Friday, July 27, 2012

2012 Connecticut blue crab report #6

Here's Blue Crab Report #6 for The Search for Megalops:

The Connecticut Blue Crab Populations and Habitat Study 2010-2015
The Sound School - The ISSP and Capstone Project Proposal
Building a Network of Citizen Monitors
The Search for Megalops
Report #6 – July 19th, 2012
You Do Not Need To Be A Scientist To Report!

·         Connecticut DEEP confirms pesticide residues found in lobster tissue (organs) – blue crab concerns – my view;
·         Megalops set survival confirmed by many reports –small crabs abound in central Connecticut – Connecticut River crabbers doing well;
·         What’s happening to Connecticut’s blue crab populations?
·         Catches increase for central shore hand liners and trappers; where to crab;
·         Western CT, still has few crab reports; discouraging news from the Norwalk River;
·         Thanks for your reports!


This report was delayed for several days after the Connecticut Department of Energy and Environmental Protection (DEEP) announced the results of September 2011 testing that found residues (trace amounts) of Methoprene and Resmethrin in lobster organs.  Questions and dock discussions immediately turned to blue crabs health and potential impacts (if any) to Connecticut blue crab populations, especially the Megalops life cycle for blue crabs.

Blue crabs by their very biology and life cycle habitat requirements live next to and in salt marshes, the same areas that were reported to be treated with pesticides to reduce the West Nile virus threat (mosquito vector control).  At this time it appears that Connecticut switched treatment procedures in 2011, but additional testing is reportedly underway for lobsters.  No direct concern about blue crabs has been made in media articles.

The impact of insecticides upon lobster populations as claimed by lobster fishers for decades here needs a review, especially in high temperature, low salinity, low pH areas.  In 2010, I reported two instances of pesticide suspected impacts to blue crab populations- one in 1971 and one in 1982.  The report titled “Where Do All The Blue Crabs Come From?” dated December 2010 was made available in January 2011 and it is program report #2 for the Search for Megalops.

Without extending this discussion and delaying the report further, we’ve posted Report #2  for any blue crabbers interested in this topic on the web sites CT Fish Talk, The Blue Crab Forum and the Blue Crab blog run by Dr. Matthew Ogburn. 

Dr. Eric Schott of the University of Maryland Center for Environmental Science who also reached out to crabbers here on blue crab health issues before has also obtained this information.  (See reports #3 and#5 this year).

As a member of two Long Island Sound Study committees, to the CT lobster fishers who continue to report their concerns, my appreciation, confirming “You don’t need to be a scientist to report.”  We do need to know much about our shallow water habitats for many species.
Tim Visel

Small Crabs in Central Connecticut – Waves of small crabs reported.

After July 8, I obtained several reports of the first ¾ inch to 1 inch size blue crabs and its large numbers – perhaps in the millions.  On July 11th, what could be described as waves of small crabs were observed along the central coast.  Starting in Milford/West Haven on July 8th ending with small crabs in Guilford on the 10th and further reports from Milford and West Haven reporting huge numbers of small crabs on the 11th and 12th.  This is the first news about the Megalops over wintering set; it did survive both the stormy summer and October blizzard and should be the 3 to 4 inch crabs by September (next years legal crabs). 

The two inch and 3 to 4 inch size crabs also inched up along with the legal catches.  Look for crabbing to increase for central Connecticut it’s looking like a better crab season than 2011, still too early to tell about the east but historically the past few years crabs mature later about a month after, from cooler water, so what has been good crabbing in Clinton on July 15 has been August 15 for the eastern state – Pawcatuck River fishery.  The western areas continue to have few reports of legal size crabs, but one observer made an excellent comment:  the inch to ¾ inch crabs might still be present; they just don’t show up in the crab nets, the mesh size is too big and the small crabs just fall out.  That comment was followed by another:  that seine net surveys might be a better way to determine Megalops and small crab survival at least the first few weeks of the summer and I agree.  Use of a seine net is a better way and one used in the southern crab producing areas, good suggestions!

While catches continue to increase for hand liners and pots (traps) the central sections show improved numbers of small crabs running 2 to 1 to 3 to 1.  Crabbing in these areas will improve.

The great news is that the ¾ to 1 inch size is starting to show up and in large numbers!  Still waiting for any news about crabs in the west, particularly between the Housatonic and Norwalk Rivers, excellent blue crab areas in 2010 and 2011.  Two recent reports from the Norwalk area report few or no blue crabs as yet.

What’s happening to Connecticut’s blue crab populations – more about lobster and blue crab habitats

While watching quite an active Baldwin Bridge DEEP fishing pier (Old Saybrook side) over the weekend, and discussing recent catches one crabber came over and asked me, “What’s going on with Long Island Sound?”  He had caught 17 large blue crabs in an hour (not a complaint) while years ago that was a day’s catch.  I agreed and the recent newspaper accounts of declining lobster populations were a concern.  How could the crabbing be so good and the lobster populations be in such tough shape?

