CTFishTalk.com: CT Blue Crab Report 7 - first section - August 9, 2012 - Connecticut Saltwater ( CT Saltwater ) - A Community Built for Connecticut Fisherman.

BlueChip

The Connecticut Blue Crab Population 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 7 – August 9, 2012
You Do Not Need To Be A Scientist To Report!

• Crabbers move to deeper cooler waters – boaters seem to do better – Central CT crabbing shifts as summer temperatures rise.
• Dipping for crabs by torchlight, Noank, CT at the turn of the century; Blue Crab Skiff Plans available soon.
• Keep those crabs alive! The knuckle bander process. Crabbing surges in central Connecticut.
• Regional differences become apparent – concerns for Megalops set in Western, CT.

Crabbers move to deeper, cooler waters

Most of the crab catches from shore now occur at high tides: two crabbers commented, “It’s getting too warm- water temperature.” A couple of crabbers last year reported a change over from place to deeper areas when water temperatures hit 72⁰F; after that they used a small skiff with crab pots.

Central CT catches at low tide decreased measurably and many small crabs are caught then. This was especially the case in the Clinton/Madison area which saw the numbers of just 5 inch crabs suddenly increase; many were still too “short”. A Clinton Harbor crabber retained 23 crabs, but estimated he had returned over 50 small crabs. Dozens of small 3 inch crabs were observed at both the Oyster and Indian Rivers; crabbers at the pier next to the Baldwin Bridge DEEP boat launch also commented about the dramatic increase in small crabs. Obtaining the “bottom” temperatures seemed like a good idea, especially if the 72⁰F temperature is a border line perhaps for larger crabs. A slight modification to an inexpensive thermometer and a crab line with a 2 ounce sinker gave me a quick way to check some temperatures at some popular blue crab locations over the weekend.

Saturday, July 28 – Temperature readings.

Essex Town Dock Deep end – 6 feet, low tide 79⁰F: 11:40 a.m.
Essex Town Dock Shallow – 1 foot, low tide 79⁰F: 11:50 a.m.
Rt. 95, Baldwin Bridge, Old Saybrook; DEEP Fishing Pier, shallow end 78⁰F: 12:01 p.m.
Old Saybrook, Sheffield St. Town Dock (North Cove) 75⁰F 1:02 p.m. (DLW)
Old Saybrook Route 1, Oyster River Dredge Cut 74⁰F 3:24 p.m. DLW+ 2hours
Westbrook Town Dock, Hammock Rd 72⁰F 3:38 p.m. mid tide
Clinton Public Crab Dock, Indian River 74⁰F 4:28 p.m. high tide
Clinton Town Dock Riverside Ave. (Hammonasset River) 72⁰F high tide

Catches in the 72⁰ to 74⁰ range were better than higher; Essex crabbers left with no crabs at low tide; I was surprised to see how warm it was. However, high tide was a completely different matter with 7 and 8 inch crabs at high tide.

About the middle of August last year, crabbers moved to deeper cooler waters, but with this year’s heat, we may be seeing that shift earlier. The warmer temperatures did not seem to bother the two inch crabs which surrounded shallow water baits. Crabbers that had baits into deeper areas commented that it was better at high tides. It’s thought that cooler waters come in with the tide, and cooler temps, higher salinities, and perhaps increased oxygen levels help adult crabs’ more than the smaller ones. Crab respiration increases with temperature, a rise of 10⁰ C, the respiration roughly doubles; in other words, a respiration rate of 68⁰ F is twice that at 50⁰ F. Warm water contains less oxygen so the perception (observation) that larger crabs move to deeper cooler waters has a basis in biological fact. Seawater at near freezing can contain 12 mg of oxygen per liter of water, but at 86⁰ F can drop below 5 mg/liter. Extremely high temperatures can kill marine organisms by suffocating them. I see some first time crabbers trying to keep large 7 and 8 inch crabs alive in a small pail of warm water. Occasionally many of the crabs perish in such small amounts of hot seawater, and frequently suggest a cooler with an ice pack keeping crabs cool and moist rather than in small water pails. It’s a frequent mistake but directly related to warm water suffocation on a much wider scale; we usually call such widespread events as die offs and frequently they occur during the hottest period of summer water temperatures. Crabs (and lobsters) have the ability to alter metabolic processes out of water if kept cool and moist can survive for many hours and if given the choice will avoid such oxygen containing water. These warm water die offs are frequently found in the blue crab historical fisheries literature.

