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BlueChip
Joined: 29 Jun 2011 Posts: 177 Location: New Haven/Madison/Essex
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Posted: Mon Feb 22, 2016 11:12 am Post subject: Megalops #6 Fall Report - Tim Visel |
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The Search for Megalops
The Sound School Regional Vocational Aquaculture Center
Blue Crab Research in Long Island Sound 2015
“You Do Not Need to Be a Scientist to Report”
November 6, 2015
Tim Visel
View Megalops Reports on CTFishTalk™ Saltwater Reports Thread
Report #6, 2015
Thanks also to Connecticut Fish Talk ™ for including Megalops Reports under the Saltwater Reports thread and Dr. Matt Ogburn, for posting all Megalops Reports.
• Late summer and fall reports
• Blue Crabs holding on, a warm fall in refuge areas
• A different weather period – a habitat reversal seems possible
• Rhode Island’s Blue Crab Capital
Late Summer – Fall Reports
A series of late summer into fall reports of some good catches of 20 to 30 blue crabs were reported, but a crabbing trip can be several hours in length; most reports sent in range from 2 to 6 crabs per hour. A nice scattering of small inch crabs were reported from Branford River (before the first week of September, sulfide kill) to the Black Hall River in Old Lyme. Several offshore reports mention small crabs in Black Sea Bass but two reports mention a crab megalops that might be Jonah Crabs (Cancer borealis) not blue crabs.
Some crabbers have been following the increase in Jonah crabs in northern waters; they have surged in the commercial fishery as well. The offshore fishery for Jonah crabs has grown from 3 million pounds (1990s) to 17 million pounds (2014) currently. An Interstate Fishery Management Plan for Jonah Crab is now under construction by the Atlantic States Marine Fisheries Commission.
When I gave inshore fishing workshops at the Massachusetts Maritime Academy (1982-1990) on Cape Cod at break times outside of the cafeteria crabbers would be fishing along the Cape Cod Canal for Jonah not Blue crab; using similar box and circular traps, but for these crabbers, they preferred Jonah to Blue crabs. I have had Jonah crabs many times and they are quite good. The commercial offshore catch of Jonah crabs has increased so fast it would not be surprising to see Jonah crab megalops set in coastal bays. (Even adults if it remains cooler well may mix into former blue crab habitats). The increase in the size and scale of the Jonah crab fishery has now garnered the attention of the Atlantic Marine States Fisheries Commission; they have a management plan now available for review and comment. Jonah crabs prefer cooler waters.
Many crabbers have also reported huge increases in spider and green crabs as well (Megalops #5) and they seem to be doing better in colder temperatures. Spider crabs for example now are numerous in deeper areas of Niantic River. Reports from eastern CT from some lobster fishers (recreational and commercial) mention an increase in “clean” shell rot bacteria free small lobsters (great news for lobster fishers in the decade ahead). This also occurred about a century ago after the 1898-1905 lobster die-off. I reported on 1912 lobster fisher observations in the IMEP Report #55 and The Collapse of Cold Water Fisheries 1890-1910, Blue Crab Forum™ fishing eeling and oystering thread commenting on the increase of “shorts.”
Bay scallops have held near Mason’s Island area all summer and any offshore bay scallop populations may now move inshore this winter when it cools. On November 8th I decided to take another look at the State of Connecticut Niantic River Boat Ramp. Last spring seagulls were dropping large adults scallops on the parking lot there and were present as of June 15, 2015 (Megalops Special Report #1 2015, Sulfide Winter Kill).
The presence of such scallop shell harsh is a good indicator of what’s around seagulls don’t waste their time to drop empty shells on parking lots smashing them and exposing flesh. As soon as I pulled in the parking lot I watched on immature seagull drop and then tear into a large bay scallop. A quick look revealed by scallop shell harsh all over the parking lot – large adult shells covered by algae and double deckers crepidula shells where on many of the very fresh scallop shells. If bay scallops were still in Niantic River was answered very quickly – yes they are still there.
