A crab pot holds a captured blue crab. Between 600,000 and 800,000 pots are fished each year, and 12–20 percent are lost. (Dave Harp photo)[/caption] When Virginia closed its winter dredge fishery in 2008, waterman Clay Justis turned his attention from catching crabs that season to collecting the gear that captures them. He was one of several watermen hired under a program that taught them to use sonar to find and remove lost and abandoned fishing gear, primarily crab pots, littering the bottom of the Bay. “As a waterman, I knew there was stuff on the bottom, but when I turned the machine on, I was like, ‘Wow!’” said Justis, who fishes out of Accomack on the Eastern Shore. The sonar showed that out of sight in the Bay’s often murky water, crab pots lay scattered all over the bottom, along with other fishing gear such as gill nets, and all manner of trash, even a laundry machine. But the so-called “ghost pots” are a special concern because the wire mesh cages with openings to draw crabs in but not let them out can continue to catch — and kill — crabs and fish for years. They are taking a bite out of both the crab populations and the wallets of watermen. More often than not, Justis noted, the derelict pots he pulled up had something in them. “You’ve got fish, you’ve got crabs, and you’ve got ducks. All kinds of things,” he said. But, he added, “most of the time, they are dead.” Concern about derelict crab pots in the Bay has been growing for a decade, and a new report attempts to estimate their Baywide impact. It estimates that more than 145,000 pots litter the bottom of the Bay — a number the report authors consider to be conservative. Each year, the report estimated that those pots kill about 3.3 million crabs, 3.5 million white perch, 3.6 million Atlantic croaker, and smaller numbers of other species, including ducks, diamondback terrapins and striped bass. The number of crabs killed amounts to 4.5 percent of the 2014 Baywide harvest, the report said. Nor is the problem limited to the Bay. Studies have found similar problems with fisheries that use “trap” devices to catch crabs and lobsters globally. “It’s an issue that, around the country, folks may not be aware of unless you live close to an area where commercial fishing is a way of life,” said Amy Uhrin, senior scientist with the National Oceanic and Atmospheric Administration Marine Debris Program, which funded the study. “It is one of those ‘out-of-sight, out-of-mind’ issues.” Financial impacts of lost pots The report said impacts from lost pots could be reduced through collection programs and by requiring panels in pots that would degrade and create an escape hatch for crabs if the pot is left in the water. It also suggested trying to reduce conflicts between crabbers and boats, which is a major source of pot loss. Justis said the lost pots are an ongoing problem. “Each year, even if you go back to the same spot, a lot of times you find new stuff.” Nor is it just crabs and fish that suffer from lost pots. Watermen take a financial hit, too. Baywide, 12–20 percent of the 600,000 to 800,000 pots they fish annually are lost and never come out of the water, the report estimated. Fishermen collectively have to shell out $3.6 million to $5 million a year to replace the lost gear, it said. But lost pots have an even bigger economic impact by reducing catches in nearby pots. Crabs are attracted to structures, including derelict pots, even if they’re so damaged or broken they no longer trap crabs. Crabs hanging around the abandoned gear don’t make it to the pots being actively fished. “The derelict pots are essentially competition for the active pots,” said Donna Marie Bilkovic, a researcher at the Virginia Institute of Marine Science, and lead author of the new report. “The crabs are definitely attracted to the structure.” In “hot spots” with lots of derelict pots, the fishery becomes measurably less efficient, said Andrew Scheld, a VIMS fisheries economist who worked on the report. “It requires more people and pots to catch the same amount that they could if the derelict gear just wasn’t out there.” The study was not able to directly estimate the economic impact of the lost pots on catches. But conversely, it found that crab catches increased in areas of Maryland and Virginia where derelict pots were removed by watermen like Justis, when compared with areas where pots were not removed. Based on that, scientists estimated that removal programs increased cumulative crab catches in those areas by slightly more than 38 million pounds from 2008 to 2014. That was worth about $33.5 million over that six-year period. Scientists from the NOAA Chesapeake Bay Office discovered the derelict pot problem when they began detecting large numbers of pots as they were using side-scan sonar to map bottom habitats during the winter — long after crab season had ended. While other types of fishing gear, such as gill nets, are also lost, crab pots are the main derelict fishing gear in the Bay because so many are deployed — and lost. When a severe decline in the blue crab population prompted NOAA’s National Marine Fisheries Service to declare the Bay’s fishery a failure in 2008 — spurring new catch restrictions and the closure of Virginia’s winter dredge harvest — it provided $30 million to Virginia and Maryland for conservation projects. Both states used some of that money to hire watermen hard-hit by the new regulations to pull thousands of abandoned pots out of the Bay. Crab pots are typically baited with dead fish to lure crabs inside, then placed in the water, where they are typically checked every day or so. They have “cull rings” that allow small crabs to escape, but large crabs are trapped. Watermen mark their pots with small buoys that float on the water’s surface. But if the lines linking the pots to the buoys are severed, they often cannot find the gear. Sometimes the lines break. Frequently, the lines get snagged and tangled in the propellers of recreational or commercial boats, prompting boaters to cut them. Some are lost in the violent winds and waves of storms. More than 100,000 pots disappeared during hurricanes Dennis and Floyd in 1999. And, sometimes, old pots are simply discarded in the Bay. The report estimated that Virginia had 87,048 derelict pots and Maryland 58,185. More are lost in Virginia, researchers say, because the state permits pots to be placed in Bay tributaries, where they are more likely to run afoul of boats. Maryland does not allow crab pots in tributaries, though pots are densely deployed near their mouths, where heavy boat traffic accounts for derelict pot “hot spots” in those areas, the report suggests. Lost pots ‘ghost fish for years’ However they are lost, pots that remain in the water can keep “ghost fishing” for crabs and fish, sometimes for years, until they begin to fall apart. Once the original bait is gone, traps often “self-bait” by trapping fish or crabs inside, and the cycle continues. On average, a derelict pot in the Bay catches 23 crabs a year, the report said. Besides crabs, more than 40 species have been found in pots where they can perish from starvation, predation, low dissolved oxygen or disease. Unlike actively fished pots — they’re not checked so turtles and other species are never set free. In some Virginia tributaries, crab pots have been suspected of depleting local populations of diamond backed terrapins. “One year, I pulled a pot that had 20-some turtles in there,” Justis said. “They were all dead.” Scientists working on the study said that derelict crab pots are likely even deadlier than they reported. In part, that’s because for the study, they assumed that lost pots only function for two years before they fall apart from corrosion. But many stay intact much longer, especially more expensive pots where the wire mesh is coated with vinyl. Ward Slacum, a co-author of the report who has studied derelict crab pots in Maryland for nearly a decade, said he once placed pots in the Bay for 14 months to see what they would catch. “When we took them out and cleaned them off, they had not degraded very much at all,” Slacum said. They were “trapping crabs and other organisms just as efficiently as something that was a month old.” Also, the study did not examine the impact of ghost pots in habitats where crabs are particularly abundant, such as underwater grass beds and marsh edges. “We think we’ve underestimated that potential impact with those habitats,” Bilkovic said. Solutions won’t be easy