As they hauled up their cray pot they noticed what they thought was a dolphin caught in the line.
It wasn't until they reached shore and checked the photos they realised what they had actually caught.
"We sent the photos to DoC, who confirmed it was a great white." The pair estimated the shark to be about 2 metres in length.
The men have received calls from friends all over the world who have read their story.
They have since gone on to appear on TV One's Seven Sharp to tell their tale.
"There were a few cringeworthy moments," Mr Eivers said. "We weren't overly keen for the limelight but when they flew the crew from Auckland it was hard to say 'no'."
He said the incident still feels surreal. "We were pretty relaxed about the whole thing at the time but in hindsight I guess it could have ended worse."
Mr Eivers, a keen spearfisherman, said he might leave the speargun at home and stay on the boat in the next few weeks. "It's all well that ends well, the shark survived and we are still in one piece."