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BlueChip
Joined: 29 Jun 2011 Posts: 177 Location: New Haven/Madison/Essex
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Posted: Wed Oct 16, 2013 1:54 pm Post subject: Fall Crabbing in Central Connecticut -Report #11- 10-14-13 |
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The Sound School – the ISSP and Capstone Project Proposal
Building a Network of Citizen Monitors
The Search for Megalops
The Connecticut Blue Crab Population Habitat Study 2010-2015
You Do Not Need To Be A Scientist To Report!
The Search for Megalops –Report #11 -2013 – Blue Crab Year
October 14, 2013
• Fall Crabbing In Central Connecticut
• Watching For Megalops – Seine Studies
• Crab Studies For School Groups
• Cole B. London – Barnegat Bay, Part II, Post Super Storm Sandy
• Blue Crab Killie Ring Baits – Summer Conversations
• Western Crab Reports Offer Promise
Fall Crabbing In Central Connecticut
We have had a good fall season in central Connecticut and catches until October 12th at Essex have been very good. Crabs are still hungry and high tide catches have been a 5-10 crabs/hours now dropping to 5 crabs/hour. I had planned to go blue crabbing with a Sound School teacher and we hit the Essex town dock at 1:30pm. What I didn’t know was happening on the dock that day was a regional water safety swim test for dogs, and despite a hundred dogs --some swimming-- and boaters trying to get good pictures, we ended up with 15 crabs, thanks to generosity of a fellow crabber and one white perch fisher. Essex Town Dock temperature is now 62 degrees and falling. On October 13th the crabbing was good for about an hour before high tide at Essex but the while perch fishers who cast into the channel were catching at times a white perch and a blue crab together. The white perch fishing was fantastic (grass shrimp bait).
Blue crabs have been observed at Seldens Creek State Park recently and they still may be moving down river. The deep channels have crabs and with 48° the temperatures at which blue crabs stop feeding, there is still plenty of time to catch a nice meal of crabs.
Kirk, my crabbing colleague, did not miss one crab, 10 in a row but the number of “hook ups” was huge – there were a lot of crabs but upon leaving the bottom they just let go. They just might be sensing the cooler surface water but it did make me think about breaking out my rusty box traps and retiring my Vexar™ net bags for the season.
Look for crabs now in these dredged deeper marina channels – crabs will continue to feed but it seems they find these areas and stay. Look for a different type of habitat compression – crabs sought out the deep channels this August to escape, very hot temperatures now the deep channels offer some “earth warmth” instead.
Enjoying the fall weather,
Tim
Watching For Megalops Sets
In 1941, Dr. E.P. Churchill of the Chesapeake Biological laboratory published the first comprehensive report on the reproductive stages of the blue crab and it remains one of the key studies about them. A year later (1942) an experiment was undertaken to have a “spawner population” transplanted into areas now barren of blue crabs. After 1925, huge declines in blue crab production occurred in the Chesapeake Bay (thought now to reflect cooler water temps), with a catastrophic decline in 1941 three years after the 1938 Hurricane. Graham and Bearen (1942). The study sought to replenish crab reproductive success by transplanting egg bearing sponge crabs and concluded that Megalops the “bottom dwelling forms” are difficult “to collect in the field.” Dr. Churchill is also credited with the term of a Megalops set as they too seek bottom habitats to burrow. And, like other setting organisms, water temperature could determine timing. Reaching the 1 to 2 inch size seems to be very important before winter, and this aspect looked at during the 1940s and 1950s, “young crabs hatched in late summer may grow slowly during the cool fall months.” A cool spring may delay the Megalops until it was too late to feed and grow. The blue crab seems to have a built in self-defense against this habitat failure, it can suspend the post Megalops stage for over 100 days, avoiding the coldest of temperatures. Few marine organisms can do this, thus one cold winter would not be catastrophic but three in a row could be. A cooler pattern would impact blue crab habitat quality as it did in the colder 1950s. Blue crabs and oysters do see to share similar habitat profiles. Estuarine shell might be the place to look for the Megalops sets, followed by eelgrass in oxygen sufficient areas; each Megalops set would define the “year class” from it.