That happened last January – December was very warm so bay scallops movement into the bays occurred later then usual. Resurgence in Tautog (blackfish) has also occurred. So much habitat/species information has come in since our weather here has turned noticeably colder and storms frequency increased. Could this be the signs of a species reversal not seen for a century? Could be, the species to watch now for declines: striped bass, oyster recruitment and of course, blue crabs. Black Sea Bass are still showing high productive productivity, but after decades of colder temperatures they declined in the 1960s. If it returns to heat, we may see things switch back, blue crab reproduction would really increase, but the last reversal lasted from 1932 to 1972 with warmth and few storms from 1972 to 2011.
Many Striped Bass fishers have also contacted me about a dramatic decline in silversides, a significant forage base for stripers. This spring I also noticed a decline. The past three years I have noticed some habitat changes as well, tremendous quantities of eelgrass wrack torn up plants from coastal storms. Look for new patches of “clean and green eelgrass” (one of the first signs of habitat succession are grasses after forest fires on land or in shallows after hurricanes) along our coast moving into disturbed yet “cleaned” soils. Storms and temperature change often results in habitat and instability and species change. These factors can and do impact salt marsh habitats and readers interested in salt marsh ecology may find paper #7, Salt Marshes a Bacteria Battlefield Environment Conservation thread of the Blue Crab Forum of particular interest.
I appreciate all the comments not only about blue crabs but other fisheries as well. See you at the docks, “Blue Chip.”
Tim Visel
Blue Crabs Hanging in to Habitat Refuge Areas - a warm fall
Some of the best fall blue crabbing have been in coastal deep salt ponds or dredged river channels. These deep coastal areas hold the last remaining dense pockets of blue crabs. Crabbing in them has been good over the summer but most areas do not resemble catch rates of 2010 or 2011. However blue crabbing remains a fun and popular shoreline activity, some fall catches have been very good in Guilford.
During the past three decades our coast has been in warm cycle, free of strong storms until very recently and Sapropel (Black Mayonnaise) has built up in them. Once disturbed the sulfide it produces is the smoke of the oxygen “burning” of organic matter, most fish will flee these areas as terrestrial animals before a forest fire. Fishers often experience this when they disturb these Sapropel deposits while crabbing or freeing an outboard motor. Occasionally boaters will dislodge this blue/black material and the smell of hydrogen sulfide can become very strong especially on calm days with little wind. Some of the densest Sapropel deposits exist in the Pattagansett River in East Lyme at least some of the deepest deposits I have surveyed (between the railroad causeway and Fair Haven road). When Sapropel is distributed it emits a chemical smoke (sulfide and sulfuric acid) that is highly repulsive to fish and crabs, it can cause crabs to walk ashore.
One of these habitat areas is about to be dredged, the Black Hall River in Old Lyme; I prefer to term it “organic matter cleaning” as this organic compost when deep is very damaging to marine life but what about the crabs? If the dredging occurs in early fall, most crabs will move, losses should be minimal, but there will be some losses I am certain about that. Anyone who has monitored the cleaning (dredging) of a pond of organic matter (fresh water Sapropel) or stream channel will see a loss of fish, but in a few years better fish habitat conditions will exist. One of the danger signs of gathering accumulating Sapropel deposits are fish kills, such as the ones in the Black Hall River, a couple of years ago, about 1,000 small striped bass were killed, most likely if it is a quick and silent killer—sulfide was involved. These often occurred after a long cold winter (often termed winter kill) but better termed a sulfide kill. Small striped bass kills occurred in previous years here – but not as large. Fish kills can intensify as Sapropel deposits grow deeper and a series of fish kills a sign of degrading habitat quality. Although much has been written about how good these Sapropel deposits area, they are not- not in terms that enhance seafood productivity they are often in fact toxic. They contain sulfate or sulfur reducing bacteria that consume these Sapropel organic deposits – mostly the result of oak leaves in slow moving waters. (IMEP #26 and #31 Blue Crab Forum™ fishing eeling and oystering thread) Oak leaves are the most damaging, habitat wise. They contain much wax a drought protection against loosing moisture from leaf transpiration. As this marine compost builds – boaters know this as reduced channel depths and in high heat fishers report sulfide events deadly to fish and shellfishing. Very often larger Sapropel deposits will be exposed at low tides and appear green in the shallows. Sea lettuce Ulva lactuca feasts off the ammonia shed by Sapropel – sea lettuce thrives in it and some of the densest blankets of sea lettuce can be found in or near Sapropel deposits.
