A British man will plunge into sub-zero waters in the Antarctic on Tuesday to campaign for the creation of three huge marine parks to stop overfishing.

Lewis Pugh is credited with playing an important role in the agreement earlier this year to create the world’s largest marine protected area (MPA) and make fishing off limits in much of the Ross Sea, a bay in the Southern Ocean.

The endurance swimmer last year took to the region’s freezing waters to fly the flag for the MPA, and met and lobbied the Russian government, which had previously blocked the plan. He calls this mix of extreme swimming and hobnobbing with officials “Speedo diplomacy”.

“The main significance is the precedent it sets,” Pugh said of the Ross Sea marine park, which was agreed by 24 nations and the EU in October.

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Now he wants to create three more similar sanctuaries for marine life – in East Antarctica, the Weddell Sea and Antarctic peninsula – which together with the Ross Sea MPA would collectively cover around 7m sq km, an area around the size of Australia. As part of his campaigning, he plans to swim on Tuesday for 5km in -1C waters in the Bellingshausen Sea, which is along the west side of the Antarctic peninsula.

That will be followed by a 3km swim in the “whale graveyard” around South Georgia, the British Overseas Territory where British sailors killed more than a million whales in the late 19th and early 20th century.

Bad weather and the freezing water will be the main challenges for Pugh, who has previously swum across the north pole and in Himalayan glacial lakes. When scientists studied him, they found his core temperature naturally rises by nearly 2C ahead of a swim, to cope with the cold.

The 47-year-old has already undertaken one “warm-up” swim for his current expedition, around Cape Horn in relatively balmy 7C waters. But after a first swim there he came up short at 850 metres and he had to redo the entire thing, swimming another 1km. He said the nutrients in the water there meant it was “bubbling with life” and he was watched by barking leopard seals.

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Conservationists think that the East Antarctic MPA is likely to be the next one to be agreed by nations when they meet under the aegis of the CCAMLR treaty set up to protect Antarctic marine life.



“We hope to see the East Antarctic MPA go through in 2017. We think it’s realistic, that’s been on the table as long as the Ross Sea,” said Andrea Kavanagh, director of Southern Ocean Sanctuaries at Pew Charitable Trusts.

Pugh thinks the creation of four marine parks in Antarctica would be hugely valuable to science. “I think it’s very, very significant. How can we understand to properly protect ecosystems if we don’t even know what a healthy one looks like?”