In Alabama and even in Chesapeake Bay, extremely low oxygen in coastal waters often records blue crabs walking out of them, sometimes by the hundreds of thousands. In southern areas this event is known as “Jubilees,” thought to reflect the ease in capturing a potential dinner. In the Chesapeake they are known as crab wars. When faced with extremely low dissolved oxygen, blue crabs emerge and can crawl out of the water (Blue Crab- Callinectes sapidus by William F. Van Heukelem, University of Maryland).
A mini “Jubilee” occurred in Connecticut a few years ago noticed by residents of Niantic Bay during very hot period in August. Stagnant hot algae filled water became oxygen depleted. Blue crabs headed for land in apparent effort to escape the low oxygen waters and died in the process. The account is in the WTNH (Channel 18(archives with the title: “Crabs Picking Land Over Niantic Bay”. On August 7, 2009 this was reported by Jamie Muro from the description of Niantic River algae blooms and reported air temperatures; it’s a safe bet that hypoxia killed blue crabs in shallow water.
Connecticut River crabbers (pots) now report very good catches and crab floats – pier areas have been good also. The shore hand liners, catches at low tide here have been much lower than at high waters – Central CT crabbing has been generally good, better than last year. The large increase in small 3 to 4 inch crabs is a positive sign for even a better fall fishery.

Dipping Crabs in Noank at the turn of the century – Nighttime netters from small skiffs count crabs by the bushel.

12 ft Blue Crab Skiff Plans available soon from The Sound School

Numerous accounts from the turn of the century (pg 645, The Crab Fisheries US Fish Commission Bulletin, 1887) talk about dipping crabs by torch light in a two person row boat. A small skiff with a forward torch and dipper with a rear sculler, a single oar mounted to a pin or leather strap. This allowed the boat to be propelled quietly from the stern (sculling) while allowing the person forward to have a clear view to net crabs (the water must have been a little clearer back then). The coves and shores of Noank 1920s are frequently mentioned for catching blue crabs from flat bottomed skiffs. These skiffs were often low profile craft that could be both rowed- two oars or skulled with one rear oar. Sculling itself was quite an art but having watched a couple of fishermen do it, it was quite effective, especially in shallow water. You could push and direct the skiff quickly from the transom, often standing, to see what was ahead and receive signals from the “dipper” in the bow. Several late summer dock conversations the past two years had crabbers wishing to reach the deeper and cooler waters of late summer to catch crabs, but unable to do so, for lack of a small flat bottom shallow water skiff. When asked about it, I’m partial to the Brockway design, a flat bottom plywood skiff once produced in Old Saybrook, CT. The Brockway skiffs originally were built to the design of the Connecticut River Duck and Turtle boats of the last century. They were low profile skiffs, excellent for duck hunting and setting and hauling turtle traps then.

But today the design survives for many fisheries, and sports fishing is one of them. Originally built as an oak frame planked skiff, at Brockway Boat Works of Old Saybrook, it was later changed the planked vessels and gave way to the plywood skiffs wide and narrow versions of various lengths. In the middle 1950s higher sides added to make them suitable for use in the open Long Island Sound. I used an old low profile (1959) Brockway in high school, a 12 foot skiff built in the tradition of the successful Connecticut River Duck and Turtle Boats (also called CT River Guide Boats as for use by hunting camps in the 1920s).

This skiff belonged to Charles Beebe, late of Madison, who continued to use it for river fishing until the 1970s. I have it now thanks to Bruce Beebe, and should have the design plans shortly. It is a transition skiff built in the old thwart and riser style but out of high grade marine plywood. As it is a low profile version it makes an excellent blue crabbing bay and cove skiff- sculled or rowed. Cost of a vessel has been a concern, especially in today’s times but this skiff can be built by a handy person requiring just a few power tools. It can be built from higher grade exterior A C plywood and standard pine stock from a lumber yard or home improvement store. Two larger high sided versions a 14 foot skiff and 16 foot skiff plans are already available on our website. Plans and directions, “How to Build a Brockway Style Skiff” were first published in 1982 and reprinted and can now be found on our school website: for the 14’ Brockway, #35 and corrections #36; the 16’ skiff at #40 and corrections #41. These skiffs are the higher sided version, not the low sided skiffs for the rivers and coves a century ago.

Many people have built Brockway style skiffs from these plans and pictures /plans are available at no fee. If you are interested in seeing what this vessel is like, one of the few surviving Connecticut River duck and turtle skiffs can be found at Essex, CT. During the Great Heat 1880-1920 warmer winters and unusually warm springs caused a surge in game bird populations – geese, rail and brant duck (bird) hunting became big business as out of state hunters turned to local fishermen to guide them into the Connecticut River marshes.