While watching a dredging project is at times visually disturbing (and often highlighted as always negative in some environmental media) the outcome years later is rarely reported. While canals and canal builders have long struggled with terrestrial leaf fall and eventually Sapropel formulation (fresh water Sapropel is frequently brown with the consistency of peanut butter) rivers and creeks also each year obtain huge quantities of leaf matter – especially in or during tropical rains. Deposits can become several feet deep and fishers occasionally notice large accumulations of oak leaf stems in quiet back waters, the remains of organic matter reduction. These leaf stems are tougher and take layer to digest by bacteria. A quick stroke with a paddle or oar can send thousands of these stems in motion – as I have observed this many times (blue crabbers may have see these stems as well) in shallow waters.
How will this “energy” impact blue crabs? From what I have been able to determine from North Cove in Old Saybrook which was dredged for a marine basin in the 1950s. Extensive Sapropel deposits still exist to the north and east near the now abandoned railroad causeway. The dredged area however provided a deep hole and has been one of the best blue crab over wintering locations I have reported on since 2010. Menhaden also hold up in the basin as well, and provides good Striper Bass fishing (personal experiences included) South Cove has not been dredged and blue crabs can be found here but nothing like the density I have observed in North Cove. These shallow areas most likely freeze up. The clearing/cleaning of Sapropel remains controversial but careful post dredging monitoring should occur and for the Black Hall Project (my view). Fishing often improves after sulfide rich organic deposits are removed. A special section about coastal energy and blue crab habitats is found in Megalops special report #3. Rhode Island’s Blue Crab Capitol – Pt Judith Salt Pond – when inlets were closed they were frequently reopened.
Although the account is nearly one century old, it describes the research of Dr. G. W. Field and his observations of both organic matter and bacteria. One of his suggestions to minimize this habitat impact was to enlarge coastal barrier outlets called breaching to let more sea water exchange and flush out organics, greater currents of seawater did allow this but also allowed more saline predators to enter as well. This is just a way to increase “energy” and is mentioned in small scale fisheries all along the coast.
One of the things that Oyster River residents in Old Saybrook noticed when about three feet of Sapropel was removed (1981-83) not by dredging but oystering was the river was “reborn”. Winter flounder and blue crabs returned; sulfide smells for a time subsided in the immediate area. Colder sea water contains more oxygen and Sapropel in low oxygen and heat emits toxic substances, dredging at times removes all organic deposits down to the “black sands” and if these marine soils are rinsed of organic acids they now can sustain clam sets, beneficial for winter flounder especially small ones.
Sapropel deposits in CT have also suffocated many such soft shell clam beds (Niantic River). On occasion dredging has uncovered long ago buried “relic” oyster reefs, habitat histories of previous habitat reversals. Unfortunately few dredge operations take notice or report such previous habitat conditions, clam or oyster shell deposits, bottom sands or pebbles or just Sapropel. It just comes up as “dredged material” and that is a missed habitat history opportunity especially for marine soil sulfide and pH data. One dredging project in the lower East River, Guilford, CT in the 1980s that was monitored (and reshelled with oyster shell clutch) with a University of Connecticut Dive Team and obtained a very good oyster set as winter flounder soon returned; I will put that report up on the Fishing Eeling and Oystering Thread (Blue Crab Forum™) shortly.
