Monday, July 16, 2012

Connecticut blue crab report #5 - Small crabs and sponge crabs appear

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 #5 – July 9th, 2012
You Do Not Need To Be A Scientist To Report!

·         Small crabs reported in several areas – Bridgeport/Fairfield areas report heavy concentration of sponge crabs;
·         Hand liners frustrated by strong tides; nighttime netters do well;
·         Small crabs entering the Connecticut River at night using the strong flood tides;
·         Temperatures show slight increase as reports from USGS shows Connecticut River tidal wedge forming;
·         Conch populations now reported off Guilford, several small 2 inch crab sightings. 

In one of the best signs that large numbers of 3 to 4 inch and some 2 inch crabs survived Irene came from several recent observations about them; thank you for these reports! They are very helpful. 
Small 2 inch crabs have been reported in Wequetequock Cove, Stonington, north of Masons Island in the Mystic River, South Cove, Old Saybrook, Guilford/Madison shore; West Haven shore; the westerly side of the Housatonic River and in the Darien River.  Small 2 inch crabs were seen in the Oyster River, Hammonasset River and Branford River many observed with the incoming tides.  Dense concentrations of female ova carrying sponge crabs have now been reported for the east and west- the mouth of Pawcatuck River; Little Narragansett Bay; Mystic River below the Seaport; West Haven shore; the Bridgeport/Fairfield area (also the hot spot from last year).  All reports mention increases in the 3 to 4 inch size in crabs.  This predicts a good season. 

What has been “quiet” is information about Housatonic River.  Last year it had masses of 3 to 4 inch crabs at the southern marshes (mouth) and western side, but no reports of similar masses or adult crab movement?  One explanation could include that Irene delivered an immense amount of silt (and nitrogen also) from our long tidal rivers, the pictures of the silt entering the sound at the mouth of the Connecticut River is dramatic.  (See UCONN Sea Grant’s Wrack Lines issue Vol. II #2, Fall/Winter, 2011-2012 an incredible article. The article is titled: Tropical Storm Irene Delivered a Sunday Punch to Connecticut” by Marybeth Hart.  The article is outstanding and describes the tremendous storm changes/damage along Connecticut’s coast, (pg 3 to 6.)

Strong fresh water flows pushed the salinity very low in many rivers.  A similar occurrence may have occurred in the Housatonic River.  However despite the large Connecticut River fresh water runoff crabs survived in North Cove, Old Saybrook, the site of a dredged harbor of refuge (a refuge also, it seems for blue crabs) and the first reports of Connecticut River blue crabs can be seen here the past three years.

It is the frequent reports of large numbers of sponge crabs that may lead to a good “native” Connecticut Megalops set later this summer.  The amount of female ova carrying crabs is unprecedented according to some crabbers.  The numbers are certainly higher that than the 2010 and 2011 years sponge crab and small crab reports are very helpful and I thank those crabbers that sent in reports after report #4.

·         Up until the strong moon tides shore hand liners were doing good, but night time netters have pulled way ahead, with large catches.  Most of the hand liners have had difficulty with the recent strong moon tides, either keeping the bait on the bottom or after hookups having the crab ripped off the bait.  One clever blue crabber in Clinton used the strong tides to advantage casting a chicken leg up current with a small sinker and reeling the crab on the surface past a friend who then netted them (no second chance) with four fishing poles rigged this way a dozen large crabs came quickly as hand lines and potters caught little.
Look to see catches from shore improve as currents lessen.  Nighttime netters report good to excellent catches, but as yet very few soft shells.

·         Small crabs entering the Connecticut River at night.
July 6th had thousands of 2 inch crabs hitching a ride upstream on the moon tides past Essex Town Dock.  I observed hundreds of small crabs on the surface swimming past the dock.  In a flashlight beam they were hard to miss- the striped bass had noticed them also as frequent splashes signaled an evening feeding opportunity.  The tides have been very strong but the amount of small 2 inch crabs on the surface now was a surprise.  This size had been scarce until the Fourth of July but now seem to be present in many areas along the coast.  This is the late 2011 Megalops set (not the overwinter Megalops set) that grew before winter.  The 3 to 4 inch crabs are 30 days from legal size, weather depending and should be 5 inches by August 1st.
Will the adult population hold out until then, that’s not certain yet, although that did occur in 2010; we had the 2 inch and 4 inch crabs both mature into legal sizes during the summer with the large population of legal size adults the equivalent of 3 sets reaching legal sized all at once—and it was an incredible blue crab year (2010).

The reports of central Connecticut although positive, the western sections remain (except for a few isolated reports) quiet, just the opposite in 2011.  Perhaps the next few days will have some crab reports in the west.
Sometimes, according to some crabbers fishing drops because of shedding and then suddenly takes off again. 


Weather temperatures show slight increases-
Connecticut River wedge strengthens
Sea water surface temperatures continued to inch up and July 6th reports as follows from Long Island Sound current sea water temperatures from the NOAA National Data Buoy Center (Http://www.ndbc.noaa.gov/).
New Haven Harbor 71.4°F
Black Rock Harbor 69.3°F
Execution Rocks – (New York) 73.9°F
And areas south at Sandy Hook, New Jersey 81.9°F
And Montauk to the north a cooler 70.9°F

The salt water wedge strengthened considerably from July 2nd (thanks to a helpful United States Geological Service (website http://waterdata.usgs.gov/ct/nwis/40 Report #8) - that maintains a tidal sensor on the Connecticut River in Essex.  Here the site displays several functions but you can graphically watch the salt wedge strengthen in the Connecticut River; US Dept of Interior US Geological Survey titled USGS current conditions URL http://waterdata.usgs.gov/ct/nwis/current  
(If you have a chance check out this site it is very interesting.)  A nighttime Essex observation found hundreds of small crabs using the strong moon tides to move up river.
·         Small crabs a good sign/conch reported off Guilford, West Haven and New Haven.  The reports of 2 inch crabs earlier this spring in the east and now a few shore reports from Guilford to Fairfield are good signs.  These crabs depending upon the summer’s growth season with reach legal size before fall.  The smaller size less than an inch has yet to appear.

But add to that observations of small conch reported in Clinton Harbor, Guilford shore, Branford shore and Milford – some in areas and quantities seen never before only speaks to species changes/shifts in Long Island Sound.  Years ago, conch harvests in Connecticut were relatively small and generally not in commercial quantities.  That started to change in the 1960s.  As Long Island Sound warmed conch populations increase again subject to storm filled cold winters.  By the late 1970s conch became prevalent (channel whelk) especially in central Connecticut from Old Lyme to Milford.  They seem to populate the sand bars shoals along the 10 to 30 feet contours-smooth bottoms seem to be the best habitats.  But dense populations were reported last year in the Bridgeport area and this year between Branford and Clinton. 

The popularity of conch seafood dishes recipes has also increased once termed the forgotten shellfish and a coastal Native American favorite its popularity has jumped region wide in the last five years.  To learn more about conch, see the
 The History of Madison’s Finfish and Shellfish Industries.  It is report number
#47 on the Sound School directory http://www.soundschool.com/directory.html  The paper includes a description of Native American fisheries and some conch recipes.  For a more recent report on the Conch Fisheries of Connecticut contact Susan Weber at susan.weber@new-haven.k12.ct.us and ask for report titled, The Rise of the Abundance of Conch in Long Island Sound with Warmer Temperatures, December 2011.

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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