Thursday, July 20, 2017  

Ghost Hunt on the Bay


Virginia watermen place nearly 350,000 crab pots into the Bay and its tributaries every year. Of those, upwards of 20% will be lost yearly, creating an astonishing debris field that poses a safety, nuisance, and environmental hazard to not
only blue crabs but dozens of other creatures as well.

By Deb Weissler

It was the second crab pot buoy I had found washed up on Haven Beach in less than a month. Somewhere out in the Bay two more crab pots joined the thousands of others sitting on the bottom. Except for the waterman, whose investment in the pots is now likely lost forever, or the scientists who study them, to most of us it is quite frankly out of sight, out of mind. Few realize that though now derelict, these lost or abandoned pots continue functioning, luring crabs and other marine life inside; efficient killers whose catch will never make it to market.

The density of derelict or ghost pots varies by region depending on fishing pressure, recreational and commercial boating traffic, exposure to large fetch, and storm impacts. In areas around Tangier Island, the York River, and along the Eastern Shore, there can be a dozen lost pots per acre. Poor choice of buoy materials, worn lines, abandonment, and vandalism also contribute to this growing problem.

Virginia watermen place nearly 350,000 crab pots into the Bay and its tributaries every year. Of those, upwards of 20% will be lost yearly, creating an astonishing debris field that poses a safety, nuisance, and environmental hazard to not only blue crabs but dozens of other creatures as well.

Dr. Kirk J. Havens, Director, Coastal Watersheds Program at the Virginia Institute of Marine Science, College of William & Mary puts it quite simply. “One crab pot lost at the beginning of the season can capture 50-100 market-sized crabs over the season.” As the marine life trapped inside dies, it serves as bait, enticing others that fall victim to a vicious cycle that does not end until the pot eventually corrodes away.

In areas of the Bay with high salinity a derelict pot begins to break down after a couple of years. In brackish waters, pots, particularly vinyl-coated ones, tend to last several years. The design of the modern crab pot is simple but effective, enticing crabs to enter and preventing their escape.

Prior to the use of pots, blue crabs were caught using drop lines or trot lines, a heavy fishing line with baited hooks attached at intervals by means of branch lines called snoods. Northern Neck’s Benjamine F. Lewis patented the first crab trap in 1928 but it was not well received among watermen, who claimed the design allowed crabs to escape too easily. His revised trap patented in 1938 was a huge success and by mid century the use of pots spread throughout the Southeastern and Gulf fisheries.

In general, a crab pot consists of a cube of wire mesh, galvanized or vinyl coated, with two funnel-shaped openings on opposite sides, bait located in the center, and a horizontal divider with openings leading to an upper chamber. An iron reinforcing bar in the bottom provides stability and some watermen add zinc anodes to inhibit rusting.

 From mid March through November crab pots are placed throughout Bay waters with the exception of navigable channels with government-installed navigation aids or in any portion of a government-marked channel of a river, bay, estuary, creek or inlet. Blue crab spawning estuaries are banned from crabbing from May 1 through September 15.
Pots are currently marked with floating buoys or stakes with a waterman’s identification number burned in. Currently there are no uniform buoy colors required for pots in the Bay as is required of crab and lobster pots in New England waters where buoys must be painted with licensee’s approved color scheme and watermen must prominently display the licensee’s buoy colors onboard.

Bay watermen have tried a variety of painted buoys and buoy designs over the years with little success. Many complain that recreational boaters are not properly educated on how best to avoid crab pot buoys and lines, or what to do in the event of a collision with one. Many navigation maps and cruising guides fail to mention areas where heavy pot concentrations make avoidance nearly impossible. Each collision adds another ghost crab pot to the growing number littering the Bay.

VIMS first observed the proliferation of lost pots in 2005 while using sonar to map various sediment types on the Bay floor. Numerous square objects proved to be lost or abandoned pots without buoys. VIMS partnered with the National Oceanic and Atmospheric Administration’s (NOAA) Marine Debris Program to better understand the issue.
To determine the extent of the problem NOAA provided funding that allowed VIMS to survey an area of the York River just south of the Coleman Bridge in Gloucester County, an area of about thirteen square miles or 8,278 acres. The findings were eye opening.

VIMS located 676 lost pots (about 52 pots per square mile or 12 pots per acre.) But it was what they found trapped inside those pots that proved so disturbing. In addition to blue crabs there was a large number of Atlantic croaker, oyster toad fish, and white perch.

It soon became clear that derelict traps were having a significant impact on sensitive habitats, and continued to trap both blue crabs and other bycatch species-- black sea bass, spot, striped bass, flounder, diamondback terrapins, eels, even ducks and small mammals, leading to high mortality rates that can continue unabated for years. Animals captured in derelict pots die from starvation, cannibalism, infection and disease. The economic loss alone is incalculable.

In 2008 the governors of Virginia and Maryland, alarmed at the decline in peeler and soft crab harvests, requested the US Department of Commerce to study the causes of this commercial fishery decline. In response to the federal declaration, the Virginia Marine Resource Commission (VMRC), the state regulatory oversight, developed a Blue Crab Fishery Resource Disaster Relief Plan. As one part of the plan, then Virginia Governor Tim Kaine approached VIMS and VMRC to develop a plan to employ commercial watermen directly affected by the closure of the winter crab dredge season, to locate and remove derelict pots from Virginia waters.

The program began in 2008 with 58 watermen working 48 days, plus one day of training using sophisticated side-imaging sonar equipment and a second day constructing mounts for the sonar transducers and pot recovery devices. Watermen ran a grid pattern, mapping the bottom, spotting potential targets, and noting their GPS coordinates. They returned on another day to retrieve those objects that were then identified, photographed, and recorded. All live bycatch was released. Participants were paid $300 a day plus $50 a week for incidentals. By 2011, there were 70 participants with 24 days on the water. During that time a total of 34,045 items were removed from the Bay.

David Stanhope, VIMS Field Research Manager, Center for Coastal Resources Management, shakes his head in amazement at the types of items retrieved during those four years. “In addition to derelict pots, we found lawn chairs, boats, tires, fishing gear, appliances, even baby strollers.” For centuries the Bay has been carelessly treated like a dump and here was proof.

If there was a positive spin on all this activity, watermen noted that more than 600 pots had significant oyster growth, evidence that derelict pots, if properly disabled, would make ideal habitat for oysters by elevating them off the bottom and providing shelter from predators. One pot had been in the water so long an impressive seven inch long oyster had developed.

Sadly the program ended March 2012. Locating and removing lost pots is costly and time-consuming and, with a never ending supply of derelict pots, any hopes of removing significant numbers are unrealistic.

“While it may be helpful to find funding to employ watermen to remove pots from the Bay’s “hot spots”, Dr. Havens explains, “it will be difficult to find funding to continue the program on a large scale. VIMS will work with watermen to provide long-term loans of side-imaging sonar units so that they might be able to immediately recover their own pots lost during the season.”

Kory Angstadt, VIMS Marine Scientist, Center for Coastal Resources Management, is excited about the results of testing a biodegradable escape panel made from corn that would gradually desolve over the period of a year, rendering the pot ineffective. Mandating such panels would require a change to VMRC’s regulations however, a time-consuming process that would include a public hearing and take into account any economic impacts.
In the meantime it would be helpful if recreational boaters were made aware of where pots are deployed and how currents, winds, and tides can affect buoy and pot positions. Boaters should be taught what to do if they catch a pot on their prop instead of cutting the line, sending it to the bottom to become another statistic.

Special thanks to Dr. Kirk J. Havens, David Stanhope, Kory Angstadt, and Karen Reay at the Virginia Institute of Marine Science.