The two men and two women completed their voyage in a specially-built boat in 31 days.

One of the rowers, Steven Gates, told reporters the four had battled severe weather, encountered sharks and whales, and narrowly avoided colliding with merchant ships.

"We had some really lucky incidents during the night when ships didn't see us," he said. "If one of us hadn't grabbed the spotlight and shone it in their eyes, we probably wouldn't be here."

The Australian newspaper, meanwhile, reported two other Australian men are struggling to be the first to complete a voyage from Australia to New Zealand in a kayak.