The oyster industry under some of the first biologists – Belding, Prytherch, and Loosanoff put out test bags of oyster shells and monitored them closely for the beginning “wave of oyster setting”, institutionalized by John Volk Aquaculture Biologist for the New Haven Long Island Oyster Farms Company in 1979.
Many times the Connecticut oyster industry maintained adult spawning beds, planted shell transplanted spawners only to see no set; the waters were too cold, fresh, or stormy. They had a cold water habitat failure, and looked to oyster hatcheries in 1970s for the survival of the industry. So it is not surprising that some of the first scientists to focus upon the importance of recruitment and habitat quality was from the shellfish industry such as NOAA’s, Clyde MacKenzie, which soon spread into other fishery divisions as well after 1968.
The “year class” concept was greatly expanded in the striped bass rebuilding effort of the 1970s and 1980s as attention turned not only to a spawning capacity (again important) but also the health and “index” of habitat quality for shallow nursery habitats – you do need both. Here inshore seine surveys of known “young of the year” habitats produced data that predicted “year class” success. By examining the abundance of juvenile fish you also examine the health of habitats that sustains them. And people now informed about their importance went out to check “ground truth” on those habitats which are today termed essential.”
The Search for Megalops hopes to do the same for small blue crab post Megalops, the star stage, that very important nickel to quarter size “recruit,” the 1 to 2 inch size. School groups and civic organizations could provide some key research information on the smallest sizes of blue crabs, with just the common minnow seine nets as we have so many creeks, coves, bays and salt ponds. A seine survey could help identify the habitats in which give blue crabs a chance, and live apart for the first few important weeks away from predators, even larger blue crabs themselves. We know that competition between your classes is significant (cannibalism) and from the reports of the first few years break into four general sizes; Megalops to 1 inch; one 1 inch to 2 inches, 3 to 4 inches and 5 inches and up. Some of the best blue crab years 2008, 2010, 2011 (east) have been preceded by reports of springtime reports of large numbers of 1 to 2 inch size blue crabs. We still know very little about the Megalops set itself, the post larval stage that lives in shallow areas (Report #1, January 2012).
Seine surveys could help fill in many blank areas when it comes to habitat functions for the blue crab. Always interested in any blue crab observations for questions and for more information on seine surveys, please contact tim.visel@new-haven.k12.ct.us
Crab Studies For School Groups
One of the long considered basic rules for fishing scientists have been “show me a large reproductive capacity” but a newer look for healthy fisheries and habitat condition evaluation has changed – “show me a successful year class”. A year class is a set or reproductive event, a scallop set or oyster set and for this study a Megalops set. It is basically a focus not so much on the reproductive capacity of adults which is important but the second view that looks at habitat quality for the young. It is a division that enters into the overfishing debate have we overfished species to a point that reproductive capacity has ceased (The Atlantic Halibut, for example) or did the die-off of lobsters in 1898 here cause overfishing of them a century ago? Most likely not, lobster fishers weighed in with observations then that all of the small lobsters (far below legal size) had also perished- the truth of the matter is we had a high heat habitat failure for the young. Simply put, years that entire classes of lobsters died before “recruiting” into the fishery. The young had suffered a habitat failure. The fishing potential of the industry quickly reduced any legal size lobsters, giving the appearance of “overfishing” in 1905 but any lobster that could, bottom walked out of Long island Sound; those that could not, perished in the high heat. The Noank lobster fishers of 1905 were not responsible for The Great Heat, they weren’t responsible for the die-off of lobsters either. The climate here turned against the lobsters and lobster fishers as well.
Just how hot it was in the 1900s here we can look to USDA reports; each year had a report of the climatologist and chief of the Division Weather Bureau. Farmers as fishers looked to habitat conditions for economic success, thus great attention was paid to agricultural climate and habitat conditions; the 1912 report gives us an idea of the severity of the “heat” back then.
REVIEW OF WEATHER CONDITIONS DURING THE YEAR 1911.
By P.C. Day, Climatologist and Chief of Division, Weather Bureau.
The following summary of the weather for 1911 conforms largely with that appearing in the several numbers of the national Weather Bulletin, issued by months during the principal crop-growing period, April to September, inclusive.
