KNEELING ON A YELLOW BAR waist-deep in water, I wait in the cold Atlantic. The cage rattles and jolts as the boat lurches on anchor. Pulses of adrenalin override thoughts of the chilly 9º water temperature.
Above me, an eager crowd jostles for position, looking into the water in anticipation. Were here to encounter a revered predator, the great white shark.
As the excitement level amplifies, the skipper yells: Down diver, down!
I take a breath and plunge to the bottom of the cage. As the bubbles clear, an instantly recognisable shape materialises, barely appearing to propel itself, gliding effortlessly.
Gansbaai is renowned for big sharks, which are sustaining a thriving cage-diving industry. This year alone, 26 cage-diving permit applications were received by South Africas Department of Environmental Affairs, including 14 from new applicants.
But, not everyone supports the industry, and questions are being raised about this form of tourism. Of special concern is the potential modification of the animals behaviour to associate humans with food, resulting in an increased risk of shark attack.

AMONG A COMMUNITY DIVIDED, I make my way along Highway 2 from Cape Town towards Gansbaai. I am meeting Mike Rutzen, internationally regarded as the Shark Man from his freediving white shark documentaries, to see what the debate is about.
I stand with Mike in the early morning light overlooking Kleinbaai harbour, just south of Gansbaai. We drink strong coffee as he shows me around the spacious foyer of the Shark Diving Unlimited (SDU) office. Images from some of the most accomplished marine image and film-makers from around the globe adorn the walls, gifts from the close encounters Mike and his team have set in motion.
One image catches my attention, a picture of Mike swimming uncaged, with an approaching white shark.
According to Mike, and contrary to common perception, the white shark has a gentler side to its nature. If these sharks targeted people as food, wed be in big trouble. Fortunately, we taste more like bony chicken compared to a Cape fur seal, he tells me, with a passion born of first-hand experience.

WHY THE CAGE-FREE DIVING Its partly to learn about these amazing animals and partly about education - to show the world that they are not the ruthless killers the media portrays them to be. The image resonates for the duration of my stay as I contemplate the contrasting view.
For or against, white shark tourism is here to stay in South Africa. Operators have worked here since legislation was passed to protect the species in 1991.
The common denominator that creates these white shark meccas such as Gansbaii and False Bay is the key ingredient that makes them a haunt for the sharks - Cape fur seals, their favourite meal.
The seals entice the sharks, just as the picture-postcard scenes of Cape Town attract the tourists.
On a desolate outcrop named Geyser Rock, about five miles off Gansbaai, 60,000 Cape fur seals nervously overlook nearby Dyer Island.
The sharks wait in a narrow stretch of water between the two islands for tired seals to return to their rocky home. This is Shark Alley. The sound of hawking gulls and barking seals echoes across the windswept sea, and kelp fronds flow in the shallows, providing refuge for animated seal pups.
In the distance, boats fishing for pilchard and anchovy chug past Southern right whales on an annual pilgrimage from Antarctic waters.
The area is steeped in local history and mementos of mankinds interactions with the marine environment.
Not all such interactions are welcome however, including a spate of shark attacks off Cape Town in recent years.
The latest occurred on 12 January at a popular swimming beach called Fishoek. Fuelled by the media, the attacks caused some to blame the shark cage-diving industry.
Thumbing through my travel guide to southern Africa, I stumble across such a view: Operators use bait to attract sharks to the cage, which means that these killer fish are being trained to associate humans with food.
The broken perspective seems to comes down to one thing: conditioning. Websters Revised Unabridged Dictionary defines this as a learning process in which an organisms behaviour becomes dependent on the occurrence of a stimulus in its environment.
Have the sharks changed their behaviour in response to cage-diving Licensed operators in South Africa must adhere to strict permit regulations to minimise their impact on the sharks. They are not permitted to intentionally feed them, and must limit the provision of food rewards.
If great whites are being conditioned, the same sharks could be expected to show the same predictable behaviour each day. With this in mind, I board an early-morning boat for Geyser Rock.
As the anchor drops, I expect to see sharks already under the boat, awaiting a routine meal. But it takes 90 minutes of chumming (using fish mash to draw the shark to the boat) before a dark shape materialises off the stern.
According to Mike Rutzen, each day is different on the water with the sharks. Sometimes it takes 20 minutes for a shark to turn up; sometimes no sharks are seen at all. When they do turn up, they may stay for a brief moment, or the entire time that were there.
I look across at the islands, and smell the scent of thousands of seals floating on the wind. We are not attracting the sharks to this location; the seals have already brought them here, says Mike. They do not depend on us for anything, they are curious, and free to come and go as they please.
The deckhand, knee-deep in a bucket of fish, works his foot up and down to create a pungent sashimi slick. The broth is poured into the sea from a wooden platform on the stern.
Gulls shriek in delight as they capture small edible pieces among the offal.
We want to draw the sharks to the boat by setting up an environment that mimics that of a shark kill, says Mike. Releasing the oil and juice into the water sets up an odour corridor for the sharks. They swim up to the boat from downcurrent, drawn by the smell of the burley.
A shark swims cautiously around the burley trail, investigating the surroundings. It is enormous, almost 5m long, its streamlined design making it look more like a submarine than a living animal.
After several minutes it seems satisfied and starts to investigate the tuna head on the line - the visual cue.
It is cautious at first, turning away
at the last moment, testing the fast-moving target. Eventually, the shark shows intent and snaps at the bait, but timing is everything and Mike flicks the bait away to ensure that it isnt taken.
On another pass, after perusing the bait, the shark bites the cage. The sharks have a sixth sense, known as the Ampoules de Lorenzi, making the signal emitted by metal in water similar to that of a struggling fish, Mike tells me. From the sharks perspective, it can smell the fish, but observes the cage and boat as a single entity.
The sharks are not trying to attack the divers in the cage; they are just confused by the signals that they are detecting.
Karl Laroche of Simon Fraser University in British Columbia has recently investigated the impact of cage-diving on sharks. His research team tested whether a change in natural feeding behaviour existed when chumming was taking place.
Their study site was Seal Island in False Bay, which offers a rare opportunity to observe white sharks natural hunting behaviour. The size of the seal pups, combined with the topography of the seabed, means that the sharks regularly breach the surface in spectacular ambush attack.
The study found that although the use of burley had a small effect on the behaviour of some sharks, most showed no interest in the food reward on offer. More importantly, those sharks that were interested in the bait showed a decreasing response with time.
Researchers Ryan Johnson (South African Marine Predator Lab) and Alison Kock (Save Our Seas Shark Centre) measured the amount of time that sharks spent at cage-diving boats to determine whether a behavioural change was present. At both False Bay and Gansbaai, individual sharks spent progressively less time at the boat with increasing experience.
This result was later confirmed through the use of acoustic tags, when two sharks from False Bay ceased visiting the chumming vessel altogether over consecutive days, despite being detected in the near vicinity.
While at Mossel Bay, white sharks near the sole chumming vessel failed to be visually detected 49% of the time, revealing a clear ability of the sharks to ignore chumming activities.
The results of this research contradict what would be expected if conditioning was occurring, so it seems that while baits and chum may be used to attract sharks, they do not appear to be making the shark dependent on the operators for food.

