The discovery began on June 6th, when Sea Shepherd's vessel Sea Eagle received a report from the Guardia di Finanza's Operational Aeronaval Unit – the maritime branch of Italy's financial police, which patrols Italian waters for trafficking and customs violations – of an illegal driftnet sighting. The crew arrived to discover two dead Mobula mobular, giant devil rays that can grow to more than three metres across, strangled by the driftnet with 45-centimetre mesh, a type of gear banned across the Mediterranean since 2002. A day earlier, in the same waters, the crew had pulled in a separate abandoned net containing three dead dolphins, including a 90-centimetre newborn calf.

A Coordinated Response

The mesh, floats, and buoys matched what crews had found in the net that killed the two rays, a sign that this was no isolated net but a far larger illegal system. Recognising the scale of what was at stake, the Guardia di Finanza's Operational Aeronaval Unit, the Italian Coast Guard, and Sea Shepherd's vessels Sea Eagle and Spitfire launched three days of continuous, round-the-clock patrols along the Calabrian coast to track it down.

By the time the operation wrapped, the joint patrol had pulled 19 kilometres of driftnets with 45-centimetre mesh out of the water and freed four Mobula mobular devil rays, an ocean sunfish (Mola mola), and a loggerhead sea turtle (Caretta caretta), all of them alive. 

Why the Tyrrhenian Sea, Why Now

Operation SISO patrols the southern Tyrrhenian Sea, the stretch of Mediterranean off Italy's west coast between Sicily, Calabria, and the mainland, through the Atlantic Bluefin Tuna's spawning season each June and July. The species suffered an 80% collapse in spawning biomass between the 1970s and 2010s, and while international recovery plans have allowed numbers to rebound, crews are once again sighting tuna over 250 kilos in these waters, a single illegal longline set during spawning season can undo years of that progress in one night.

Driftnets, longlines, and abandoned FADs (Fish Aggregating Devices, floating structures used to lure fish that are often left adrift after use) don't only threaten tuna. They indiscriminately catch sharks, turtles, dolphins, and rays, and contribute heavily to plastic pollution in Italian waters: Sea Shepherd estimates more than 1,500 FADs are illegally anchored in the region every year.

Nine Years of Operation SISO

This year marks the campaign's ninth consecutive season. Operation SISO is named for a young sperm whale found dead in the Aeolian Islands in 2017 after becoming entangled in an illegal driftnet; his skeleton is now displayed at the MuMa museum in Milazzo, not far from where this year's operation took place, as a reminder of what's at stake. Since the campaign began in 2018, Sea Shepherd Italia has worked alongside the Coast Guard and Guardia di Finanza to remove illegal gear from the Tyrrhenian Sea, a partnership the organisation credits with a 70% drop in illegal fishing activity in the area since 2022.

The Season So Far

Beyond this week's operation, Operation SISO9 has already logged a wider set of results since launch, as crews continue daily patrols of the coastline:

* 15 km of illegal longlines, carrying close to 400 hooks, seized by Spitfire
* One illegal 100-hook longline targeting Bluefin Tuna found with a dead 270-kg adult still on the line
* 4 heavily polluting FADs removed by Sea Eagle
* Additional kilometres of abandoned driftnet, recovered and safely disposed

Sea Eagle and Spitfire will remain on patrol in the southern Tyrrhenian Sea through the Bluefin Tuna spawning season, working in direct coordination with Italian authorities to locate and remove illegal fishing gear before it can cause further harm.