The Search for Megalops – The 2022 Crab Year – March 2023

[BlueChip]

The Search for Megalops – The 2022 Crab Year – March 2023
"You Don't Need to Be a Scientist to Report"
View our Megalops Reports on The Blue Crab ForumTM
Northeast Crabbing Resources Thread
March 1, 2023
Viewpoint of Tim Visel – no other agency or organization

•   Thank you for all the positive comments
        Tim Visel Retires from ASTE Education
•   An Interesting Blue Crab Year 2022
•   Nature's Catch – Blue Crab Predators
•   Massachusetts Report Details "What is Black Mayonnaise?"
•   Lobster Settlement (Megalops) shows Decline in Maine

In 2008, my son Willard took an interest in blue crabbing and we watched some people crabbing off the docks in Essex.  I had always thought that perhaps the Connecticut River was too fresh to allow crabs this far up river.  I was wrong and his interest and crab catches made me re-examine this belief.  That is how The Search for Megalops got started.  Willard and his friend William Schneider caught some huge blue crabs off the Essex town dock.  The early posts frequently mention Willard's catches and how to minimize crab mortality in buckets.

I have learned a tremendous amount about blue crabs from reports on The Blue Crab ForumTM.  This website is a fantastic opportunity to learn and exchange information about crabbing and other shore fisheries.  Many Connecticut blue crabbers post reports and information under Northeast Crabbing.  The support of The Blue Crab ForumTM managers is greatly appreciated.

Finally, after 32 years with high school aquaculture programs, I retired from The Sound School as of June 30th.  I still plan to continue blue crab and lobster studies that include habitat quality and the impact of climate upon inshore commercial and recreational fisheries, and I will post short reports when I can.
Many reports are on The Blue Crab ForumTM under three threads: Blue Crab reports – The Search for Megalops, look under New England Crabbing – crabbing resources; Marine Bacteria and Nitrogen under Environment/Conservation; and Eeling, Oystering and Fishing thread for Habitat History reports for many fisheries (about 200,000 views to date). 

I have not sent out to the general mail list since before Covid-19 restrictions were put in place but want to thank all those who had questions, provided comments and information, and finally to the staff and students at The Sound School.  Thanks also to blue crabbers on The Blue Crab ForumTM and the people who made these newsletters or posts possible, including Trish Russell, Taylor Samuels, Alicia Cook, Alex Ramirez, Susan Weber, Angela Lomanto, Giancarlo Lomanto, Steve Joseph, Jayleen Disla, Victor Campanile and Steven Kotch, Jr.  A few years ago, I went crabbing with Chris Bevans, who I used to crab with in Madison and caught a huge crab (See May 10, 2020 report).  I had planned to send this notice to the Megalops list in the middle of June 2022 but between packing up my office and the end of a school year, time simply ran out.

Thanks to all the email reporters who made "The Search for Megalops" possible.  I do plan to send out a few reports during the 2023 blue crab season as I continue to follow megalops patterns in our changing climate.

See you at the docks!
Blue Chip - Tim Visel

An Interesting Blue Crab Year – The 2022 Season

We had three conditions last season – drought, mild winter and heavy rain.  I missed most of the crab season due to Covid and RSV but was able to visit some of my usual crab spots in late summer.  We had, for the first time, three types of crabs – the rusty crabs that live in river habitat, yellow face crabs whose winter habitats can have some sulfur bacterial stains, and "white belly" crabs that live mostly in saltwater environments.  It was a good year, a slow start but deep water catches ranged in the 15 to 20 crabs per hour.  Shallow water was 5 to 10 crabs per hour.  Crab Cove at the bottom of Mystic River is a tremendous overwintering habitat as is the mouth of our major rivers.  These areas tend to produce the yellow face crabs and can be driven out of rivers by excess heat.  A warm open winter tends to reduce mortality of these crabs, torpid in areas with little sulfide and tend to have little staining on shells, which have brilliant white and vivid blue claws.  In colder winters, the "rusty crab" dominates the catches (personal observations, T. Visel).  In mild times, short hibernation, dormancy and less severe winter storms, "white belly" crabs survive in greater numbers.  This is seen as a greater distribution of the catch.  An early large percentage of white belly crabs means less winter kill.  White belly crabs are less dense meat wise than rusty crab – that is because they have recently shed.

Crabbers, a few years ago, may have noticed that female crabs tended to have large, white belly crabs for doublers – they tend to move towards saltwater as the season progressed.  Rusty crabs have brown coloration and may not shed in two or more seasons.  They are the river crabs and hard shell, packed with meat.  I compared picking meat and a small just legal rusty crab had as much as a 7-inch white belly crab.  A mild winter usually is better for all three habitats.  With these observations, the catches in the bucket can tell which habitats, perhaps, did better.  Rusty crabs can survive in deep holes even in the harsh winters.  Deep holes have warmer bottom waters perhaps shortening the hibernation period.