In 1985, I asked the Army Corps of Engineers to investigate the concept of post dredging use of oyster shell to stabilize estuaries pH and jump start oyster/clam beds as a way to help other fish species. The shell placement is like terrestrial lime; it reduces the sulfuric acids of Sapropel and helping seed oysters (if sufficient larval forms are present) or assists the setting of clams – both soft shell (steamer) and the hard shell Quahog. Blue crabs especially the small ones find food and cover in these shelly habitats, something that has been extensively written up in the literature.
We need to more closely follow our inshore dredging projects although at times they appear to be very bad – most in a few years support productive and valuable crab, shellfish and finfish habitats. Removing Sapropel that purges ammonia and sulfides will help marine life that is often the foundation for most of our inshore fisheries. That is why we see so much habitat change after hurricanes (see IMEP #11 Historic Climate Impacts to Fisheries). Fishing Eeling and Oystering Thread (Blue Crab Forum™).
One of the most important case histories of Sapropel appears to be the New York Long Island Duck Farm Industry. Here in times of little concern and very cold temperatures duck manure was washed or discharged into local waterways. In time, these deposits putrefied, became Sapropel and discharged large amounts of hydrogen sulfide. In the 1970s, Niantic Bay CT residents learned not to park cars under streetlights as sulfur fog rising off The Niantic River and condensation on street lamp bulbs turned them into a “sulfuric acid drip” ruining car finishes below. Last month The Tampa Bay Times reported that a yellow fog – described as a “cloud of sulfur” spread off the Flamingo Visitor Center “leaving behind a stinky stain call yellow fog.” (Dying Sea Grass Yellow Fog Signal trouble for Florida Bay – Jenny Staleovich Miami Herald Oct 2, 2015) Florida is approving dredging projects to remove sapropel described as “black mayonnaise” that in some spots is more than 10 feet deep. (Florida Today June 8, 2015 Jim Waymer). The muck the article describes “produces noxious chemical compounds, such as hydrogen sulfide that creates the lagoon occasional rotten egg smell.”
* Rhode Island Blue Crab Capital –Pt. Judith Salt Pond
Many blue crab crabbers were surprised this blue crab season as it was not like the previous years. One of the example places that I have been able to focus on is Pt. Judith Pond in Narragansett, Rhode Island (and one mentioned in The Search for Megalops special report #3 – 2015).
This area is unique also to a “first” Maine Experiment Station – part of the University of Rhode Island Agriculture Experiment Station – the first built by a Land Grant University (See an excellent write up of this effort in a paper titled proximity to sea coast G. W. Field and The Marine Laboratory at Pt. Judith Pond by C. Leah Devlin and P.J. Capelotti). Built and operated 1896 to 1900 on Great Salt Pond as it was once known. A very detailed review of its operation – 1896 to 1900 is available and to some extent can answer many blue crab habitat questions. It was in operation at a key period the collapse of New England’s cold water fisheries (IMEP #55). By 1895, a series of mild winters and very hot summers had taken its toll and in 1895, a huge fish kill occurred here, most likely accompanied by the smell of sulfur in the salt pond once known as the Great Salt Pond. The experiment station on Buttonwood Point was built quickly and no doubt sought to answer resource questions. The laboratory director Dr. G. W. field most likely had no idea of the Great heat or the extent of the resource collapse soon to happen – 1898 Narragansett Bay suffered a lobster die off. By 1906 Rhode Island Fishery managers were shocked by the catch of Tarpon, but they noticed something else an unexplained and perplexing rise in Blue Crabs – called the Blue Crab question. In a 1906 report Rhode Island Officials commented on the Wickford Lobster Hatchery “Your Commission’s (lobster) work has attracted the attention of those interested in promoting the fisheries’ interests in all parts of the world.” Indeed it did.
