Some scientists had to place themselves in precarious positions and, understatement alert, said things got a "little bit tense" in order to capture the amazing photograph seen here.
Shark biologist Michael Scholl and wildlife photographer/marine biologist Thomas Peschak were working together off the coast of South Africa when this opportunity presented itself.
The two had discovered large numbers of great white sharks gathering very close to some South African beaches. They wanted to get up close to discover what was bringing the enormous sharks close to shore, but their motor boat disrupted the research. The engine's electrical fields either attracted or repelled the sharks, making it impossible to observe the animals' natural behavior.
Scholl and Peschak turned to sea kayaks as a quiet and unobtrusive method of observing the sharks. They say the first attempts were a "little nerve-wracking" and that watching a 14 foot great white approach their 12 foot kayak made them "a little tense."
But these scientists knew great whites are not as aggressive and unpredictable as their reputation suggests, describing the animals as more cautious and inquisitive. After a few tests with the kayak, they were ready to begin their observations in earnest.
One day, a research partner, marine biologist Trey Snow, set out in the kayak. Peschak stayed aboard a research vessel called Lamnidea. Peschak tied himself to the boat's tower and, camera in hand, stretched out as far over the ocean as possible just waiting for a shark to come along.
Peschak says the shark pictured here caught site of the kayak and quickly dove to the seabed and inspected it from below. As it ascended and its dorsal fin broke the surface. Peschak says he hesitated a moment before snapping the shutter and was rewarded with a shot of Snow turning around to look behind him at the approaching behemoth.
Peschak took many other pictures during that day's outing but says none match this one in raw power.
During the course of their research, Peschak, Scholl and their team concluded the great whites come inshore in large numbers to interact socially, perhaps even to mate or give birth. The team watched many sharks interacting with one another at close range, following closely behind or swimming in tight circles around one another for extended periods of time.
You can learn more by going to www.thomaspeschak.com. A more detailed account is available in the book "South Africa's Great White Shark," by Peschak and Scholl.