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Sharks are one of the most feared species in the ocean and have received a bad rap from most. However, most scientists believe the attacks on humans are unintentional. Shark attacks can be categorized into different situations in which humans are attacked. If you have a better chance of being attacked in certain situations, can attacks be prevented? It is unlikely that you could prevent attacks altogether; however, I will analyze different situations in which more unprovoked attacks occur. Often the amount of attacks can be contributed to the number of people in the water, but also to the amount of sharks and types of sharks in the water. Data will show the correlation between these factors and will show how threatening sharks really are.
Shark attacks around the world seem to be more focused in areas of high surfing and a large number of tourists. North America is the leading region of which shark attacks occur. By far the leader in this area is Florida. The reason for the large amount of attacks in this area is because of its long coastline (>1200 miles) and it houses many different types of potentially dangerous species of sharks. This is also a hotspot for attacks because of the amount of people in the water at any given time whether they are residents of the area or tourists.
Of the large number of unprovoked shark attacks that do occur, many occur with surfers. This is mainly because of the nature of their actions. Surfers generally spend more time in the water and venture further off shore. Also, the way they paddle and swim on the surfboard may give the sharks a confusing visual of their prey. Therefore, it should be of no surprise that other hotspots for attacks are also popular surfing spots. Other regions that have incurred a large portion of unprovoked attacks are regions like South Africa, Australia, Brazil, Hawaii, California, and New Zealand. Coincidently a few of these regions are home to one of the most dangerous sharks of all, the Great White Shark, which is said to be responsible for more than a quarter of all shark attacks on people. The home to most of the Great White Sharks is centered in South Africa, Australia, and California. Also, the prey of choice of these animals is a seal, which one could argue that a surfer on the surface may resemble such a creature.
There is interesting information and correlation between the depths of the water and the distance from shore of unprovoked attacks on humans. Some of the information I present is somewhat irrelevant because for example, snorkelers wouldnÕt be more than 30 feet below the water. However, taking the limitations and locations of the swimmers into account the information can be somewhat helpful to understand. Breaking the ÒswimmersÓ into groups like scuba divers and snorkelers makes it easier to see why the data may represent what it does.
Shark attacks on scuba divers seem to be more centered on middle to shallow depth range. Data suggests that the deeper the water, the lower rate of attacks. Again this could be because a majority of the scuba divers are diving in middle range depths. The highest number of attacks occurred on divers at depths between 11-20 feet, the second highest being between 0-5 feet. However, it seems, as though between 31-50 feet has a fairly high rate of attacks. This is about the cut off of depth before the rate starts to drop significantly. Perhaps more useful is the total water depth of the diver. The highest amount is at 51-60 feet; however, seven different ranges are close and are sporadic. There is a drop between 100-150 feet but is on a rise at 150 feet plus. Again this may be indicative of where the scuba divers are diving.
Perhaps more useful statistics can be found with attacks on snorkelers and free divers. The depth of the swimmer between 0-5 feet is significantly the highest rate of attacks on humans. However, snorkelers are usually snorkeling in this range giving the highest chance of being attacked within this range. There are some attacks in deeper water, however it declines rapidly. The total water depth of the attacks on these types of swimmers is probably much more helpful. The most popular depth is between 11-20 feet, suggesting this may be the most popular depth of these types of swimmers. There is a steady increase up to this range and then declines >20 feet, but is still a fairly high rate until depths >40 feet. This data can be conclusive when thinking about the depths at which most swimmers will be, but also because some sharks pursue prey closer to shore and some more towards the open ocean. Perhaps a closer look at which types of sharks will attack at these coinciding depths would be more useful.
Another statistic that has an interesting correlation between attacks on humans by sharks are the activities that the swimmers are doing while being attacked. Most attacks seem to be focused on snorkelers and free divers. This could be because more people snorkel as opposed to SCUBA dive. SCUBA diving only represents 30% of the unprovoked attacks on humans while snorkelers account for over 45% of the attacks on divers. This could show some evidence that the splashing on top of the water or visual the shark gets from a snorkeler may look more like prey than a SCUBA diver. However, these statistics may again just be because of the number of swimmers participating in those activities.
Surfer attacks are on the rise when looking at the percentage of the attacks from decade to decade. Throughout 1980 to the present surfing attacks accounted for over 50% of the unprovoked attacks. Before to this time period, surfing was just gaining popularity and could be the reason that the percentage of the surfing victims rose rapidly between 1970 and 1980. However, the surfer victim percentage has slowly declined between 1980 and the present.
The question that remains is why are the victims more likely to be attacked doing certain activities as opposed to others, or if they even are. The reason that surfers become such a target is because compared to other swimmers they tend to spend more time in the ocean and venture further off of the shore. Most scientists believe that the attacks on humans are because of a judgment error on the sharkÕs part. After all, we are intruding on the sharkÕs natural hunting environment. As I have said before, the look that a surfer may give from below could resemble a sharkÕs prey, such as a seal or sea lion. Also, there are some theories that smaller sharks could be attracted to the swimmerÕs palms and the bottom of their feet. These areas of the body tend to be a lighter color than a wet suit or darker skin color. The smaller sharks may confuse this area for the flashing white of fish. Swimmers on the surface tend to be more attractive to sharks then divers underneath the water.