By the late teens, lobsters were in recovery in eastern CT and Rhode Island and some bitter cold winters 1922-1924 would return the bay scallops to Narragansett Bay - that also shocked fishery managers. However, the return of the bay scallops, lobsters and even the Quahogs would mean the end of blue crabs, oyster production and the occasional Tarpon. The Great Heat was coming to a close- and a species habitat reversal of unprecedented scale was occurring. It was getting colder and winter and summer storms more powerful. The last large blue crab populations would leave Pt. Judith Salt pond in the 1940s and when Charles Beebe purchased a retirement home on the west shore of Pt Judith Pond (one of my mentors and former Madison employer); he would welcome me with some local history, it seems at one time Great Salt Pond was known as Rhode Island’s Blue Crab Capital” – he would talk about it – having met some Pt. Judith pond residents no doubt (1970s), except now it seems he was being truthful- and from what I have found out, that statement was correct. Shortly after the cold water fisheries crashed in 1902 blue crabs became abundant and by 1906 had caught the attention of Rhode Island Fishery managers in 1906 report and referring to a new operating lobster hatchery in Wick ford, Rhode Island mentioned the increase in blue crabs. On page 16 of the introduction this change is mentioned. “Your commission believes that, as the lobster experiments are now on a firm foundation attention should be paid to the crab question, which in the future is destined to become more and more important.” By 1912 Blue Crabs flourished in Rhode Island waters.
The 1895 fish kill and the 1898 lobster die off however have been obscured by a bias of environmental protection (from us) after around 1970s. At that time, fisheries history as it related to environmental conditions or climate cycles was largely forgotten or minimized to such an extent it was a misrepresentation. From the colonial period on inlets when closed were reopened to preserve coastal fisheries.
[By 1895 for example the “breached” breaches were periodic as describing a break or “breach way” as to open or unblock a castle wall as it was frequently a bar or wall of sand cast ashore by a storm blocking tidal exchange thus creating a need for a breach”]
Instead in later fisheries articles a greater emphasis upon human impacts would appear in the modern literature repeated vigorously, thus assigning largely fish and shellfish declines to human negative interactions as seafood declines and reduction of those some human actions into seafood increases. This of course has problems when different species reverse in the same habitat profile and then again such as lobsters and blue crabs.
{My fisheries history research has identified such four reversals as largely the result of climate cycles, Pt. Judith Salt Pond has a good fisheries history because it’s inshore fisheries were so large and the studies of G. W. Field (who went on to study sediment soils in aquaculture) were during a key period that supported inshore fisheries were those that were protected from huge energy, but still contained sufficient ocean exchanges – shallow yet saline. These areas give us the best habitat examples of influence both from the land and the shallow heat sink during climate cycles. In a way the predict for us what a warming climate will mean to fisheries. It is a combination of factors many of which we have little control and why we must abandon “snapshot” ecology so prevalent after 1972}.
In the warming of the 1890s sand tended to accumulate close to shore, warm water was less dense, less erosive and storms tended to more these offshore sand bars ashore – beaches during this period actually could buildup and this extra sand soon found its way into barrier beach inlets closing them (some would say choking) off tidal seawater exchanges during now “warm” Nor’easters. This is the time that Pt. Judith’s pond inlet was filled about a mile east of the current permanent breachway.
Waters warmed and oxygen deficiency occurred and gave rise to the sulfide smells and “black water deaths” so prevalent during this period. The results of several years of heat – and reduced tidal flows – organic matter built up resulting in fish kills and die-offs, Dr. Field soon noticed as fishers did also, the damage impacts of organic matter from land was at times tremendous.
After the permanent breach was established in 1910, Pt. Judith Pond had a surge in blue crabs for awhile it seems it was Rhode Island’s Blue Crab capital, resembling in a small way the freshwater/salt water exchanges of a very small Chesapeake Bay – warm- seawater exchanges and enough fresh water to keep the most serious blue crab predators at low levels. In the warm water as lobsters declined blue crab’s surged. Jeffries in 1966 reports on the Rhode Island Blue Crab Fishery, as “Abundance of the blue crab Callinectes, sapidus, in 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” Chesapeake Science Sept 1966, Vol 7, #3 page 164.
