Ocean Ramsey, yes Ocean, is attracting worldwide attention for swimming with sharks as she tries to publicise the threats the fearsome creatures face.
Recently posted footage shows Ramsey holding on to the fin of a great white estimated to be around five metres long.
"It's sad to think that the human race could be responsible for the extinction of such vital and beautiful animals," she said on her website waterinspired.com.
"Sharks are being over fished and finned at unsustainable rates."
Great whites are thought to number only several thousand worldwide, with major populations found off Australia, South Africa, New Zealand, California and western Mexico, and in the Atlantic, Reuters reported recently.
Australia and South Africa had designated their great whites as endangered and the shark was listed as vulnerable worldwide by the International Union for Conservation of Nature.
The California Fish and Game Commission voted last month to recommend protection of the great white shark.
While the great white was among three shark species most associated with attacks on humans, along with bull sharks and tiger sharks, such encounters were exceedingly rare.
But great whites hold a special place in the popular imagination due mainly to their size, with some specimens known to have reached six metres in length and 2270kg in weight.
A new study estimated an astounding 100 million sharks are killed each year by commercial fishing, a rate 30 to 60 per cent higher than is sustainable. Sharks are fished for their fins in particular.
Last week Kiwi Adam Strange was killed in a shark attack while swimming at Muriwai Beach. He is thought to have been attacked first by a bronze whaler shark, and then by a great white.
Globally, shark attacks have increased every decade since 1900. Last year's 12 fatalities, three in Australia, was almost three times the average of 4.3 from 2001 to 2010, according to the International Shark Attack File.
Despite the widespread publicity given to shark attacks, Ramsey, who describes herself as a professional scuba instructor, surfer and advanced free diver said she felt so fortunate that some of the greatest moments of her life had been diving with great white sharks.
"It's difficult to express the incredible joy and breathtaking emotion experienced locking eyes with a great white shark. Watching the shark acknowledge and observe me, while I peacefully and calmly allowed it to swim towards me, and then experiencing it accepting my touch, allowing me to dorsal and tail ride," Ramsey said.
"A lot can be said between two creatures that don't speak the same language."
But while Ramsey described the encounter in rapturous terms she also warned: "I'm not advising that people go out and just jump in to the water with great whites, just as I wouldn't recommend jumping into a yard with a strange dog. Sharks do need to be respected as wild animals and appreciated for their role as top predators in the ocean ecosystem."