A whale surprised a group of scientists when it suddenly emerged next to their boats and began to try to "play" with them in Tasmania last week.
Deckhand Tony Summers told ninemsn the boats' crew was initially worried the whale might flip their dinghies but it seemed to know they were there.
"The dinghies were quite close and so when it actually turned to go under the other boat ... the tail was so close to being under our dinghy that we could have been flipped but it never touched either of us," Mr Summers said.
"It seemed to be playing with the dinghies, swimming around and under us."
Mr Summers said the whale looked about 12 metres long and some crew thought it might be a southern right whale.
"Everyone was just in awe," he said.
"For something to come that close, that will never happen again in a lifetime."
The crew were in Wineglass Bay, near Freycinet, to carry out scientific research into sea urchins and had not expected to see whales at this time of year.
The southern right whale is one of three whales listed as endangered in Tasmania's Threatened Species Protection Act 1995.