The feature of the year’s weather that stands out most prominently in its effects upon the wellbeing of the people during the year and that will doubtless serve as a standard of comparison for many years to come, was the long and excessively heated period that prevailed over most of the districts east of the Rocky Mountains from the early part of May to the early part of July. During this period of slightly more than two months a series of hot waves of marked severity, for so early in the season, followed one another in such rapid succession as to produce an almost continuous period of heat not surpassed for intensity or duration in many years.
The effects of this continued heat were most pronounced over the more northern portions of the country, where in the congested parts of the great centers of population the suffering was intense, and thousands of deaths resulted from the direct effect of the severe heat.
Yearbook of the United States Department of Agriculture, 1911, Washington DC, GPO 1912, 742 pages.
And during The Great Heat in southern New England, blue crab populations soared – what was good for the adults must have favored recruitment (the young) or each “year class” as well.
The oyster industry a century ago pioneered the importance of determining early “year class” recruitment as clean oyster shell only had a 20 day window of catching a “set”- a young oyster veligers gluing onto it in search of “home”. Putting your shells out too early would be an economic disaster as by the time oyster spat (an old industry term from England) looked for shell, it was covered by natural encrusting algae, which was “slippery” slimy and oysters couldn’t glue on. Putting your oyster shells out too late was just as bad, here clean oyster shell found that oyster larvae had “set” too soon and landing in acidic Sapropel perished instantly, results were the same for both, a low number of seed oysters and poor harvests years in the future. The industry has known that for a century success or failure was tied to the “set”, not the number of eggs produced. The oyster industry in the 1950s faced a declining habitat quality for oyster sets, not by a lack of spawn, but cooler winters that caused the set to occur too late.
The same might be true for blue crab Megalops sets- looking at weather and historical crab and lobster catches could be something that school groups could take on as a “class” project. The University of California is now putting the Connecticut Dept. of Fisheries and Game Biennial Reports online. These two year reports have many sections developed to the die off of lobsters at the turn of the century and fisheries landings.
The Dept of Agriculture also has completed the report of the climatologists from the years back – it is possible to look at long term weather and catches. If a school group is interested in this climate period, 1880-1920, National Public Radio has a great segment titled, The Great Heat Wave of 1896 and the rise of Theodore Roosevelt. If you are looking for study material for historical climate events, this segment is a must see.
Cole B. London – Barnegat Bay, Part II, Post Super Storm Sandy
Last spring (May 15, 2013 Report #2) Cole London reported on his blue crab research over the summer in Barnegat Bay, New Jersey. That report went on to become the most viewed report on New England Region Blue Crab info division as New Jersey crabbers joined into our study. Cole’s second report is valuable not only as a blue crab population report but for the observations of habitat change post Sandy something that is a frequent topic here in New England. Many of Cole’s crabbing locations were destroyed by Hurricane Sandy. Remember that each state has its own rules and regulations for blue crabbing. Thanks Cole, for the report-
Tim Visel
Cole B. London, Sound School student (2013)
This summer 2013, in Seaside Park, Barnegat Bay, NJ, I have done another Megalops study on the blue crab population. I did a follow up from last year but this time I was also doing records to see if Hurricane Sandy had any effect on the crab production. I have noticed many different changes, not only in the size of the crabs but the type of crabs; I have noticed there were a lot more female crabs and they were much smaller. Also, in 2012 there was a lot of eelgrass; this year I’m assuming since the hurricane came, it took out most of the eelgrass. This year I have noticed where the eelgrass was, there is now a lot of sand, rocks, shells and dried up seaweed. Also there was a lot of broken glass and garbage. If the hurricane didn’t affect the grass then it either just got killed by fish or maybe some researchers took it out. In one area there were some construction workers changing sewer line and underwater works. I believe there is more research that I should look into.
Blue Crabs in the Barnegat Bay Post Super Storm Sandy, by Cole B. London
I completed a search for Megalops blue crab study based upon crab catch observations during the summer of 2012. This summer of 2013, I am crabbing the bay to determine what changes are observed in the catch post super storm sandy (PSSS). I decided to do this study again because I wanted to study the effect hurricane sandy had on their population
The Town of Seaside Park faired pretty well in comparison to other Towns, like Ortley Beach just to the north. Ortley Beach had major destruction from the storm surge of the Atlantic Ocean on one side and the Barnegat Bay on the other side.