Yellow face crabs are in the middle, a better habitat except in heat, sulfide waters low in oxygen can drive the crabs out, changing the percentage of yellow face crabs in catches as what happened in 2011 when waves of "yellow face" crabs moved east.  Here catches that were primarily rusty changed quickly as yellow face crabs moved to the east after massive heavy rains.  Crabbers reported no yellow face coloration until they swarmed the baits.
A large percentage of white belly crabs is a great sign that shallow water winter hibernation period was short (dormancy) and did not build up lethal amounts of sulfide – no ice and few storms.

We also have experienced a dramatic drop in the population of starfish after the year 2000.  This is a major blue crab predator and a paper by Peter J. Auster and Robert E. DeGoursey off the Mystic River had scuba photographs of a blue crab being attacked by 19 starfish.  There are earlier reports by John Walston of Guilford, who operated a dragger out of Guilford Harbor for winter flounder.  Mr. Walston, while operating his trawl net, brought up blue crabs surrounded by starfish.  In fact, he termed the areas around Kimberly Reef as Connecticut's "Blue Crab Graveyard."  Thus, a major predator is now absent and starfish remain scarce in some areas.  Overall, catches were unpredictable and governed by depth as waters warmed.  The Essex Town Dock, a popular blue fishing dock, was an example of this.  At times, the end of the dock had 4 lines with over 15 crabs per hour at high tide, while crabbers at the shallow end struggled to catch a few crabs (personal observations, T. Visel).

Clinton Harbor (lower region) held, at times, large quantities of small blue crabs but few legal sized at mid-summer.  I think that because of the lack of rainfall larger crabs may have moved up river.  (June 3rd to July 3rd only 1.5 inches of rain).  Another reason is that bottom water temperatures at Essex Island approached 85oF on August 1st – close to where crabs rest in low oxygen conditions.  According to USGS Data Records Monitor, the surface water on July 20th was only at oxygen levels of 4 mg/Liter of water – limiting for many fish species (for reference in early April with cooler water, the level was 14 mg/L or three times plus as much).  Slightly deeper water is cooler on very hot days and it may be the anoxic (low O2) waters for the catch differences.
I think that we have had very little winter kill this year.  I see water temperatures hovering around 40oF with activity beginning at 47oF.  So, we may see crabs moving about mid-April, similar to 2012 when people were catching crabs before the official season opened May 1st.   Crabbers started sending me catch reports on April 17th.  Since 2012, our waters have cooled and winters highly variable – cold and snow filled and then mild with little ice – signs of a negative NAO.  Our news station in our region has started to mention a negative NAO in weather forecasts.

Nature's Catch – Predator Populations Change

One of the issues surrounding fisheries management today is we tend to ignore the landings (catch) of nature.  This can be seen in the review of our fisheries, which tend to recognize only our "catch."  The basic mistake is that when a species is abundant, it is assumed to be always so – that only our catch could diminish the resource.  This was explained to me by John "Clint" Hammond on Cape Cod as represented by a series of natural conditions described by "clocks."  A large reproducing population was guided by natural advantages or constraints.  This was evidenced by the dramatic downturn in silversides after the very cold winter of 2013-14 and 2014-15.  Striped bass fishers contacted me at The Sound School concerned about the decline in silversides.  In 2016 during a student field trip to Hammonasset State Park (blue fishing), we encountered Jacques Pepin of Madison, trying to seine silversides for a white bait cooking show.  He had only a few small silversides.  Three years prior, he caught a pail in just two short seines (See IMEP #84-A: Striped Bass Starve in 1938, posted February 28, 2021, The Blue Crab ForumTM Fishing, Eeling and Oystering thread).  Yes, for those thinking about Atlantic silversides for dinner, they are edible, in fact, considered a delicacy in Europe.  Jacques Pepin has demonstrated preparing and cooking "white bait" on his TV shows on Connecticut Public Television (See Jacques' Way, The Hartford Courant, April 11, 2007).  Several videos by Jacques Pepin detail "white bait" pound for pound (very little waste) on one of his favorite dishes "La Petite Friture" online.  With some warmer winters, silversides have slowly recovered.  A shift in climate can have severe impacts upon populations, a loss of forage, increase of predators, biological limits or reduced habitat.  Silversides, for example, are killed by sudden, severe cold snaps.  A sudden drop in forage leaves predators that needed them vulnerable to starvation.  It is here that nature takes the catch from us, either by biological factors or simply not enough food.  We are experiencing something similar with the surge of Black Sea Bass - both consuming small blue crabs and consuming so much forage, these fish are stunting.  Other species suffer as this huge increase in Black Sea Bass acts more like locusts consuming and moving on.  In the fall of 2013, a megalops' reporter, Alison Varian (late of Guilford) reported on October 16th that "A group of us were fishing for black sea bass in 90 feet of water off Madison, the fish were spitting up thousands of small blue crabs."  One sign of forage shortage is that fish stunt and becoming sexually mature at shorter lengths.

