Traps & Dredges

While not exactly shipwreck artifacts, lobster traps, scallop dredges, and other fishing equipment are not uncommon sights on and around New Jersey shipwrecks.

Lobster Traps

modern wire lobster trap
A modern wire lobster trap - a common sight around shipwrecks.
modern wire lobster trap
A similar trap provides shelter for a Conger Eel. Note that the trap is wide open. If you find a lobster trap with no buoy line attached, then it is lost, and fair game to plunder. Otherwise, leave it alone - the lobster fishermen need to make a living too.
modern wire lobster trap
Modern wire-mesh lobster traps on a dock
old-style wooden lobster trap
An old-style wooden lobster trap - you don't see these anymore, except as decoration on people's lawns.

Shellfish Dredges

Scallop dredge
Shellfish dredges are used to harvest clams and scallops from the seafloor. Scallop dredges are relatively small and light, while clam dredges are usually massive, with equally heavy towing gear, and a commensurately large and powerful vessel to draw it.
Scallop dredge
Typical scallop dredging operation; clamming is similar. Modern dredges use water jets to loosen the bottom in front of the rakes, with the water pumped down from the boat to the dredge in a large hose. The dredge is raised and lowered with a steel cable but towed with a more elastic nylon line.

Dragger captains try to avoid getting their gear caught in underwater obstructions, and have long lists of numbers of places to avoid. However, not all snags are known, and new ones are often discovered the hard way. When a clam dredge hangs up on an old shipwreck, it is often just pulled right through. Many of our old wooden wrecks are simply torn apart this way. Even metal wrecks can be damaged, as was the subway car upon which all the furor was based. I once watched a hung-up clam boat pulling in all directions to free its dredge, like a dog wrapped around a tree. If a large, expensive clam dredge breaks free, it is usually recovered with divers, who reattach the tow line.

Smaller scallop dredges seem more likely to break free and be lost than clam dredges. Scallop draggers also seem to take more chances, towing closer to known obstructions, because that is where the scallops are. As a result, a number of old shipwrecks are decorated with lost scallop dredges. The only sunken clam dredges I know of went down with their ships, such as the Beth Dee Bob and the Adriatic.

Scallop dredge
Scallop dredge on the 120 wreck
Scallop dredge
It is perhaps 8 feet across. There is an identical one on the Granite Wreck.
clam dredge
A massive, cage-like clam dredge, drawn up onto its frame.

Marine life colonization of experimental reef habitat
in temperate ocean waters off New Jersey, 1996-2004

By Jennifer Resciniti and Bill Figley
November 2005

This investigation was partially funded by the Federal Aid to Sportfish Restoration Program

for the original paper, see here.


ABSTRACT

A biological colonization study of experimental reef habitats in temperate ocean waters off New Jersey was conducted over a 96-month period. A total of 145 different taxa of 9 phyla were identified within the experimental units, including 42 arthropoda, 37 annelida and 43 molluska. Individual organisms had an estimated mean abundance of 534,566 organisms/m2 of habitat footprint, including 105 fish, 4,639 crabs and 14 lobsters. Colonial organisms covered 87,554 cm2 of the habitat surface area. Mean total biomass of the organisms inhabiting the units was 84,175 g/m2, with blue mussel comprising 63 percent of the total. The carrying capacity of the experimental habitat for all species of marine life was about 152,801 g/m2. Predation accounted for an 80 percent reduction of biomass between surfaces exposed and not exposed to predators. There were no statistically significant differences in biological colonization rates of sessile epibenthos on concrete, rock, steel and rubber substrates. On an equivalent area basis, the biomass enhancement ratios of the experimental reef habitats over surf clam-dominated and polychaete/crustacean-dominated sand bottom habitats ranged from 35 to 1,124 and 2,773 to 3,200 times, respectively. A simplified, three-tiered reef habitat food chain consisted of 84.5 percent sessile/sedentary invertebrates, 11.0 percent mobile invertebrates and 4.5 percent juvenile and adult fish. The results suggest that complex reef habitats provide both attachment surfaces and refuge habitats that support a diverse and abundant marine life community.

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