The Great White Shark. The man-eating shark. Jaws. Who wouldn’t jump at the chance to see these big guys up close and personal?!?
Great white sharks are found in coastal waters in all of the world’s major oceans. Unlike many other sharks, they spend much of their time close to the surface of the water looking for prey. Their favorite meals are seals, sea lions, and often, other shark species.
The perception of the great white as a maneater started with Peter Benchley’s book Jaws (which Steven Spielberg made into a classic film!). Benchley later said that he regretted portraying the great white as a "killing machine" due to the effect it had on people’s fear of these creatures.
Great whites will sometimes bite something unknown in an attempt to identify it. Usually, after this “test bite” on a human, they swim away uninterested. Humans are not a favorite meal of the great white – we are too bony and don’t have the fat and protein of a seal or sea lion. For this reason, over 70% of victims of an attack by a great white survive -- the shark realizes that the person isn't a seal and moves on.
One of the densest populations of great whites is consistently found around Dyer Island, South Africa (just a few hours from Cape Town). I had to take the opportunity to see them for myself.
Critics of shark cage diving say that the sharks get used to being fed and will associate boats with food. They also say that being so close to humans in the cages will make them more accustomed to having people in their environment, especially in proximity to food. However, the tour groups don’t feed the sharks. They use chum, a mixture of fish parts and blood, which attracts sharks due to their keen sense of smell.
However, when the sharks arrive, they don’t find food, and often move on after just a few passes by the boat. Therefore, they don’t associate chum (or the boat) with a meal. Tour operators also sometimes use parts of fish as bait for the sharks – something to move through the water to attract the shark’s attention.
However, since fish isn’t part of the diet of great white sharks, again, they aren’t finding food when they follow the movement. And, I have to add that all shark tour operators are strictly controlled by South African conservation laws.
Finally, the dollars generated by the tourist industry helps to conserve the shark population. A great white jaw can fetch up to $30,000 on the black market. However, this is a fraction of the value live sharks can bring via tourist dollars. In Gansbaai, South Africa (where we were diving) a single shark can bring in $13,000-$30,000 each day thanks to tourists on boats.
During our few hours in the bay, we saw three sharks. Two were just over 6 feet and the third was closer to 11 feet!
Adult great white sharks average 13-17 feet long and weigh between 1500 and 2400 pounds. However, great whites have been recorded at 21 feet weighing over 7000 pounds! Ours were smaller because mature adults aren’t as curious (they tend to avoid boats) and already know that the smell of chum won’t lead them to a tasty meal.
Once the sharks came near the boat, they weren’t that easy to spot. The water is perfectly blue and all you can see is a vague shadow which slowly takes form.
The huge form of the great white is visible for just a few seconds and then they retreat to the depths again.
Great whites are one of the few shark species that lifts their eyes above the water to check out their surroundings. This photo was taken from inside the cage – no zoom!
Some of the sharks came quite close to the cage:
But getting a photo of them underwater wasn’t easy – they’re incredibly fast!
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| Look at the lower right corner – you’ll see the shark’s tail fin rapidly disappearing. |
Great white sharks often hunt from below. They are known to breach the surface of the ocean during high-speed attacks on seals and other unsuspecting animals. They can reach speeds of up to 40mph and launch themselves 10 feet in the air when coming from lower depths! Here’s a really poor photo of a great white breaching:
Seeing these huge, beautiful, powerful creatures up close was an incredible experience. I’m not sure I’d want to swim with them without the cage, but it seems that I likely have, many times. There are aerial photos of crowded beaches with huge sharks swimming in the depths below. They frequent the same coastal waters that we love to swim in. Something to think about next time you’re admiring the calm surface of the world’s oceans!
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