Over the years, Seaside Park has fostered the creation of dunes on the Atlantic Ocean beach side upon which dune grass and sand rose had been planted to prevent drifting, erosion and protection from storm surge. There are no houses adjacent to the ocean beach in Seaside Park. On the bay side of town the surge protection is limited to a wooden barrier between the road, the beach and the water. The beach varies in width from zero to 20 feet +/- . There are no houses adjacent to the bay beach, but the described protection is very limited. My family’s house is on the bay side and the surge went thru the lower level leaving a 5 inch thick coating of bay mud. Our 20 foot runabout, which was in the driveway wrapped for winter, was found blocks away and the trailer was found in another location both were totaled by the insurance adjuster. All my crab cages, drop lines and nets were lost as the surge pushed our storage shed off its foundation, and was found on its side with no door or windows and the contents lost.
My PSSS blue claw crabbing is different than my previous Megalops Study because there is no boat or pier to crab from and all my crabbing equipment was replaced. In addition, I am working six days a week on the Beach Crew for the Seaside Park Public Works Department. What remains the same is the field observation chart for recording the blue claw crab catch data.
As my time is more limited this year due to my Beach Crew work, I am using a 24” long by 12” wide by 12” high trap, which is attached to a buoy and placed in the water for 3-14 hours. The location of the trap varies depending on how far I can walk out in the tide. I have been using bunker as bait. The bay floor is sand and rock, which is unlike last year where it was mostly mud and grass.
I started this study this summer on 7/28/2013 and ended 8/23/2013. Last year I had 22 females and 36 males this year there was 28 females 39 males . The number is almost the same as last year showing the difference is not that great.
This year I walked into the bay about twenty - thirty feet out and dropped a cage with a full bunker fish each time. I would leave it out for a three hour minimum or a max of 14 hours depending on what I was doing. The water temperature was between 70 - 74 degrees which was much cooler than last year which had a high of 78. It was a rocky/sandy habitat usually about 3 to 5 feet deep. The weather was mostly sunny days and clear nights. It was often windy and I retrieved the trap in a hard rain with a windblown chop once.
I observed that the catch was greater when the trap was left over night than in the day time. I have 18 trips recorded and some trip were forgotten to be recorded. Most crabs caught were greater than 3 and up to 4.5 inches. The males seemed to be plentiful and larger while there were less females which were much smaller and not so lively.
Last summer I caught an abundant number of crabs of less than 3 inches. This was done from a pier with a net. Using the large crab trap this year, I think they might have escaped over the time the trap was left out in the bay, if any were trapped at all. The larger crabs could not escape. It also could be that the PSSS rocky/sandy bay bottom provided less food and vegetation or places for them to hide, breed and live With this change the small crabs could be eaten by predators and that was why the small crabs were not caught.
In conclusion my PSS search for Megalops did not show a significant difference in the overall number of crabs caught in the 4 inch range. What it showed is that the bay environment changed from grass/mud to sand/rock and that small crabs were not caught.
Blue Crab Killie Ring Baits – The First Blue Crab Sport Fishery?
I had a couple of conversations this summer with crabbers who still use metal ring baits; this is an older form of hand line crabbing that some people still use but dates back to the 1940s and 1950s (and perhaps before that). Here a metal ring is used to hold small “mummy chubs” strung onto usually a heavy gauge copper wire . The crabbers I saw this year used something different-- bait on a floral wire, a short section of metal wire (green) wrapped around a lead sinker and the free end (wire end) passed into in the bait and once the bait is strung, the metal loop is finished to the same lead sinker. I saw strung squid (never used by me), heads of menhaden and the Atlantic silversides shiner (Menidia menidia) used this way over the summer.
