Abandoned fishing nets and pots, trap, maim, and kill hundreds of marine animals daily
Unseen below the surface, fishing gear reaps the oceans bounty the world over. Viewed from below, nets appear as veil walls lightly dancing the currents with a serene and silent intent. Ever since nets began to be cast out at sea eons ago, more and more fishing gear has been entering our oceans daily. And much of this gear remains in the water — lost, torn away, or simply abandoned.
Photo by Tim Sheerman-Chase/Wikimedia CommonsSome
abandoned nets and lines wrap themselves on reefs, shipwrecks, or rocks, ensnaring marine animals, maiming, drowning or simply starving hundreds of thousands of them.
Abandoned fishing gear devours sea-life with insatiable hunger. To a number of conservationists, these derelict nets are darkly referred to as “ghost gear.” In more technical terms, it can be called Abandoned, Lost, or Discarded Fishing Gear (ALDFG).
ALDFG functions in a number of ways. Floating nets wander around, collecting a plethora of organisms, and eventually sink under the weight. As this biomass breaks apart in the ocean’s benthic regions, the nets shake their load and lumber upwards again, ready to wreak more havoc. Some nets and lines wrap themselves on reefs, shipwrecks, or rocks, ensnaring marine animals, maiming, drowning or simply starving hundreds of thousands of them. Pots intended for crab, lobster, and shrimp see an eclectic range of visitors. Entire crab or lobster lineages, scavenging bottom dwellers that venture inside for a hapless predecessor’s remains, perish in these traps.
Abandoned gear makes no distinctions, capturing marine mammals, fish, turtles, whales, birds, sharks, rays, and invertebrates.
To combat the problem, an organization called Ghost Fishing arose from a hardy band of clean up divers in the North Sea. The group started out clearing shipwrecks near their native Netherlands. Now, it’s grown into a global network of cleanup groups..
Cas Renooij, director of Ghost Fishing, explains how the organization began. “About five years back some people in the Netherlands started to clean up nets from wrecks. It turned into an environmental attempt to not just make the wrecks more attractive, but also to prevent fish from dying in those nets. Later in the process it [saving marine life] became a number one priority.”
Abandoned fishing gear has become a global problem. One report, jointly issued by the Food and Agriculture Organization and the UN Environment Program (UNEP), estimates that 640,000 tons of such abandoned nets are spread across the world’s oceans, comprising up to a staggering 10 percent of oceanic litter. In the Puget Sound alone, derelict fishing gear kills over a half million sea-creatures each year, according to a Northwest Straits Marine Conservation Initiative estimate.
Fifty or sixty years ago, nets were commonly made from biodegradable hemp or cotton. With the advent of synthetic, degrade-resistant materials such as nylon, nets now can remain active in the water for hundreds of years. Some plastics can remain in the marine environment for up to 600 years. When gear does finally break apart, further damage is done when marine animals eat plastic particles and polyurethane chemicals leach into the water.
After seeing the destruction wrecked by derelict gear, Ghost Fishing began reaching out for help worldwide. “We looked around to see if there were more initiatives like this in the world, and we actually found some. We also found out there was no connection between them. That’s why we came up with the Ghost Fishing network. We reach out to those groups to give them a platform to get stories told, and raise awareness for the problem. We did some research and found that it wasn’t just a local problem, but a global problem,” says Renooij.
“Depending on the area where we clean fishing gear, it’s a different situation everywhere,” says Renooij. The project’s has to date removed 4,500 nets, 3,081 crab pots, and 47 shrimp pots.
However, preventing gear being lost in the first place has proven far less expensive than retrieval from the depths. Washington State, for instance has to spend approximately $190 to retrieve a single crab pot.
Photo by Courtesy of Doug Helton/NOAA A sea turtle entangled in a ghost net.
Since 2010, the Olive Ridley Project freed and rehabilitated 51 endangered turtles trapped or injured in nets inthe Maldives, illustrating how such gear puts added strain on an already endangered species.
Though fishermen are the source of ALDFG, they have perhaps the strongest investment in fisheries’ sustainability. Due to extremely variability in gear, regional conditions, and catch rates, and due also to insufficient data, it is exceedingly difficult to ascertain total catch killed by ghost gear. What data does exist, however, is liable to make fishermen listen. According to the California SeaDoc cleanup initiative, one abandoned net can kill $20,000 Dungeness crabs in one year. Removing the net costs $1,358. According to one study cited in a UNEP report, lost tangle nets catch around 5 percent of total commercial catch globally.
Unfortunately, there is little immediate incentive to use gear that is biodegradable. Polyurethane based nets became popular in fisheries largely because they were resistant to breaking down. Implementing new technologies that would reduce ghost gear’s longevity is vital to solving the problem. The difficulty lies in convincing fishermen to take on added expenditures and trips to the net shop.
“We are trying to walk to diplomatic route and convince [fishermen] to use biodegradable technologies,” Renooij says. There’s been some initial success with Dutch fishermen. “One success was switching lead weights to steel weights, it’s a definite change, not a hundred percent, but the awareness we need is starting to come up. And they are using lines that over time biodegrade, but the problem is it still takes a long time,” he says.
As with so many “tragedy of the commons” scenarios, the responsibility to act lies with everyone, and the incentive with no one. The 1973 International Convention for Prevention of Pollution from Ships is a start in curtailing marine pollution, but it does not adequately address the problem of ghost fishing gear.
Another area that needs attention is shoreline collection facilities. Whether due to barriers to access, unwanted costs, or downright absence of facilities, not enough used gear is making its way to shore. While it is difficult to build consensus and take action to clean international waters, fostering a sense of national stewardship could motivate people to repair coastal areas in their own countries and localities.
In the Gansbaai/Kleinbaai South Africa area there has been one encouraging development — DICT Beach Cleanup program that mobilize school kids to collect beach litter. This partnership between DICT and Volkswagen prove to be successful in creating awareness of this problem recently in a unique conservation effort. They built a life size wire whale and filled it with 534kg plastic during whale week.