Braving icy winds, choppy waters and frigid winter temperature, six teams of commercial crabbers have combed the muddy bottom of Great Bay the past few months in search of, well ... trash.

Over the years, their crab pots — wire cubes about the size of an old television — have piled up on the bay floor as bad weather or inattentive boaters chopped off the colored buoys that signaled where their catch lay. Thousands of these pots are somewhere in the bay, half sunk, full of debris, sitting there for years, sometimes creating a navigation hazard, sometimes dangerous to wildlife or the crabbers themselves.

What to do? Use technology to find the pots, fan out during the off season and pick them up. Along the way, take down plenty of information to help scientists map where the pots are found and what is inside when they pull them up.

And throw in a few thousand bucks to each crabber for their time and the promise of keeping whatever pot they pulled up.

Great Bay’s crabbers, like those working in other New Jersey waterways, each lose dozens of pots a year. Just because the pots are lying on the bottom of the bay doesn’t mean these “ghost” pots are benign. They can continue trapping aquatic wildlife for several years until release valves rust off or the openings are buried under mud. They also create a safety hazard for crabbers and boaters in shallow water. The crabbers can accidentally snag a pot.

The idea of an underwater litter pickup developed about three years ago, when Richard Stockton College professor Peter Straub and his marine technology students began finding what they thought were hundreds of derelict crab pots in the Mullica River and Great Bay, a short boat ride from the college’s Nacote Creek marine field station.

Just as the class was finding these “ghost” pots, a high-profile project in the Chesapeake Bay to remove tens of thousands of derelict pots made the news, said field station manager Steve Evert.

Meanwhile, crabbers Karen and Warren Unkert realized they were losing about 10 percent of their 600 to 700 pots every year. The couple, of Mullica Township, have been crabbing for 21 years and make their own pots every winter. Each lost pot on the bay floor meant about $10 in materials — or $40 if commercially made — and a potential hazard in the water that they think was lowering their catch, because crabs could be getting inside the lost pots and dying because they could not escape — a process known as bycatch.

“We said, ‘Somebody’s gotta clean this up,’” Karen Unkert said.

So the couple spent several thousand dollars to buy a side-scan sonar device. And just as they began to do their own project, the college called and asked if they wanted to be part of their project.

“When they got our letter, they were at my doorstep immediately,” Evert said.

The school received a $100,000 grant through the NOAA Community-based Marine Debris Removal Program for a two-year project. The grant paid for the crabbers’ time to recover the pots during the winter, survey work by the college, and outreach to the community along with the Jacques Cousteau National Estuarine Research Reserve. When the project is complete, Evert said, the school also will have developed a professionally produced DVD to train people around the country to do a similar project.

Before the pickup could start, Stockton professors, staff and students spent weeks surveying the bottom of the bay with a side-scan sonar detector, creating a map and list of GPS points for where a pot might be. Each crabber was then given an area in the bay in which to work.

On a late winter day, crabber Phil Andersen worked with his crew in a section of the bay about 2 miles south of Bradley Point in Little Egg Harbor Township. As soon as a GPS point was found, a crew member threw in a buoy to mark the spot. Another crew member then threw in a grapple line, and the boat circled the spot.

The grapple more often than not did not snag anything, but when it did, Andersen and crew member Bob Dinkelhopper hauled the line and heaved the seaweed and muck-filled pot into the boat. This was their 16th pot of the day, the last they worked before crabbing season opened March 15.

Of those 16 pots, eight could be cleaned up, Andersen said. Of the 491 collected during the winter in the Mullica River and Great Bay, 125 were cleaned up to be put back in the bay — a haul estimated to be worth about $5,000, Evert said. What pots couldn’t be reused were scrapped down into parts worth about $750, he said.

“These guys and girls have a serious commitment now to clean up the bay, hopefully increase their catches, and work with the scientific community to better the fishery,” Evert said.

Each crabber in the project will keep a sonar device on loan while they crab this summer, so if they lose a pot they can remove it quickly and not contribute to the problem, Evert said.

Warren Unkert said he was surprised at how long some of the pots had been in the water, and some that had been buried in the mud were almost like new.

“We were pulling up pots that we could estimate were over 10 years old, still in the water,” Warren Unkert said. “That’s a long time for these pots to be laying down there. It’s definitely not good for the environment. It’s litter.”

Contact Sarah Watson:

609-272-7216

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