Although most Rhode Island fishery resource reference materials blame pollution and coastal development for the decline of the blue crab (pre 1998) those views contain a bias that places a tremendous responsibility upon seafood abundance to human factors. Instead the exclusion of climate cycles which is often an important factor to seafood cycles occurred. We must look to climate cycles not human activities for the decline of cold water fishers after 1890 and the increase after 1940. If one was to follow this philosophy then pollution and heat with low oxygen conditions were the largest factors as human settlement did not abandon coastal communities. Oyster setting, Sea Bass reproductive capacity and the Blue Crab all benefited from a gradual warming post 1972. Lobsters, bay Scallops and Winter Flounder all declined post 1972.
The current Blue Crab decline may signal another climate cycle as eastern CT lobster fishers have already noticed an increase in “short” lobsters. Blue crabs will be here for a while, as they have always been, but if the cold cycle continues, they will decline as they did a century ago.
Fishery managers often miss the decline, as bay scallop fisheries improved in coastal coves along the Buzzards Bay shores in Massachusetts in the 1960s Blue Crab abundance fell.
A Westport River report by the State of Massachusetts 1967 also mentions this decline.
“The blue claw crab is a species which were formerly abundant in the south shore of Massachusetts but has been declining in numbers for at least the last decade. Such decline has also been observed in waters south of Massachusetts. Jeffries (1966) noted that the blue crab began to decline in Rhode Island in the mid-1930’s and that by 1938 they had diminished to the point that it was no longer profitable to fish for them commercially. The cause of the decline of this crab in our waters in unknown. Many fishermen along the shore have expressed the belief that the loss of blue claw crabs also fiddler crabs (Uca spp.) is due to the careless use of pesticides in coastal areas. While it is certainly possible that pesticides have had a detrimental effect upon crab populations no conclusive evidence has been documented in this regards. A study of the Marine Resources of the Westport River is the seventh in a series of monographs initiated by the Division of Marine Fisheries in 1963. These reports relate the extent and value of the marine resources of the major bays and estuaries in Massachusetts.”
* A Habitat Reversal – A Different Weather Period?
Since Megalops #5 was posted, several crabbers from other states have commented: the deep salt ponds dredged channels and deep river bends hold the most significant remaining blue crab populations. The exception it seems if these deep spots held new or larger amounts of leaves. These areas from habitat descriptions may have become Sapropelic, smells of sulfur and having a black “greasy mud”. Crabbing in these areas has been poor and often absent of crabs and from some reports absent of any life. (Blue crab Forum ™ Environment and Conservation #6). Salt ponds close to the coast, those dredged areas such as North a cove in Old Saybrook, or salt ponds with sandy bottoms and not subject to leaf fall with good flushing held many more crabs. Cooler waters this spring held more oxygen and favored green crabs (even at times spider crabs) along the shore. The cold contributed to one of the longest hibernation periods. 48 degrees F to 48 degrees F for many years - 156 days (approx) which is a month longer than some of the most generous food supply estimates of 90 to 120 days blue crabs can go without food. Blue crabs that settled into deep holes held the warm water the longest last fall but would need good tidal flushing to keep sulfides below killing levels. Thus these crabs in these pockets did not starve or get winter killed by sulfide. That is why the first catches come from these near coastal areas, salt ponds and rivers that empty into more saline waters. In these rivers it was the deep bend (holes) that held the crabs, other rivers those further from salt water wedge and heavily impacted by leaves and freshwater held few, if any blue crabs. The last good blue crabbing holes last summer became the first good crabbing spots this spring-- that is why.
Even during the very cold and stormy 1950s, and 1960s, there was always a few good blue crabbing spots on Cape Cod in the salt ponds. This type of habitat is a type of blue crab habitat refuge an area that ices over the last and first opens up. They depend upon inlet seawater exchanges and even here a shorter 48 degree to 48 degree F period than most brackish water that iced up heavily last winter. We had the opposite occur in 2010 to 2012; it got so hot that oxygen levels dropped and crabs went to these deeper areas for colder water, as it was the last to heat up. (Megalops reports #7 August 9, 2012). Crabs often head to these areas in the fall as they are the last to cool down.