Several crabbers have asked about the abundance of blue crabs and lobster declines recently.  Part of the explanation of why crabbing in CT has been good for the last two decades and lobstering has not, is habitat quality.  I think it is important to include two key factors which are frequently overlooked in terms of historical habitat patterns, and fisheries abundance combining energy levels and temperature.

At the turn of the century it became very hot in New England (The Great Heat 1880-1920) and at this time blue crab abundance soared while Connecticut’s lobster population crashed.  We have good historical resources from the Biennial Reports of the CT State Board of Fisheries and Game that describe regional efforts to build lobster hatcheries at the turn of the century to replace post “Megalops” stage 4 lobsters.  All the New England states built lobster hatcheries between 1899 to 1910; all of them even Maine (New York also later).  In fact, the Maine facility in Boothbay Harbor Maine was the largest ever constructed in the US releasing hundreds of millions of stage 4 lobsters and “fry” into the environment and coastal waters.  Connecticut fishermen felt the lobster hatchery effort had helped and testimony from individual fishers and fishing families has survived in the historical literature, abstracted from the 1911-1912 ninth biennial report.  Since the lobster population crash, (1898 to 1905), by 1910 fishermen noticed increases in small lobsters and made comments about the increase of small lobsters in 1912. 

Report of the CT Lobster Hatchery (Started in 1905) for the Period of 1911-1912 – comments from fishermen (Guilford) pg 14, see footnote.
* Guilford – “As my figures show I have caught very few large lobsters and very few egg lobsters this year, but there is no question in my mind as to the increase of small lobsters, and that is due to the hatchery work.  Whether these will be permitted to remain in the water long enough to grow to legal size, is another question which I cannot answer, but I fear not all of them will.” (1912 comment)

* Guilford – “The marked increase of small lobsters is very gratifying, and is sufficient proof that the hatchery is one of the greatest institutions in the state, and I shall do all I can to help the Commissioners of Fisheries and Game in the protection and propagation.” (1912 comment)

* Guilford – “I never saw so many small lobsters in my life as there is this season.  Why don’t you try to pass a law so lobstermen have to space the slats further apart?” (1912 comment)

And page 16 is the following report (1912- lobster hatchery)

Noank Station in procuring the eggs for the operation of this station the same general policy has been pursued as heretofore, by purchasing the adult lobster with the egg attached.  These were collected from the fishermen the entire length of the coast, who are paid the full market price.  After the eggs have been removed and placed in the hatching section from which they originally were taken.  The fry hatched from the eggs are plated in the waters of Long island Sound, as near the same locality as possible from which they were taken.

During the biennial period 1,474 ripe egg lobsters have been collected, from which 25,585,990 eggs were obtained, resulting in the hatching of 22,750,000 fry which were planted in the coast waters.

During this same period there were also collected 1,586 green egg lobsters, making a total of 3,060 egg bearing lobsters collected, of which number 1,586 were held in cars during the winters, and the balance, 536, were returned to the water.

In the seven years of the operation of this hatchery, 208,761,870 fry have been hatched and liberated.”

Although Connecticut’s lobster hatchery effort was commendable it paled in comparison to the Maine Lobster Hatchery at Boothbay Harbor, in seven years 1905 to 1912, Connecticut procured and spawned out 4,500 eggers for about 209 million lobster (fry).  The Maine facility was spawning out almost 3 times as many eggers (14,000 each year) for hundreds of millions of Stage 4 lobster and fry each year.  Eventually most of the hatcheries released Stage 4 to help increase survival.

[State of CT Public Document No 19- Ninth Biennial Report of the State Commissioners of Fisheries and Game for the years 1911-1912 to His Excellency the Governor and the General Assembly, Hartford, published by the State 1912].

I think what we are experiencing today is a massive heat/energy habitat reversal.  As temperatures warmed, the habitat quality improved for blue crabs (I estimated that in 2010 Connecticut contained between 80 to 120 million blue crabs) and declined for lobsters.  This habitat reversal (failure) resembles the period between 1898-1905 – lobsters crashed and blue crab populations increased.  Key to this is the blue crab Megalops if it also finds Connecticut’s habitats more favorable and the reports this June and July of huge numbers of female sponge crabs also needs to be taken into consideration.  Is this new habitat/fishery territory- no not from examining the historical fisheries / literature, we have experienced this before.  When it got colder in the 1950s and 1960s, lobsters increased and blue crabs declined.

