sharply.
Maine’s catches would now rise while the southern edge of its former range lobster populations collapsed – southern New England. Although researchers looked at increased effort, increased prices and new winter fishing grounds as reasons why Maine’s lobster catch increased. Lobstering would improve in the northern Maritimes and as mentioned above in Nova Scotia.
And the Blue Crab question that largely remained off the radar – we know from several sources including US Fish and Wildlife Statistics that by 1910 Connecticut was starting to record blue crab commercial catches, and Rhode Island also and it was mostly a small boat fishery and catches not subject to landing or shipping records. This is where local State reports from Connecticut and Rhode Island are so important. The federal reports just do not have that much information about southern New England Blue Crab catches. No doubt as more “grey literature” is put on line we may be able to reconstruct a more complete picture of local conditions and or habitats that supported the blue crab then, expect with the knowledge that it reappears after long “hot periods” when lobster populations decline.
Following the blue crab catch could provide key research information regarding the chemistry of habitat changes in shallow waters, something that has been recently “missed” again. That is the rise and fall of sapropel deposits, a marine subtidal compost that builds in heat. In cold periods, it tends to disappear.
So perhaps the key to the blue crabs and the cycle of lobsters (dieoff) is the mapping of sapropels. If deposits are growing, it signifies heat, if lessening, then cold.
1) 1790 to 1815: Lobsters reported as scarce – dieoffs reported? Blue crabs?
2) 1898 to 1905: Southern CT lobster dieoff. Blue crabs surge.
3) 1998 to 2006: Southern CT lobster dieoff. Blue crabs surge.
If the continued cold persists, will the first small lobsters reappear in Central Long Island Sound as they did in 1912? If that happens, the blue crab populations of 1998 to 2010 are likely going to continue to decline – my view, T. Visel.
Appendix #1
CONNECTICUT STATE BOARD OF FISHERIES AND GAME
JUNE 1962
Hammonasset River
The Hammonasset River, rising in the town of Durham, is obstructed by a large dam creating the Hammonasset Reservoir at Route 80 in the towns of Madison and Killingworth. This reservoir is owned by the New Haven Water Company. Below the dam, the Hammonasset River has a history of populations of shad, alewives, white perch, striped bass, tomcod, and sea-run brown trout. There is one small barrier below the Hammonasset Reservoir; the abandoned dam at the old Paper Mill Pond site has practically disappeared, and no longer impounds water.
Fairly intensive study of this stream system in connection with the sea-run brown trout investigation has indicated that the new Hammonasset Reservoir has contributed to the deterioration of water quality through warming and irregular flows. These factors, plus the establishment of a warm-water fish population in the reservoir which, in turn, has encroached upon stream habitat, have eliminated evidence of natural populations of trout. The only recommendations that can be made regarding this system would be to assure for constant flows out of the reservoir and to eliminate the remnants of the abandoned dam at the old Paper Mill site. Some blasting could improve conditions for fish passage at this abandoned dam site and thus open up an additional five miles of stream for brown trout and shad.
*Rekeyed by Angela Lomanto for The Sound School
Appendix #2
The Lobster Fishery – A Special Report including Suggestions for Uniform Laws
Made To the Legislature of Massachusetts by
The Commissioners on Fisheries and Game, 1911
Comments made by R.F. Conwell during the Lobster Convention, Boston, Massachusetts- September, 1903 (Cape Cod):
“Our lobster fishermen claim they catch no short lobsters on account of the size of the traps (large rings and wide distance between the slats (lath – Tim Visel). Last year the lobster fishery on Cape Cod never was better. This year (1903 – Tim Visel).
This has been an off year owing to the abundance of crabs, which come in and covered up the bait in the pots.”
