Militant conservationist Paul Watson, who is wanted by Interpol, has confirmed he is back onboard a Sea Shepherd vessel and ready to confront Japanese whalers.
The Canadian's whereabouts had been a mystery since July when he jumped bail in Germany, where he was arrested on charges stemming from a high-seas confrontation over shark finning in 2002.
Sea Shepherd had said the white-bearded captain would be involved in this season's campaign against Japan's whaling operations and he confirmed in a statement that he was back in charge.
"The deck of the Steve Irwin is again under my feet," Watson said late on Tuesday. "I have an awesome crew and our ship is on course for Antarctica."
Sea Shepherd, whose vessels harass the Japanese whaling fleet to prevent them slaughtering whales, had previously said its ships would journey north to head off the harpoonists before they reached Antarctica.
"Apparently they believed it," Watson said.
"Their coastguard mobilised and they went to a great deal of expense and effort to sneak quietly out of port.
"Of course we had no intention of heading north at all. We are waiting for them in the south, but before they reach the Southern Ocean Whale Sanctuary."
The Steve Irwin, Sea Shepherd's flagship, left its Melbourne dock on 5 November. It is not known where Watson boarded the vessel.
Watson said it had been a long, four-month journey from Germany.
"Across two oceans and countless rivers, over three mountain ranges, across a desert, over lakes, and through dozens of cities and towns," he said.
"A trifle inconvenient without a passport or any form of identification and all the more difficult without credit cards or access to ATM machines, without access to the internet or even a cellphone."
Watson said he travelled "primarily through the largest and most free nation in the world — The Ocean!".
"I can't go into details of my travels over the last four months. I may have to do it again sometime in the future," he added.
Watson, who for years has harassed Japan's whale hunt, was arrested in Germany in May for extradition to Costa Rica over the shark finning incident in 2002. He says the charges are politically motivated, driven by Tokyo.
Sea Shepherd's ninth campaign, named Operation Zero Tolerance, is its largest against Japan's whale hunt and involves four ships, a helicopter, three drones and more than 100 crew members.
Japan hunts whales using a loophole in a global moratorium that allows killing the sea mammals for what it calls "scientific research", although the meat is later sold openly in shops and restaurants.