'The sea is like a minefield': The web of illegal fish traps in Italy's Mediterranean

Off the coast of Sicily, Sea Shepherd and its volunteers are hunting down illegal fish traps and working with Italian authorities to crack down on this environmental crime.

The flat water melts into the teal-coloured sky as a former pilot vessel, the Sea Eagle, sails through the calm Tyrrhenian Sea surrounding the Aeolian Archipelago of Sicily.

The ship is operated by Sea Shepherd, an international marine conservation non-profit. Today, the team is searching for fish aggregating devices (FADs), man-made plastic structures used to attract fish. They float in the water, anchored to the seafloor, with hanging nets to catch fish. FADs made from plastic, without GPS tracking devices attached, are illegal in Italy.  

While listening to techno music, a group of volunteers uses a winch to detach one of the FADs from the seafloor. A large plastic container labelled "corrosive" emerges from the sea.

"The [techno] rhythm gives us the right energy," says James* (the crew do not wish to use their full names for safety reasons), a young Canadian volunteer who is running the operation and whose arms are covered in ocean-inspired tattoos. The volunteers work tirelessly to extract the plastic FADs from the sea and pile the tangled trash heaps into big bags. The retrieved plastic will be turned into plastic crates for sea turtle rescue operations.

FADs are used worldwide by fishermen to attract pelagic fishes into surrounding nets. These fish-trapping devices are typically composed of used fuel, pharmaceutical and other chemical containers among other types of plastic waste, dark plastic nets and rocks, all of which is held together by a few miles of nylon thread. Marine wildlife is attracted to the shade provided by FADs.     

Abandoned FADs are illegal. They can cause a wide range of adverse environmental impacts, including the entanglement of marine life (particularly sharks and turtles), act as a habitat for the spread of invasive species, and wash ashore on beaches or become stranded on coral reefs. Many lost or abandoned FADs sink, causing environmental harm to deep-sea habitats.

The material the FADs are made of matters too. FADs are required by Italian law to be biodegradable. All the FADs removed by the Sea Shepherds from the South Tyrrhenian Sea are illegal and made of plastic, says Nicola Silvestri, frigate captain and head of the Fishing Control Centre area in Western Sicily. They also lack markings which allow them to be traced back to the fishing boat that used them, he says.

"Illegal FADs are very cheap to produce, but at the same time highly dangerous for ecosystems," says Andrea Morello, president of Sea Shepherd Italy. "These devices are installed by fishers in the month of August, then they catch fish around them in summer. Eventually, winter storms remove the devices, creating tonnes of hazardous and plastic waste floating in the sea."

In this stretch of sea around Sicily's Aeolian Archipelago, the target fishing species in the summer are juvenile ricciola, bluefin tuna, juvenile swordfish and pilot fish. FADs can damage the entire population, by preventing juveniles from maturing and reproducing.

The Sea Shepherd mission is part of the organisation's ongoing Siso operation in Sicily to combat these illegal fishing devices.

"We are witnessing the biggest marine environmental disaster ever," says Morello. "The sea is like a minefield full of FAD lines in every direction, placed by fishers who split the sea surface among them, threatening biodiversity."

The Sea Shepherd volunteers remove the long nylon threads attached to the FADs which can harm fish, turtles, humpback whales and dolphins by trapping and suffocating them. According to Sea Shepherd, there are more than 36,000 FADs, each one composed of almost 1.2 km (0.7 miles) of nylon lines in the South Tyrrhenian Sea, part of the Mediterranean Sea.

It takes the volunteers one hour to extract almost 2km (1.2 miles) of a FAD line, it's the first out of seven removed that day. Not far away, a police coast guard boat is monitoring the work: later it will seize the illegal plastic materials. The use of FADs made from plastic waste, without GPS trackers, is an environmental crime in Italy.

Sarah, a young German volunteer, rings the bell installed on the deck of the vessel, to celebrate and notify the crew that another FAD has successfully been extracted from the seabed. In total, the volunteers haul seven FADs onto the deck that day – their combined mass is the same size as a small car.

Sea Shepherd runs covert missions, so that they are undetected by illegal fishers. The organisation maps the FADs using deep-sea radar technology and binoculars and removes them in collaboration with national maritime authorities.

Between 2017 and 2024, the organisation removed 676 FADs from the Mediterranean Sea, says Morello. "We define ourselves as FAD hunters: here to protect the sea. We are also carrying out the first census of FADs ever realised in the Mediterranean Sea," he says.

