A British swimmer overcame the 25 km-long Cook Strait on April 22 as part of his bid to conquer the Oceans Seven. Adam Walker wanted to be the first British man to complete the group of seven long-distance swims around the world.
As he was crossing New Zealand's Cook Strait, he spotted a great white shark just below him. He was previously told that there was no need to worry about sharks in Cook Strait.
Just when he was about to panic, Mr Walker said a group of 10 dolphins had suddenly surrounded him and swam with him for more than an hour.
He said the dolphins swam close enough to him that he could just reach out and touch them. His marathon swim with the dolphins was caught on video as he was crossing New Zealand's waters for the Whale and Dolphin Conservation Charity.
Mr Walker said people watching the video will not see the great white shark. The pod of dolphins may just have saved his life as they swam with the British swimmer until the shark eventually swam away.
Mr Walker late on wrote on his Facebook page that he would like to think that the dolphins had protected him from the shark and "guided" him to safety. He said that part of his quest will stay with him forever.
Previous research has shown dolphins tend to protect humans from sea predators like sharks.
Mr Walker's final swim on the Oceans Seven will be held in August at the North Channel in Ireland. He posted images of his "guardian" dolphins on Facebook a day after his long-distance swim. He crossed Cook Strait in 8 hours and 36 minutes.
Aside from the potential danger of a shark attack, he had motion sickness and felt like he was swimming in a washing machine. He told media that he had tried to vomit as he swam but it didn't work out for him.
Mr Walker is nearing the end of his quest. He has made it across the English Channel, Strait of Gibraltar, Molokai Channel, Catalina Channel and Tsugaru Channel, according to reports.
WATCH the video of Adam Walker surrounded by a pod of dolphins here.