The photo is genuine. It was taken from an article titled Shark Detectives in the September 2005 issue of Africa Geographic magazine and was taken by a group of researchers studying great white sharks off the coast of South Africa.
From the Shark Detectives article:
Sitting in a 3.8 metre sea kayak and watching a four-metre great white approach you is a fairly tense experience. Although we had extensively tested the shark’s reactions to an empty kayak and had observed no signs of aggression, this gave us little comfort as we eyed a great white heading straight for us, albeit slowly. Just a metre or so from the craft it veered off, circles and slowly approached from behind. It did this several times, occasionally lifting its head out of the water to get a better look. Then it lost interest, and as it continued on its way we were able to follow a short distance behind. Once we’d come to terms with having nothing between ourselves and a four-metre shark except a thin layer of plastic, our kayak made an ideal research platform for observing great white behavious in shallow water. Its advantages are twofold: it is inconspicuous and appears not to cause the sharks to alter their behaviour for long, and it allows us to watch them in a natural situation, as it is not necessary to attract them to us with food.
Read the full article here: http://www.whitesharktrust.org/pages/me ... dia25.html
http://www.whitesharktrust.org/pages/me ... dia26.html
This photo was taken from the same sequence of photographs and appeared in the December 2005 issue of The Big Issue magazine.