THE SHARK CAGE-DIVING INDUSTRY also offers conservation and educational benefits to the white sharks.
The presence of and human interest in a threatened species off Dyer Island and Geyser Rock has led to the designation of a marine protected area. The white sharks in this instance are flagship species that offer a substantial protective benefit that flows onto all marine organisms, large and small, that occur within these waters.
The presence of cage-diving operators also ensures effective surveillance for illegal fishing activities in their locales. And several research programmes are being developed to improve our understanding of the white shark.
I watch one afternoon as a team of researchers from the Department of Environmental Affairs (DEA) board the Sharks Diving Unlimited vessel for DNA sample collection.
I later spoke to Mike Meyer of the DEA. Without the logistical assistance provided by companies such as SDU,
it would be very difficult for us to fund many of our projects, he said. Their knowledge of the area is also of great benefit when we are trying to complete our work in tight time-frames.
Mike Rutzen and his team also service an arrangement of acoustic listening stations for the DEA. These are fastened to the seabed around Geyser Rock and Dyer Island, and contribute important insights into
the movements of the sharks.
Many questions about great whites remain unanswered. Determining their numbers and movements is Sara Andreottis aspiration. She is helping to build a white shark database, and spends a significant amount of the year on site with SDU to identify individuals.
To do this, Sara photographs the dorsal fin and records distinguishing characteristics, such as scarring, colour patterns and notches. Sara has travelled from Italy to study Gansbaais great whites, and hopes to extend her project into a PhD. I am living my dream over here, collecting data on these amazing creatures, she tells me.
Late one afternoon, sitting in the SDU lounge area, Sara yells: Yes, we made it, thats 100 sharks! She tells me she has been in Gansbaai identifying sharks since April. Its now mid-June, and
I remember the sign I had seen when
I arrived at the Tourism Associations Great White Adventure Centre: Welcome to Gansbaai, the Great White Shark Capital of the World.
If this is the great white capital, and only 100 individuals have been identified in a three-month period, alarm bells are sounding about the future for this species.
Recent data indicates a gradual global decline in abundance and size of great white sharks. The International Union for Conservation of Nature (IUCN)s first assessment of open-ocean sharks and rays identifies that almost a third of these species (including the white shark) are at risk of extinction.
Although protected, they continue to be captured by long lines, drum lines, set lines and bather-protection devices such as the shark nets off the Kwa-Zulu Natal coast. Additionally, white sharks are protected under the Convention of International Trade of Endangered Species and domestic South African legislation, though this seems to be failing in its conservatory premise.
A thriving black-market trade in great white shark products persists, with the illegal sale of fins, jaws and teeth from South African sharks. Jaws can fetch up to US $50,000, while a single tooth can sell for $600.

A NEW PERMIT SCHEME was brought in this June in a bid to tighten up on cage-diving. Of the 26 applications, 14 from new applicants, the Department of Environmental Affairs allocated 15 permits, eight in Gansbaii, three False Bay, two Mossel Bay and two Quoin Rock, a new location.
Some existing permit-holders were rejected because they were unable to demonstrate adequate use of their permit, access to a properly qualified tour guide; adequate insurance coverage or that they had a valid tax clearance certificate. But no permits will be issued until an appeals process has been completed.
Compliance of the shark-diving industry is not of high priority, due to an illegal trade in abalone that takes up the bulk of compliance resources, Mike Meyer of the DEA told me. The DEA relies on the industry managing itself, with operators informing on others who break permit conditions.
One operator was recently forced to remove stabilisers that were injuring sharks, and another in False Bay had its licence revoked after it broke the rules.

MIKE RUTZEN SAYS he doesnt expect to bring together the divided perspective on white sharks, but tries to make a difference, one person at a time.
On my final trip to sea, I see this in action as another fresh-faced boatload of perceptions change. Divers and spectators start the day with mixed emotions, finish it with a smile, and leave with a new-found respect.
In a world where shark populations are under much greater threat from humans than the contrary, the impact
of the white shark tourism industry off South Africa seems insubstantial.
This industry affords conservational and educational benefits that may just open enough eyes to make a difference. Education comes in no greater form then the bulky frame of a great white slicing effortlessly through the water.

Shark Diving Unlimited, www.sharkdivingunlimited.com