Sea Shepherd’s hunting of poaching vessels in the remote Southern Ocean is not as well known as its efforts to stop Japanese whale hunters, but for one species it’s a lifesaver.

The deep-sea-dwelling Patagonian toothfish that inhabits the region has been a lucrative target for illegal fishing. Six vessels, which Sea Shepherd has dubbed the Bandit 6, have been raking in big bucks skirting international fishing regulations. The ships are capable of catching more than $1 million worth of toothfish—popularly known as Chilean sea bass—before returning to port.

The boats have operated mostly unencumbered in the remote expanse of the Southern Ocean, often avoiding capture by flying under “flags of convenience” that hide the vessel’s ownership and make prosecution difficult. The Commission for the Conservation of Antarctic Marine Living Resources has put the ships on its blacklist.

“What made them stand out was their brazen return to Antarctica, year after year, in spite of being repeatedly spotted by customs vessels and other legal operators,” Sid Chakravarty, captain of the Sea Shepherd vessel Steve Irwin, said. “We realized that the vessels were deliberately exploiting the loopholes in international law and acting with a purpose, fully aware of the immunity they enjoyed.”

But thanks in part to Sea Shepherd’s two-year-long “Operation Icefish” campaign, only one vessel of the Bandit 6 is still in operation. Officials in Senegal on Tuesday detained the Kunlun, a toothfish-poaching vessel Sea Shepherd has been pursuing for more than a year.

In February 2015, Chakravarty, who was then captain of the Sea Shepherd’s vessel San Simon, chased the Kunlun for eight days out of Australian fishing waters. The boat was fishing with illegal gill nets that drag along the seabed, capturing and killing fish indiscriminately.

“It is incredibly satisfying to know that the Kunlun, which was chased out of the Southern Ocean by my vessel in February 2015, has been unable to resume its illegal fishing operations,” Chakravarty said. “The work done by Sea Shepherd completes and at times fills the gaps in the work of governments, which are restricted by outdated legal conventions.”

The capture of the Kunlun leaves the poaching vessel the Viking as the lone bandit on the high seas.

According to Sea Shepherd, the Viking is suspected to be fishing in Antarctica, once again using banned gill nets in the region. Chakravarty and the crew of the Steve Irwin are searching for the Viking.

“Once the vessel is located, the role of the [Sea Shepherd] is twofold,” Chakravarty said. “One, to afford immediate protection to marine wildlife by blockading the illegal operations of the Viking and two, to embark on a pursuit of the vessel and work with international law enforcement agencies to ensure the vessel is detained upon arrival in port. Using the evidence collected, Sea Shepherd’s aim is to aid and assist ongoing investigations with regards to the Viking.”

That plan worked in 2014, when Sea Shepherd Capt. Peter Hammarstedt and the crew aboard the 788-ton Bob Barker embarked on a 110-day, 10,000-nautical-mile ocean pursuit of the Nigerian-flagged boat Thunder, which was illegally fishing in the Southern Ocean.

The Thunder, considered the most notorious poaching vessel among the Bandit 6, ended up sinking at sea, with the crew and captain rescued by Sea Shepherd. In October 2015, the Thunder’s captain and two senior crew members were found guilty of multiple charges of illegal fishing, given 32 to 36 months of jail time and fined more than $17 million by a court in São Tomé and Príncipe—an island nation that lies off the west coast of Africa in the Gulf of Guinea.

“The aim of this mission is to locate [the Viking] and replicate the successes of the previous missions and to deliver a final blow to the illicit toothfish trade,” Chakravarty said.

Source: www.ecowatch.com