When I worked on Cape Cod in the early 1980s I watched blue crabbers also string “mummies” on a copper wire loop, fairly stiff and attached with a heavy duty snap swivel to a sinker, then to heavy manila twine. A wooden board with three grooves cut into it was pushed into the marsh which held the three lines up off the marsh and in full view. A loop was placed into the grove and when one line twitched, the loop dropped and signaled a hit. The crab was slowly drawn in. More times than not the crab was hanging on to the metal ring and not the bait. (You had to be attendant.) Instead of the wood holder, many held the lines so you could feel the hit, they swore by this method and claimed the ring of mummies (Fundulus species) was almost irresistible to blue crabs, perhaps so, but I envisioned a large crab stripping the bait from quickly from the ring, I always used a fish head and twine (line) again tarred manila that was part of a rectangular frame spool called a crab line. I see these at coastal angler shops frequently and it brings back early great memories of blue crabbing. This year I was surprised to see this wire ring method again after so many years, because in many of the rivers I fish, sticks and branches are constant potential snags, something like this could get caught and break the ring I suppose, releasing the bait, but the crabbers I spoke with said it was “the best.” Clean up was quick also the ring released and bait quickly stripped from the wire ready for the next crab day. I do agree on one thing, if you use shiners or killifish, perhaps the only way to use them is on a wire.
I had seen this method before many years earlier growing up in Madison with a neighbor who still blue crabbed in Tom’s Creek; she used the ring and captured killifish (Fundulus species) with a circular metal trap hung in a salt marsh tidal ditch. Once sufficient supply of “mummies” was caught they were placed on the ring, attached to crab lines. She swore by this method and I must say at the end of the day her basket may not have contained the most crabs, but certainly the largest. She also stood back from the creek edge, out of sight but held the lines, (and not the cut grooved board seen on the Cape); it was more like a fishing experience of actually “feeling the bite”. The creek at that time was full of oysters and low tides, lots of mummies. It was very effective but perhaps time consuming to string the bait and recall that a large supply of killifish was needed. We always had access to fish heads which was for us quite okay.
I mentioned this to Phil Schwind (when I worked for the University of Massachusetts); he had written a few books on Cape Cod fishing and he told me he thought this dated back to the turn of the century when “sport crabbing” first started on the Cape, when some of the first crab lines were just baited hooks on hand lines or rod reels. (Something that I have also seen increasing in the past two years- Report #5, July 9, 2012, Clinton) that would make sense as the bait is strong on the ring as also a hook (that hasn’t changed). And many of coastal small “boat” fish was still caught by hand lines (rod and reels were just too expensive except perhaps for the summer visitors) and the hook just made larger to accept more bait? The mention that they were held to feel the bite was just the same as any bait and hook except there was no way to really hook the crab.
In fisheries history a baited line is frequently described as a “gorge” where bait was strung on a piece of flat bone or wood. In fact, the use of baited lines (no hooks) is attributed to the first fishing gear, and survives today as an eel bob, a ball of twine on to which worms are strung on thread (if this sounds laborious, it is) and lowered to the bottom; eels bite the worms and “ball” and they get their teeth snarled in the ball of hidden string enabling fishers to quickly haul them from the water. A hand line bait is also described as a way to catch lobsters. In Europe, lobsters grab the ring and are hauled up to the surface slowly and dip netted (Finland, Norway).
If this sounds familiar to blue crab killie rings it should; it describes the same method to catch blue crabs. Some could argue that these were perhaps the first fish gear (other than hands). But the practice has continued into “modern” times and is mentioned in some crabbing books. In successful crabbing Ernest Cottrell et al (1976) describes making one as the better hand line on page 29.
“To make a better hand line, you will need a piece of stiff stainless-steel wire, such as piano wire or heavy fishing leader, about 20 inches long, a sinker with a connecting link, a swivel, and a piece of plastic tubing three or four inches long. Using wire to one side of the swivel, then attach the connecting link with the sinker to the same point. Next, put the piece of plastic tubing on the wire and push it up near the swivel. The plastic tubing should be slightly larger than the wire, so that when the loose end of the wire is pushed in, it will fit snugly. Finally tie the line to the other side of the swivel, and the hand line is complete. (Choose your line length and sinker weight as described for the simpler hand line.)
This stiff wire hand line works well with all kinds of bait; it is also very easy to remove the bait when one is finished crabbing for the day.”
This method was very similar to the green floral wire example I saw at the DEEP Baldwin Bridge (Old Saybrook) fishing pier this summer with fish not killies and what makes this hand line work, is a relatively dense crab population. The crab population needs to be fairly dense to have such a basic fishing method remain successful.
