Sea Shepherd returns to Southern Ocean

Anti-whaling group Sea Shepherd says it will unleash its biggest, most aggressive campaign yet against the Japanese whaling fleet in the Southern Ocean this summer.

Sea Shepherd will send four ships and 120 crew on the mission with one of the ships, Bob Barker, leaving Sydney on Saturday, the ABC reports.

Speaking in Hobart, the vessel's captain Peter Hammarstedt said a new ship would also be used in the fight but its identity and location were being kept under wraps.

He said drones would be used for the first time to locate the fleet.

"It's the same kind of UAV (unmanned aerial vehicle) technology that's used by military organisations across the world with their reconnaissance efforts," he said.

"So what the UAVs will do is allow us to find the Japanese whaling fleet earlier than ever before, we'll be able to find them undetected...thereby shutting them down earlier than ever before".

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