Catches Increase for Central Connecticut shore hand liners and trappers

What started off as a regular reporting period grew more complicated after July 10th.   Crabbing was generally good, shoreline potters and hand liners were observed with catches between 20 to 30 adults.  A Clinton Harbor catch (July 12) saw over 40 adults between 6 and 7.5 inches (I measured some with permission).  Catches at the DEEP Bridge also was good; this is the DEEP Old Saybrook Boat Launch facility.  This includes a large public pier which is excellent for families wanting to crab, but on weekends (July 14-15); I found the pier packed – a count of 42 crab traps alone.  Early mornings were the best; some crabbers were leaving around 7 a.m. reporting the best catches between 1 to 4 a.m. in the morning.

All the reports indicated the incoming tides are the best – slack tides “awful” and keeping baited traps on the bottom less problematic.  It’s about this temperature last year-- the deeper area channels and river bottoms became better for crabbers.  It was felt the warmer temperatures were not the best for crabbing on the shallows and after July 30 last year shore crabbers did better at night than those during the day.

Look for deeper water for the best catches in a few days; crabs move if it becomes too hot.  For example, the Lieutenant and Black Hall River crabbing occurs mostly from boat fishing just north or south of the bends. A local river trapper would set crab pots on the edges at the depth he would “strike (find) them” and at the bends tidal action tended to create these “holes”; (he declined to provide the location of his favorite deep sets).  Some of the best crabbing areas recently have been in dredge cuts made in tidal rivers, the one just north of Route 1 Bridge, Clinton side, on the Hammonasset River and just north of Route 1 Bridge Old Saybrook, Route 1 Bridge Oyster River.  The tidal dredge cut at Westbrook north of Route 1 has legally been posted, no crabbing.  This occurred during the 2010 crab season which saw crabbers seeking out “pole crabs” – those who were found clinging to pilings and dock floats and the increased use resulted in the postings (closures). Access to the water and crabbing spots has been the subject of many questions:  I would like to go crabbing where should I go?  One of the things that I have learned is that crabbing is hard to predict, it may be good one day and dismal the next.  The other question is access and CT DEEP has funded and built some excellent crab and fishing docks, an overall state shore guide is found at: http://www.lisrc.uconn.edu/coastalaccess/ 

Certainly a good family starting blue crabbing place could be the DEEP Marine Fisheries Dock/Pier Old Lyme, adjacent to the DEEP Marine Fisheries facility and the DEEP fishing pier at the Baldwin Bridge boat launch – Old Saybrook side slightly upriver.  Both sites are excellent for beginning crabbers and critical to providing public access to Long Island Sound.

As catches increase in Central Connecticut look for deeper access for best catches.

Western Connecticut Discouraging News – Almost no adult blue crabs!

Western CT crab reports are few and limited to sightings not catches in Western CT. Observers continue to report few if any crabs.  Aside from a few sightings in the Norwalk River the west has few blue crabs.  One observer who has been checking the Norwalk River (thank you again for all the reports) weekly has seen no crabs and no crabbers.  This is in stark contrast to the 2010-2011 seasons.   But as the summer progresses crabbing yet may improve, but it is discouraging to some crabbers nevertheless.  Key to the west aside from some salt ponds is the Housatonic River which had large sublegal populations in the salt marshes last year.  The first reports of large numbers of small crabs came this year from the east not the west which is also in opposition to the 2010-2011 seasons.  In 2011 the Housatonic River mouth was suspected in providing millions of small blue crabs that moved east and west with the tides and Bridgeport was one of the first early report locations last year, this year no adult crab catcher observation reports.  Female sponge crabs were reported earlier but soon left, perhaps for deeper water?

Any western crab reports would be greatly appreciated even if you went out and did not catch anything.  Just reporting the crabbing effort is a help.  News/observations of small blue crabs in the west, especially west of the Housatonic River would be especially important.


All Blue crabs and Megalops observations are valuable; please email them to me at tim.visel@new-haven.k12.ct.us.

Program reports are available upon request, 1-4 catch/observation reports 1-15 are also available from last year.
For more information about New Haven Environmental Monitoring Initiative or for past reports please contact Susan Weber, Sound School Adult Education and Outreach Program Coordinator – email to: susan.weber@new-haven.k12.ct.us
If you would like to receive these Blue Crab reports, ask to be placed on the email directory.

If you do not wish to receive these reports, please let us know.
Looking forward to hearing about any Blue crab research.

Tim Visel

The Search for Megalops is part of a Project Shellfish/Finfish Student/Citizen Monitoring Effort Supported by a 2005 grant to The Sound School from the National Fish and Wildlife Foundation grant #2005-0191-001.
Watch for the Megalops Portal on The Sound School website http://www.soundschool.com/
The Sound School is a Regional Agriculture Science and Technology Center that enrolls high school students from 23 cooperating towns.

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