‘An invisible killer’: how fishing gear became the deadliest marine plastic
Plastic in the depths: as ‘ghost gear’ chokes the ocean, campaigners call for mandatory measures including buy-back schemes and recycling
A trip to the remote north Pacific gyre provides a stark reality check on the scale of the planet’s plastic waste crisis. “You’ve been sailing at 10 knots for five days, you’re alone. You don’t see any other boats. And then you find toothbrushes and lighters floating around you,” says Laurent Lebreton, head of research at the Ocean Cleanup, a Dutch non-profit organisation that develops technology to extract marine plastics. “It’s just very surreal.”
What he finds most striking, however, are the metres of netting, ropes and line, luminous orange buoys, crab pots and fish traps: remnants of the global fishing industry, drifting around in what is known as the “great Pacific garbage patch”.
From samples gathered by the Ocean Cleanup’s floating boom system – which rakes in plastic from this swirling gyre – Lebreton’s new research deciphered clues on some of the plastic fragments, which suggest that most of that waste can be traced back to five industrialised fishing nations: the US, Japan, South Korea, China and Taiwan.
Typically, the finger of blame for marine plastic is pointed at terrestrial pollution from rapidly developing economies in south-east Asia and elsewhere, Lebreton says. But his fresh discoveries highlight the contribution of industrialised nations to this problem, too.
Known officially as abandoned, lost or discarded fishing gear (ALDFG) – and unofficially as “ghost gear” – this marine waste comprises fishing nets, ropes, line, traps and other fishing paraphernalia, mostly made up of durable plastics. Highly buoyant plastic fishing gear is more likely to become concentrated in places such as the north Pacific gyre, but it is also dispersed across the ocean. The quantity is notoriously difficult to measure, but it is estimated that between 500,000 and 1m tons a year tumble into the seas.
An October survey of 450 fishers from seven big fishing nations estimated that 2% of fishing gear used globally ends up in the ocean. The share may seem small but the scale of global fishing is enormous, says Kelsey Richardson, the lead author on the study.
It amounts to an estimated 3,000 sq km of gill nets, 740,000 km of longline mainlines, and 25m pots and traps. At the current rates of loss, the amount of stray fishing nets measured by area would be enough to carpet the surface of the planet in 65 years, the researchers found.
“Unfortunately, wherever fishing takes place, gear is being lost,” says Ingrid Giskes, director of the Global Ghost Gear Initiative, a programme spearheaded by the Ocean Conservancy that brings together fishers, conservation organisations, industry players and governments.
Ghost gear contributes about 20% of marine plastic – with most of the rest coming from land-based sources – but underwater, its effects are profoundly worse. “It continues to operate as something that catches marine wildlife,” says Christina Dixon, ocean campaign leader at the Environmental Investigation Agency. “It’s an invisible killer.”
The World Wide Fund for Nature calls fishing waste the deadliest form of marine plastic, finding that entanglement or entrapment by ghost gear affects 66% of marine animals, including all sea turtle species and 50% of seabirds.
Captured animals die due to suffocation, drowning and starvation, or because they are left unable to properly breed and migrate. “Everyone knows that video of the turtle with the straw in its nose, but kilometres of gillnets are way more deadly,” Giskes says.
Different types of ghost gear can form giant masses – such as the 9,000kg ball of jumbled rope, nets and line that the Ocean Conservancy helped fishers haul up from the seafloor off the coast of Maine in 2019. It was “floating beneath the surface, out of sight”, Giskes says. These layers of waste can pose navigational hazards and crush ecosystems such as coral reefs and seagrass meadows, creating barriers and stifling marine life.
All the while, ghost gear is costing millions of dollars to clean up, especially for small island nations that lie in the path of drifting gear that invades their reefs and beaches, Dixon says.
There are many reasons fishing gear ends up as marine waste – from stormy weather to poor storage and gear snagging on the seafloor. Fishers facing tough economic conditions may take more risks to catch fish, says Richardson, increasing the likelihood of damaging or losing gear. The especially risky conditions around illegal fishing mean that this shadowy phenomenon is probably contributing even more to the waste.
Whatever the scenario, “the majority of the loss is not because fishers throw gear overboard. It’s unintentional,” Giskes says. Equipment is often expensive to replace. Warren Unkert, a commercial crabber in New Jersey, says he loses about 30 crab pots annually, and at $40 (£35) a pot plus lost catch, the costs mount up.
Where exactly ghost gear comes from is still under-researched. Lebreton’s study traced the national origins of fishing waste in the great Pacific garbage patch (which pointed, logically, to countries with the greatest fishing presence in that ocean) – but it does not tell us much about the other regions, he says. “I’d be curious to know what we’d find in the other [four] gyres.”
To plug these knowledge gaps, the Global Ghost Gear Initiative is drawing together data from government members and fisher surveys to create what Giskes expects will be the largest global dataset on ghost gear. In the next five or 10 years, they hope to have a comprehensive picture of the problem.
In the shorter term, there has been innovation aiming to tackle ghost gear. Designers have developed biodegradable fishing gear and satellite-traceable buoys that allow fishers to track and retrieve lost traps. Gear recycling is now commonplace in several ports, and a handful of these include gear buy-back schemes for old or damaged gear.
In the US, the National Oceanic and Atmospheric Administration’s Marine Debris Program funds dozens of prevention and retrieval projects: one of these has partnered with the New Jersey-based Stockton University with fishers including Unkert to identify sunken crab pots using sonar off the state’s shoreline. “We’ve gotten at least 5,000 or 6,000 off the bottom, from one small bay over the last 10 years,” Unkert says.
Canada has made it mandatory to report gear loss, as well as to mark certain gear, which makes it possible to trace lost gear back to individual vessels and nations, and is thought to increase accountability. Some momentum is building on the industry side too: Thai Union, one of the largest seafood companies in the world, requires its tuna suppliers to mark the non-biodegradable parts of fish-aggregating devices, says Adam Brennan, the company’s group director of sustainability.
But efforts to tackle ghost gear have so far been piecemeal and mainly voluntary, which does not fit the enormous scale and transnational nature of the waste, Dixon says. “Fishing gear has really been falling through the gaps of global governance.”
This may change with the legally binding international treaty to end plastic pollution, which will be drafted by 2024. Negotiations on its terms, which start this month, provide an opportunity to make measures to tackle ghost gear – such as gear-marking, buy-back schemes and designing recyclable gear – mandatory across all nations. Most solutions are “only really going to be effective if everybody is doing it”, Dixon says.
There is a way out of the tangled mess of ghost gear if governments are willing to come together, Giskes says. “This does feel like a solvable problem.”
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