The data collected during this mission will be analysed as part of a research project that Sea Shepherd runs with the National Biodiversity Future Centre of the University of Palermo in Sicily and the Cima Research Foundation, based in Liguria, Italy. Using statistical analysis, Sea Shepherd has been producing maps since 2017 to identify for the first time the extent of this ghost labyrinth created by FADs anchored to the seabed.

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"With the information provided by Sea Shepherd, we were able to have a precise mapping of the location and composition of these devices," says Alberto Sechi, a marine biologist at Cima Foundation. "Since 2017, the plastic lines (mostly polypropylene) used to anchor the FADs exceeds 2,500km (1,553 miles): that corresponds to the distance between Paris and Moscow."

In a single night, Morello says the Sea Shepherds discovered around 912 FADs in the waters surrounding the Sicilian island of Alicudi, each one composed of more than 1km (0.6 miles) of nylon threads. "Multiplying the number of FADs we found by the medium length of each thread, the total length of lines used in this area is a staggering 43,200 km (26.284 miles) of nylon: this is more than the circumference of the entire planet Earth," says Morello.

Sea Shepherd's work involves removing as many FADs as possible, but then, the disposal problem arises. In 2022, the non-profit started collaborating with iMilani, an Italian company that specialises in building plastic crates from recycled materials. Together, they have created the Sea Turtle Crates project, which aims to transform the FADs into plastic crates for sea turtle rescue operations. After the entangled turtles have been freed from the FADs, they are put into the crates which Sea Shepherd uses to transport them to veterinarians. Six loggerhead turtles have been rescued to date and 100 turtle recovery boxes have been created from FADs, says Roberto Milani, founder of iMilani and a freediver.

The company is hoping to design other items with FADs waste in future, including pens and other gadgets, which can be sold to finance Sea Shepherd's activities, says Milani.

On the bow of the Sea Eagle vessel, the boxes for injured turtles are piled to the side of big bags full of plastic lines extracted from the FADs. In one day at sea, the crew removed seven FADs composed of 6.5km (4 miles) of nylon lines and plastic containers. Their labels reveal their previous lives: from hospital waste and corrosive liquids, to oil, gas and detergent jerrycans. Using radar, the Sea Shepherds map more than 100 FADs throughout the day.

The crew's work begins early in the morning, and continues until sunset, with brief breaks for meals. Tuti, 23, an Israeli volunteer, prepares a vegan buffet each day. Today's menu is inspired by Latin American foods, such as empanadas, chimichurri, black beans mole and corn tortillas, which Tuti learned to cook during a Sea Shepherd mission in the Gulf of California, where she worked to protect the last vaquita dolphins.

Onboard are 20 volunteers, from four continents with different ages and backgrounds: from Willie, a 20-year-old German student, to retired engineer and sea captain Gigi, 63, who joins Sea Shepherd's missions several times a year.

"We are here because we want to be part of the solution. We are sort of part of it, by removing all those plastics from the seas," says Zafar from Pakistan, who is in charge of measuring and cataloguing each FAD for the database. "I don't understand people's insensitivity towards the sea and its inhabitants," he says.

Many FADs are anchored to the seafloor with stones or buckets full of cement, says Teresa Romeo, director of the Sicily Marine Centre at the Anton Dohrn Zoological Station in Naples, Italy. She has been studying FADs since the 1990s. "They modify the seabed environment and affect all the species living there," she says.

Romeo says a mandatory recovery of all FADs should be implemented. "We need to establish a spatial management plan to define a specific area [for FADs] and replace floating materials with biodegradable ones, in order to have a more sustainable fishing practice in the Mediterranean Sea," says Romeo.

Sea Shepherd makes "a great contribution to the mapping actions of FADs and their efforts are useful for monitoring impacts, but in my opinion the aim cannot be drastic removal, but to regulate their use," she says.

But creating biodegradable devices from materials such as hemp is difficult due to the high cost, according to Sechi. "Creating a completely biodegradable FAD is a significant challenge, and so far, no one has come up with a solution," he says. "One alternative could be hemp, but kilometres of hemp thread are very expensive, and no angler would spend that much."     

Experts such as Romeo say that the transition to biodegradable and non-toxic materials would be an important part of the solution to reduce marine pollution from fisheries based on FADs. As well as breaking down in the ocean, biodegradable materials may contain fewer toxins and heavy metals, compared to plastic, says Romeo, though she agrees that cost is a major barrier for materials such as hemp.

In the meantime, the Sea Shepherds continue to sail the seas to map and remove illegal fish-trapping devices, collaborating closely with the local coastguard, researchers and private enterprises to crack down on this environmental crime. 

"This alliance is a solution to protect the deep sea," says Morello.

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