Blue crabbers are the ones who notice these temperature habitat conditions, close to shore with waters that heat up fast and cool slowly; some late falls have been especially good blue crab years (Megalops #9 Sept 18, 2013). In April 17th, 2012 blue crabs had already left winter hibernation holes to feed in the shallows (Megalops #2, April 23rd 2012). This year it was mid July, 90 days later. A shift of this magnitude has been devastating to our New England Blue Crab population. If the cold continues we may soon see other species decline as well: striped bass, forage seems to be the most suspected now silversides. Some herring runs this spring were suspected of having a sulfide block as spring melt water under ice can dislodge buried organic deposits (mostly leaf rot) and purging/wash sulfides into the water just after a heavy rain. If it remains cold, we may see the “ice fish” rainbow smelt return. After our streams are cleared of these organic deposits buildup during decades of “high heat, heavy leaf falls and few storms. For those who watch the weather, a strong polar vortex last year (after Dec 20th) ushered in some very cold temperatures; New England while on the west side (west of the Mississippi, allowed temperatures to rise and be drier. I thought we were in for a mild winter until late December when a strong negative NAO opened the pathway for arctic air to sink far south bringing in the coldest February for many areas cities since the 1870s, [from many areas formal temperature record keeping began in 1875, a response to the severe cold that people thought the ice age was returning). So they missed the exceptionally cold winter of 1872-1873 when almost all of Connecticut’s apple orchards were wiped out by temperatures that sunk 10 -30 degrees below zero for days. It has been extremely cold in Connecticut and not so long ago.
Last November, at first the polar vortex had its sights on the mid west, and the northern mid western states were hard hit (Casper Wyoming fell to 27 degrees below zero Chris Bart Weather Channel historian) on November 12th the cold moved into central USA Nov 20th 2014 now as the storm track also moved to the east and set up on the eastern wall of the warm Gulf Stream about January 10th 2015- low pressure systems deflected south by this cold dense air tended to be below the usual Alberta Clipper storm track and emerged over the southern Atlantic helping to form a secondary pressure low over warm waters off North Carolinas’s Coast. We now know that as winter storm Juno. (Also called the great 2015 North American Blizzard). This Nor’easter brought a snowfall total of 30 inches to Putnam and Thompson CT and last winter’s ice melt from it lasted for weeks.
The storm track does have much to do with our ice melt duration, a more westerly storm track brings the Hudson Valley lows which in the past moves into the Catskills drawing up warm Gulf Stream moist warmer air and mild temperatures then sharp north westerly gales that follow. These storms bring heavy rains then very cold notably dry gales into the 1960s. A typical Northeastern storm track in which it is located 100 miles east of Nantucket is next to the Gulf Stream. The Gulf stream only being about 60 miles wide about 300 miles southeast of Nantucket, moisture is drawn over New England. A colder air mass colliding with the warm air can intensify these storms, sometimes very rapidly as in the case of the January 2015, Nor’easter (Juno). A shift in the storm track further east and the moisture is not able to be drawn in – known as “the dry Nor’easters” were far out to sea with cold winds so dry in New England they would at times evaporate snow. (This condition often appears in historical records as being to cold to snow). All Nor’easters were feared by mariners and named many believe for the north – northeast wind direction which told of low pressure in the southeast quadrant. Long known for the destructive capacity to maritime interests both ships and wharfs, they continue to be the most feared in the northeast Atlantic. It was Clint Hammond on the Cape that recorded them- their strength and wind duration here on Monomoy – Cape Cod. Mr. Hammond watched as they not only changed the shoreline; they also changed the sub tidal habitats. We are just now beginning to understand these temperature and energy cycles impacts upon fish and shellfish habitats, perhaps the first susceptible species in our region is the blue crab.