The practice however is an old one—in a section on edible crabs Richard Rathbun wrote in 1881, “In deeper water it is sometimes customary to entice the crabs to the surface by means of a bait attached to cords (twine) pg 777 and later that “in early spring they are trolled from deep water to within reach of a dip net by means of a piece of meat attached to a long string.” He further offers an explanation why blue crabs have no “market” except near large cities in 1880—the reason being they can be so easily pursued as to local abundance that crabbing yourself satisfies any commercial need. He also mentions that torch lighting blue crabs at night had become an evening ”sport” in southern states, and leads one to believe that blue crabs then were indeed abundant.
Much later in Fish Catching Methods of the World, by Andres von Brandt (1964) states baited lines are the first “gear” to catch fish, from a Native American gorge – a thin bone upon which bait is threaded attached to a piece of twine, once swallowed and twine pulled, the fish has literally a “bone in the throat” and perhaps the first primitive hook.
The use of bait on a string is worldwide and is practiced not only in commercial fisheries but also in sport fishing crustaceans and mollusks besides fish are caught in this manner…” Lobster fishing at night (Finland) a line with a small sinker and sufficient mussel meat from a cataman to the bottom of the fishing ground. As soon as the bite of a lobster is felt, the line is hauled up very slowly and the lobster is caught with a scoop net before reaching the water surface.” A variant of this method continues in Hawaii today, where a bait marked by a float is put on the sea bottom to catch crabs and hauled carefully with the help of a scoop net (pg 67).
If this sounds familiar to our primary recreational crab gear, it should, as it perfectly describes the method we use today. This method is certainly low tech, cheap and allows quick access to the fishery and when crab populations are dense effective, it works.
I think most everyone will agree that this method also has a low catch efficiency, at least from my perspective.
The killie ring therefore may represent a combination of several bait “lure” representations rather than just chemical bait signatures in the water; the smelly bait concept. But the use of live bait that may have presented a known species that lived with blue crabs, such as Fundulus (chicken does not meet that criteria) and perhaps sight alone may trigger the approach, a shinny flash of killifish could be more than chemical clues, because more often than not was alive thus it really was a crab “lure” and not a crab “bait” and as a lure, needed to be hand held which appears to be the practice. If I have time this fall, I will try one or two and report back, also if anyone still uses a true killie ring, drop me a line- I would be interested in some perspective on this very old crabbing method.
Western Crab Reports Offers Promise
Some of the late August and early September reports mentioned large numbers of 1 to 2 inch blue crabs moving into shallow coves offers promise of a better western blue crab season next year. For the eastern areas the number of 1 to 2 inch crabs was down sharply. Western areas recovered late July from nearly two years of poor crabbing (Report #14, August 19, 2011). It is thought that a tremendous amount of watershed leaves and organic matter (Report #7, 2013) was washed into the lower rivers and hot temperatures eliminated them. Earlier this summer several crabbers commented about the increase of leaves and bubbles rising from them (Report #3, July 23, 2013). Eventually dependent upon energy waves and tides this organic matter is eventually dissipated, broken down by shrimp, other organic grazers and reducing bacteria. If oxygen is present, habitats should “recover” quicker, the leaves and organic matter melts away. If oxygen is limiting the organic matter will take longer to disappear, one crabber described it as several feet of leaves on a lawn, and waves and tides were a leaf blower. We don’t know how many crabs were eliminated in July 2011, but areas that had large numbers of crabs were greatly reduced (Report #6, July 19, 2102 and Report #1, April 17, 2013 ). The 1 to 2 inch size should represent a strong 3 to 4 inch year class next season and offers those western crabbers an early good spring season.
Email blue crab reports to: tim.visel@new-haven.k12.ct.us
All blue crab observations are valuable as we learn more about our blue crab population. 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.
Program reports are available upon request.
For more information about New Haven Environmental Monitoring Initiative or for reports please contact Susan Weber, Sound School Adult Education and Outreach Program Coordinator at susan.weber@new-haven.k12.ct.us
The Sound School is a Regional High School Agriculture Science and Technology Center enrolling students from 23 participating Connecticut communities. |
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