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An Analysis of Shark Attacks
This paper will discuss why shark attack human beings and how they hunt in the environment that they live in. By analyzing the behavior of sharks, we can see that most attacks on human beings are mistakenly made for seals or other marine life that sharks prefer to eat. The fact that sharks may not even like the taste of human flesh is the framework in realizing that sharks are not the vicious killers that people think they are. Sharks do not attack people for pleasure, or even for food, but are mistaken identities for marine life and/or weather conditions that sharks do prefer to hunt in their environments.
There have been investigated “90 alleged incidents of shark-human interaction occurring worldwide in 2000.” (Allen p.112) Upon review, 79 of these incidents represented confirmed cases of unprovoked shark attack on humans. Unprovoked attacks are defined as incidents where an attack on a live human by a shark occurs in its natural habitat without human provocation of the shark. Shark-inflicted scavenge damage to already dead humans (most often drowning victims), provoked incidents occurring in or out of the water (usually involving divers or fishers handling sharks), and interactions between sharks and divers in public aquaria or research holding-pens are not considered attacks. The eleven 2000 incidents not accorded “unprovoked” status included four cases of attacks on marine vessels, four “provoked” attacks, two attacks listed as “doubtful,” and one in which insufficient information was available to assign it to category. These are some of the statistics that were gathered that can tell us that, based on the billions of people that are living in the world, that they do not occur that often and are usually provoked by people in professional situations. The yearly total of 79 unprovoked attacks was the largest tally since investigators began recording such statistics in 1958. By comparison, 58 unprovoked attacks were recorded in 1999 and the yearly average during the decade of the 1990's was 54. Since the late 1980's, the number of unprovoked shark attacks has grown at a steady rate, rising “from 38 in 1988 to all-time highs of 62 in 1994 and 74 in 1995.” (Allen p.67) Overall, the 1990's had the highest number of attacks (536) of any previous decade, continuing an upward trend exhibited throughout the twentieth century, yet leaves us still with a narrow margin for threat compared to these numbers.
The number of shark-human interactions transpiring in a given year is directly correlated to the amount of human time spent in the sea. As the world population continues to upsurge and the time spent in aquatic recreation greatly rises, we might expect an annual increase in the number of attacks. By contrast, near-shore shark populations are declining at a serious rate in many areas of the world as a result of over-fishing and are theoretically reducing the opportunity for these shark-human interactions. However, year-to-year variability in “local economic, meteorological and oceanographic conditions also significantly influences the odds of sharks and humans encountering one another.” (Ambrose p.55) As a result, short-term trends in the number of shark attacks must be viewed with caution, but may not be seen as a viable threat, but is not a reason why sharks wish to “target” human beings, which they do not have a tendency to do under the explanations given.
Most attacks occur in near-shore waters, typically inshore of a sandbar or between sandbars where sharks feed and can become trapped at low tide. Areas with steep drop-offs are also likely attack sites. Sharks congregate there because their natural food items also congregate in these areas. Usually, they are known to hunt seals and other forms of marine life such as these, but do not attack humans because of their flesh. As a matter of fact, sharks do not prefer the taste of human flesh in most cases because they do not like the taste of it.” (Allen p.88)
There are three major kinds of unprovoked shark attacks. By far the most common are “hit and run” attacks. These typically occur in the surf zone with swimmers and surfers the normal targets. The victim seldom sees its attacker and the shark do not return after inflicting a single bite or slash wound. In most instances, these probably are cases of mistaken identity (such as a seal) that occur under conditions of poor water visibility and a harsh physical environment (breaking surf and strong wash/current conditions). A feeding shark in this habitat must make quick decisions and rapid movements to capture its traditional food items. When these difficult physical conditions are considered in conjunction with provocative human appearance and activities associated with aquatic recreation (splashing, shiny jewelry, contrasting colored swimsuits, contrasting tanning, especially involving the soles of the feet), it is not surprising that sharks might occasionally misinterpret a human for its normal prey. We suspect that, upon biting, the shark quickly realizes that the human is a foreign object, or that it is too large, and immediately releases the victim and does not return. Some of these attacks could also be related to social behaviors unrelated to feeding, such as dominance behaviors seen in many land animals. Injuries to "hit and run" victims are usually confined to relatively small lacerations, often on the leg below the knee, and are seldom life threatening.
“Bump and bite” attacks and “sneak” attacks, while less common, result in greater injuries and most fatalities. These types of attack usually involve divers or swimmers in somewhat deeper waters, but occur in near-shore shallows in some areas of the world. “Bump and bite” attacks are characterized by the shark initially circling and often bumping the victim prior to the actual attack. “Sneak” attacks differ in having the strike occur without warning. In both cases, unlike the pattern for "hit and run" attacks, repeat attacks are not uncommon and multiple or sustained bites are the norm. Injuries incurred during this type of attack are usually quite severe, frequently resulting in death. We believe these types of attack are the result of feeding or antagonistic behaviors rather than being cases of mistaken identity. Most shark attacks involving sea disasters, e.g. plane and ship accidents, probably involve "bump and bite" and "sneak" attacks.
Greg Ambrose states: “that only about ten humans a year are killed by sharks worldwide (while humans kill at least 100 million sharks annually.)” (Ambrose p.114) He goes on to say that from 1779 to 1990, there were only 85 shark attacks in the Hawaiian Islands and only 36 resulted in fatalities. More of the victims were swimmers, and a large percent were people fishing on the shoreline when attacked. My point is that for all the millions of people in the ocean's waters every year, there are very few attacks on humans. You probably have a better chance at winning the lottery, or are more likely to see a flying saucer, than getting hit by a shark. The odds are in your favor that you will not be attacked.
In conclusion, we can see that most attacks that occur worldwide are no serious threat to understanding shark attacks and the amount that occur. The most interesting fact is that they are not even attracted to humans for the purpose of hunting, but see us as a mistaken identity for seals and other fish that the sharks normally hunt for. The idea that we are worried about shark attacks, save for the Florida region that has an increasing amount of shark attacks (possibly due to shark population growth), is due to the press and the nature of humans to panic because of propaganda that is way overreached.
Allen, Tom, Shark Attacks: Their Causes and Avoidance, Globe Pequot Press, January 2001.
Allen, Tom, The Shark Almanac, Globe Pequot Press. 2003
Ambrose, Greg, Shark Bites: True Tales of Survival, Bess Press, The, December 1996.
Compagno, Leonard. Dando, Marc. Fowler, Sarah. Shark of the World, Princeton University Press, 2005
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