A ship used to obstruct a Japanese whaling fleet arrived in Dunedin yesterday after spending nearly three months in the Antarctic.

The Sea Shepherd Conservation Society flagship Steve Irwin arrived at Birch St wharf about 10am.

The ship was used in direct action campaigns against whaling in the Southern Ocean.

Captain Wyanda Lublink said the 59m-long boat and its 36 crew members had been at sea for 83 days after leaving Melbourne on December 3.

The "boiling hot" weather in Dunedin and its "greenery" were  a stark contrast to the Antarctic.

"We’re enjoying the sun. We’ve got our T-shirts and shorts on and we are going to have a beer later. It’s good to be back."

The ship was in Dunedin to refuel and would sail on Monday towards Australia.

"We have done very well — 83 days without getting fuel is a record ...

"We spent a whole lot of time there trying to stop the killing of the whales," Capt Lublink said.

Sea Shepherd flagship Steve Irwin motors up Otago Harbour yesterday. Photo: Stephen Jaquiery.

A Japanese fleet killed 333 minke whales last season when the society did not have the funds to send its two boats — Steve Irwin and Ocean Warrior.

The 15-strong crew on  Ocean Warrior was completing a  campaign in the Southern Ocean as the whaling season was nearly finished.

Direct action by  the two boats this season made "a really big dent" in reducing the number of the whales killed.

The ships followed the good weather in the "massive" hunting ground, as killing whales was difficult in bad weather.

The action of the ships included getting in between the harpoon and the whales and blocking the stern of the Japanese whaling fleet ship Nisshin Maru, where the whales were dragged up.

Using a helicopter, they found  Nisshin Maru on January 15 and stopped whales being killed for more than 24 hours, she said.

The public can tour  the ship in Dunedin between 10am and 5pm tomorrow  and Sunday at Birch St wharf.

shawn.mcavinue@odt.co.nz