SEA Shepherd leader Paul Watson thought the 2010/11 anti-whaling campaign in the Southern Ocean would be the last.
Following weeks of harassment by the Sea Shepherd fleet, Japanese whalers called off their cull early and left with a fraction of their annual quota.
"Last year we drove them out," Mr Watson said.
"I thought that was the end of that."
But Japan is not backing down that easily.
Mr Watson said the Japanese whaling fleet would return to Antarctic waters this year, with $27 million worth of enhanced security.
He said their motivation had now shifted from hunting whales to refusing to surrender to Sea Shepherd Conservation Society.
Not one to step away from a fight, the controversial activist is now preparing to embark on a three-month campaign in the Southern Ocean, where he and his 88 volunteer crew will again directly intervene in the Japanese whaling fleet's annual cull.
Three ships, the Steve Irwin, Brigitte Bardot and Bob Parker will leave Australia for Antarctic waters in early December.
With Sea Shepherd's previous tactics including ship ramming and boarding of whaling vessels while at sea, Mr Watson is entering this year's campaign with his trademark fearless approach.
He said he and his crew were prepared to die for the cause.
"They will have to kill us to prevent us from intervening once again," he said.
Mr Watson is currently in Australia to promote the campaign and will visit Byron Bay this Saturday to meet and greet supporters.
The conservation group has strong ties with the Byron Bay area and last year Ocean Shores man Howie Cook was among the Sea Shepherd crew.
The visit is timed to coincide with Byron's annual Sea Shepherd fundraiser at the Great Northern Hotel tomorrow night, featuring performances from Ash Grunwald and Kram's band, Krash; Andrew Stockdale from Wolfmother, Dallas Frasca and the Grains.
Mr Watson will give a presentation at the Owl and the Pussycat, Byron Bay on Saturday night.