Massachusetts Report Details Black Mayonnaise

It is the sticky, smelly muck that has long been part of blue crabbing from the shore.  Many crabbers, no doubt, have experienced this organic ooze.  While shore crabbing, many crabbers might step into this deep marine organic compost – a loose, sticky ooze.  Few papers explain what it is.  Blue crabs survive in the shallows bays, coves and marshes – the same habitats in which this organic compost can form.  The formation of this organic compost in low oxygen is a sapropel – the bacterial action of rotting (decomposing) organic matter with sulfate-reducing bacteria.  They don't need dissolved oxygen; they use the oxygen bound in the compound sulfate.  Crabbers can recognize this material as black (mono iron sulfides), and when disturbed, the smell of rotten eggs (hydrogen sulfide) (this compost will stain your hands).  In hot weather, black mayonnaise becomes toxic.  The study for the Town of Wellfleet titled "Black Mayonnaise, What Is It and Where Does It Come From?" is on the internet.  In Wellfleet Harbor, 8 to 12 feet of this compost has collected in just a few years. 
A century ago, farmers in coastal New England harvested this sapropel as soil nourishment – after leaving it for several months, letting the salt and sulfur acids drain away.  It was often limed or mixed with bivalve shell to neutralize any remaining sulfuric acid.  The high percentage of organic matter was seen as replacing carbon and feeding bacteria that released nitrogen.  It was called mussel mud or harbor mud during the 1900's.  Its collection and use of this marine compost by William Foote of Guilford, CT (1883) is found in IMEP #68-A: Sapropel and Habitat Impacts to Fisheries 1800's to 1900's, posted December 12, 2018, The Blue Crab ForumTM (We have records about the use of marine compost dating back to the 1780's from A Hint To The Farmers – The American Museum – On the Use of Mud as Manure, Vol. III, No. 1, 1788, pg. 114).

This harvest of marine mud (mussel mud) continued north of us until 1983.  However, in Europe, sapropel fertilizer has grown in importance and provides a huge market need not only to replace carbon in the terrestrial soils but also as a way to replace acid rain leached metals.  Other uses include heavy metal cleanup as this material has the ability to complex heavy metals.  EPA, at one time, experimented with sulfate-reducing bacteria in cow manure to clean up metal ions from mine waste water.  The longer that sapropel exists, the more it can soak up metal ions.  This is a natural ore building process described in EC #19-A: The Chemistry of the Sulfur Cycle, posted October 29, 2020, The Blue Crab ForumTM Environment Conservation thread. 
More and more research is appearing online (mostly from overseas) about how this marine compost in high heat degrades fish and shellfish habitats.  One of the research areas is the presence of cysts and disease-causing spores buried in sapropel.  These spores and cysts are also found in the intestinal tracts of marine worms that live in this marine compost.  New York research indicates that more cysts are buried in deposits at the portions of coves and bays that could be termed low energy – and not subject to wave or storm energy except in the coldest of winters.  The Massachusetts Wellfleet report added important information to this Black Mayonnaise – sapropel discussion - my view, T. Visel. 

Maine Lobster Settlement Index Shows Continued Decline

For many years, Maine has surveyed the post-megalops stage for the lobster.  It is referred to as the lobster settlement index from the Wahle Lab The American Lobster Settlement Index (ALSI) and is found on the internet.  This study looks at where and when stage 4 lobsters settle to the bottom and begin to grow into a legal fishery size 7 to 8 years (used to be 9 to 12 years) later.  During this time, they are subjected to tremendous predation and natural events, such as severe storms.  The recruitment index is used to forecast lobster populations down the road.  In the fisheries literature, it is often reflected as the year class recruitment or YOY – young of the year.  The concept being a low or poor year class will impact the fishery years later as our catch.  A drop in the settlement index is a concern for Maine as its lobster catch has soared when cod fish, a major predator of small lobsters, declined in the Gulf of Maine.  As the climate warmed in the 1990's, Maine's lobster catch in 2016 rose to 132 million lbs. but declined to 98 million lbs. in 2022.  In 1955 in the coldest segment of the past century, Maine's catch was about 20 million lbs., average 1948 to 1960 was 21.1 million lbs. (See Commercial Fisheries Review, Sept. 1961, Washington, DC, Vol. 23, No. 9, "Some Factors Influencing Maine Lobster Landings" by Robert L. Dow).  In this article on pg. 7, Dow suggests the following:

"Production data suggests the probability of cyclic changes in the abundance of lobsters, a concept which is not supported by biological and economic information developed since 1939."

Since 2012, the Gulf of Maine lobster settlement surveys have declined, pointing toward eventual declines in the lobster spawning stock.  The decline has been so pronounced as to concern lobster fishery regulators.  On February 1, 2023, The Atlantic States Marine Fisheries Commission American Lobster Management Board released a draft addendum No. 27 – a proposal to consider measures to increase protection of spawning stock biomass of the Gulf of Maine/Georges Bank lobster stock.  Information about proposed lobster regulations can be obtained from Caitlin Starks, Senior Fishery Management Plan Coordinator – email [email protected].

[king crab 48]

Once again, Great read !  Congrats on retirement, Health is most important now!  Hope someday to meet up with you ,  share a little knowledge.  I believe this year is going to be banner!! ,  I for-see many 8 inchers to be reported .