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(continued)
The boy’s last—only—thought was that he had been punched in the stomach. The breath was driven from him in a sudden rush. He had no time to cry out, nor, had he had the time, would he have known what to cry, for he could not see the fish.
-Jaws, Peter Benchley
“SHARK!” The word echoed loudly against the cliff walls. Ken, Anita, and Alan had reached the turn around point and looked up to see David waving his arms in and out of the water. Laurene turned toward David. The shark’s dorsal fin slid silently between them. Laurene swam up to David. He was floating on his back, blood gushing from his massive leg wounds. Laurene struggled to keep David afloat, but Ken, Alan, Anita, and Diana quickly arrived at David’s side. Ken told Anita to go to the beach for help. She swam off with Laurene close behind. Ken, Alan, Ryan, and Andrew pulled David toward the shore.
He is still alive. After less than five minutes they reached the beach, where a lifeguard was already driving up. As David lay on the beach, blood seeped into the sand. A few minutes passed. David lost consciousness. The ambulance crew arrived and they attempted to resuscitate David. Ken, Anita, Alan, and the other swimmers waited for news. The arteries in both his legs had been severed in the attack, and at 7:49 a.m. on April 25, 2008 David Martin bled to death on Tide Park beach.
For days he has dumped a trail of tuna blood into the ocean so that a great white shark might be lured, so that we might touch its fin. The power of the primitive is parallactic.
-The Great White Shark, Arthur Sze
To understand a white shark attack, we must look at more than one point of view. The human view is tragedy; a deadly animal committed an unprovoked attack on an innocent person. David Martin’s death was sudden and heartbreaking. A grandfather, a friend, an athlete was taken by the awesome power of nature, which seldom touches man in such dramatic ways. A man who committed his life to helping animals as a veterinarian had been killed by the very thing he strove to help. Tragedy in this situation is unavoidable. Tragedy usually leads to sorrow, but sometimes it can lead to anger.
The shark has become an enemy. News articles, television reports, and even films portray the shark as a vicious, indiscriminate hunter. Over the years people have begun to discover the reasons why the attacks happen, but neglect to understand the shark, and thus become angry. To calm this anger, we must look at the other point of view; the view of the shark as a being of nature.
When white sharks attack humans, they are merely doing what they have done for millions of years: hunting. They are following their instincts. The shark that sealed David Martin’s fate just happened to be in the area, maybe for giving birth or maybe just passing by. White sharks are not territorial and in fact are notorious travelers. One shark was tagged off the coast of South Africa and then tracked to Australia and back within a year. The shark that killed Martin investigated the swimmers because its senses picked up their splashing. From the shark’s point of view, constant splashing at the water’s surface usually means an animal in distress and an opportunity for an easier-than-normal meal. So the shark investigated the splashing and saw a group of large, slow-moving animals (humans only swim around two to three miles per hour).
When the shark looked up at humans’ fairly large bodies, it saw only dark silhouettes with barely distinguishable shapes. To a shark, a silhouetted human looks much like a silhouetted seal or sea lion. White sharks’ vision, while good in comparison to other marine animals, is still poor because it is underwater vision. Light travels far less distance in water than in air, so even fish that have evolved for millions of years underwater are not sharp-sighted.
After locating potential prey, a white shark may choose to attack, or may not. White sharks, like other sharks, only feed when they need to. When white sharks hunt they do so instinctively; stalking their prey in the shadowy depths, then moving with a single fast, hard-hitting jolt and concluding with a devastating bite. If the shark is happy with its prey, it will let go of it, circle it, waiting for it to die so as to avoid any conflict or injury during consumption. If the shark is dissatisfied with its victim, it will abandon the prey and not waste any more valuable energy.
The white shark is the largest predatory fish on the planet, and being so requires massive amounts of energy. It is not clear how much food white sharks need during a given day, but we can figure that their diet must consist of animals that are rich in fat and blubber, like seals and porpoises, to correspond to their high energy requirements. Humans might initially look like a good meal to the shark, but are comparatively low in fat and have no blubber. Humans are not really on the white shark’s diet, but every time we step into the ocean we are venturing into the white shark’s hunting grounds. Because the beach is thought of as a tranquil recreation spot, people forget about the shark and its possible dangers.
Ignorance of sharks is not only reserved for beachgoers, however. Scientists will tell you that sharks as a species have been widely under-researched; the same is true for most marine species. Because of the lack of research, protection for the shark is hard to come by. Only sharks classified as endangered species are protected and luckily, the white shark is now protected. This, however, only came about because of the massive fishing for shark that coincided with the release of the 1975 film Jaws.
Without protection, many shark species can become threatened relatively easy. Most shark species are known as apex predators, or top-of-the-food-chain hunters. We have learned from studying evolution that apex predators usually have long gestation periods. Additionally, the job of an apex predator is to moderate the prey animals in its ecosystem by hunting them. In order to achieve a balance between predator and prey, predators (who hunt and kill many prey animals in their lifetimes) give birth far less often than prey animals because prey animals must replenish their population as a result of being constantly hunted. In short, sharks birth infrequently and usually to few pups. Therefore, when humans fish for sharks, the results are far more detrimental to the shark population than fishing for a prey fish like sardines is to the sardine population.
The destruction of sharks is also devastating for ocean ecosystems as a whole. Most sharks, being apex predators, are what are known as keystone species. This means that sharks affect the population of every species in their ecosystems, either directly or indirectly. In layman’s terms, white sharks eat sea lions, sea lions eat squid, squid eat krill, and krill eat phytoplankton. If there were fewer white sharks, then there would be more sea lions, which would result in fewer squid and more krill and so on . Without sharks, the entire balance of the ocean could go out of whack.
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