What is Ahead?
The winter storm track has yet to setup. On October 2nd the NAO was a negative 2.2 and continues to drop. If that continues the Arctic Polar Vortex will be open to cold Canadian Polar air, the storm track determines if Northeasters can tap into the gulf stream warm air – the storm track is not stable; it keeps shifting. During the winter of 2015 the Nor’easter storm track crossed 5 times in the same area east of Nantucket.
As the southern waters continues to absorb heat, and deliver it to us in form the manner of the Gulf Stream, look for the difference of cold dry air to next warm air to intensity these coastal lows. Will we be on the dry side, low pressure systems of the eastern gulf stream wall or inside the eastern wall is yet to be determined.
No Large Megalops Set Reported This Year
In the middle of July came several reports of 1 inch crabs in Clinton and late August these reports became generalized from North Cove, Old Saybrook to the Branford River, several crabbers reported inch crabs; certainly a good sign but nowhere near the megalops sets in 2010 or 2011. These crabs most likely arrived in late May and settled into shelly areas (Sapropel tends to be very basic at the surface and acidic just below). After our spring storms several areas were reported to be “clean” and waters clear. You could see the bottom. I had an example of this several years ago in Branford.
2008 Branford River trip with my son Willard- hundreds of bunker (Menhaden) were in the process of dying; it was hot and the Branford River was a chocolate brown from brown algae (many bunker still in the process of circulating on top). We were blue fishing and hit a major hot water die-off. Looking to get to deeper water (and more oxygen) we cut across the “gut” as I used to call it behind Kelsey island to the Farm River. About half way, Willard yelled out. He could see the bottom. I looked over and below thousands of oysters had filtered the water, it was crystal clear and over the bottom roamed thousands of inch to 2 inch blue crabs. [If anyone has ever seen this it was dramatic; it was 10 feet deep and you could see this oyster reef was just abundant with blue crabs. Crabs must find this shelly bottom more advantageous most, that has been my experiences in shallow shelly habitats.
I was involved in some 3rd and 4th grade window aquarium projects in Madison public schools. I would place 10 or so adult oysters in a 10 gallon aquarium and a second 10 gallon aquarium became an algal grow out system on a window sill. A pure algal culture was obtained 10 ounces from the Milford NOAA – Aquaculture lab and a quick few drops - [Paula Daddio, an aquaculture science teacher had a similar experience with oyster spat, an aquarium quickly cleared as oyster filtered the food; it is remarkable to watch] into seasoned salt water plus a tablespoon of bulb fertilizer and sunlight and the second aquarium in a few days became a lime green, algal food for the oysters. Students would dip a cup of two into the oyster tank and watch oysters open up and filter and in a few hours the tank was clear. Oysters have tremendous filter capacity – something that has been in the news of late.
This teacher, Mary Paffrath of Madison Public Schools then did share up after a funny story regarding this class project. Apparently the only place the Algal culture concentrate (glass jar) could be stored (it can last a year) and kept cool was in the teachers refrigerator and you guessed it…someone mistook for a soda and took a taste. A note attached to the jar read something like “Whoever bought this it has gone bad.”
Some similar experiments in Massachusetts would strain the algae and later the shell would show color. In addition to clearing the filtering of seawater bivalve shell helps modify acidic conditions; this is important in lower rivers as rain water is acidic and can carry tannic acid from leaf fall into these waters. The amount of small blue crabs in shelly areas has made me believe it is a preferred habitat for the Megalops stage as well.
A cold winter would serve to “clear” shelly areas but lower temperatures would negatively impact our remaining blue crab populations. A warm winter would allow more organic matter to cover subtidal areas but higher temperatures enhance habitat quality in those still free of organics. Another cold winter historically has lowered Blue Crab populations.
Thanks for all the reports this blue crab season.
I will try to put out an early look for the next blue crab season in January.
I appreciate all the comments and reports tim.visel@new-haven.k12.ct.us |
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