The Science of Shark Attacks

"I just felt a big bump. As I was turning my head I was thinking maybe a turtle another surfer. I don't think a turtle could bump me that hard. So then I turned and sort of saw the shark pop up and went over my arm and I went under water. I could feel the tips of the teeth pretty sharply. They first touched my skin and then went through, and I couldn't feel anything."

The shark that attacked Jesse was a Tiger and like most species its teeth are perfectly adapted for cutting through tough skin and muscle. Jesse was bitten and let go - the shark clearly didn't want to make a meal of him. So why was he attacked? Was it a case of mistaken identity? Some scientists believe that if the animal's motivated to feed then what's the risk in going up and taking a little taste. Jesse's attack took place in open deep water. He had no defence against the shark that struck him silently from below. The bite left Jesse's arm so badly mutilated it's still on the road to recovery. After 2 years, he still doesn't have full mobility.

With over to 100 attacks and 10 deaths a year, protecting ourselves from shark attacks is becoming ever more important. Over the last few years the largest increase in shark attacks has been along the eastern coast of America. The summer of 2001 witnessed sharks moving in to shallow waters and striking swimmers near the shoreline. In just 3 weeks there were 20 attacks and 2 deaths - often in water no more than 3 feet deep. Everyone wants to know if it was because there were more people in the water or because the sharks were becoming more aggressive?

We may never know the answer but scientists from State Longbeach believe we could reduce the number of attacks if we knew more about their feeding habits. Their research could help us judge what times of the day it's most dangerous to get in to shark-infested waters. The scientists are not convinced by the popular theory that sharks only feed at the beginning and end of the day. The sharks' stomach contains acid that varies in concentration depending on how hungry they are. The weaker the strength, the bigger their appetite. Using a metal probe, packed with microelectronics, they plan to look into the digestive habits of a shark. They plan to feed the probe to a shark and record the times of the day when stomach acid levels are at their weakest. Then they'll know when the shark is hungriest and most dangerous. By gutting a squid and hiding the probe inside, they hope to fool the shark into swallowing it whole. Then by tracking and down loading data remotely, they'll be able to pin point exact feeding times on any shark.

There's still much to learn about the science of shark attacks. Those who have lived through the nightmare have drawn their own conclusions about when it's safe to swim. Science and technology may be able to help us - but one fact is certain. As more and more of us take to water, the number of shark attacks is going to increase.

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