Most shark attacks are not fatal; this is because sharks do not see us as food and more than likely do not like the taste of our flesh. Also, sharks do not have hands to feel their food before they eat it and do not know if what they are going for initially is edible. This is why sharks usually do an exploratory bite to see if the prey is edible. Unfortunately, sometimes sharks do not stop there and these exploratory bites can be fatal by themselves. These exploratory bites are considered hit-and-run attacks. Sharks actually prefer prey that consists of high fat content; even an obese person would not have the fat content that a shark would be looking for.
Another type of attack is a bump-and-bite attack. These types of attacks prove to be more dangerous and fatal. This occurs when a shark will come up to its possible prey and bump into it while investigating. The skin of a shark can be coarse and could cause a wound on the victim causing blood to pour into the water. Blood in the water with a shark is extremely dangerous and triggers them to attack, this time more fatal. The third type of attack is a sneak attack and is as dangerous as the bump-and-bite attack. In this situation the shark attack occurs without warning. This type of attack also occurs mostly with the more dangerous sharks such as the great white, tiger, or bull shark.
According to statistics regarding the most attacks by any one shark shows that out of all of the unprovoked attacks, three sharks are responsible for a majority of them. The three sharks considered most dangerous in order, is the great white shark, the tiger shark, and the bull shark. The most dangerous, the great white shark was responsible for 254 unprovoked attacks (67 were fatal). This number is unmistakably a lot larger than the closest of any sharks, the closest being the tiger shark who was responsible for 91 unprovoked attacks (29 were fatal). The last of the three most dangerous is the bull shark that was responsible for 66 unprovoked attacks (20 were fatal). The next four dangerous sharks in order are the sand tiger shark, the blacktip shark, the hammerhead shark, and the blue shark. These statistics were based on attacks between the years 1580 and 2000. (Carwardine, p. 104)
According to the sharks usual habitats and their degree of danger towards humans, the sharks that are most threatening in the Florida and Caribbean area are discussed in the following. The most dangerous sharks in the specified region are the Tiger Shark, Oceanic Whitetip Shark, and the Bull Shark. These sharks are considered extremely dangerous and caution should definitely be used. A unique characteristic of the Bull Shark is that it can roam in fresh water. Tiger sharks have been known to eat just about anything and have reportedly contained numerous unusual items in their stomach. The Oceanic Whitetip Shark is famous for its attack on the Navy after the U.S.S. Indianapolis was sank by the Japanese, causing numerous deaths during this feeding frenzy.
The next two sharks are considered to be dangerous and are also in the Florid, Caribbean area. These two sharks are the Shortfin Mako and the Copper Shark. The Mako Shark is a fast and deadly shark that can reach speeds of around 25 mph and bursts of speed up to 45 mph. This quick and deadly shark should be considered very dangerous and caution should be used. The Copper Shark is also considered dangerous and caution should be used with this species as well. Following those five dangerous sharks, there are four more that come close when it comes to the degree of danger, which include the Sand Tiger Shark, Lemon Shark, Blue Shark, and the Great Hammerhead Shark. However, this tropical area enjoys many different species of sharks that are potentially dangerous and should not be taken lightly by any means. This list includes the Blacknose Shark, Bignose Shark, Silky Shark, Carribean Reef Shark, and the Whitetip Shark.
In conclusion, all sharks should be handled with caution especially if you do not know what you are doing. You should always be aware of your surroundings and never underestimate a shark. Even though sharks are not hunting us, we may get caught up in search for a lunch. Sharks can be very interesting and amazing creatures, but they can also be lethal, deadly, and vicious.
Works Cited
Allen, Thomas B. Shark Attacks Their Causes and Avoidance. New York, NY: The Lyons P, 2001.
Andrea., Ferrari,. Sharks. Toronto, Ont: Firefly Books, 2002.
Benchley, Peter. Shark Trouble. New York, NY: Random House, 2002.
Carwardine, Mark. Shark. Wood Lane, London: Firefly Books, 2004.
Carwardine, Mark. The Shark Watcher's Handbook. Princeton, NJ: Princeton UP, 2002.
Musick, John A., and Beverly McMillan. The Shark Chronicles. New York, NY: Times Books, 2002.
Perrine, Doug. Sharks & Rays of the World. Stillwater, MN: Voyageur P, 1999.
Perrine, Doug. Sharks. Stillwater, MN: Voyageur P, 2002.
"Ichthyology Department." Florida Museum of Natural History. 16 May 2009 Compagno, Leonard, Marc Dando, and Sarah Fowler. Sharks of the World. Princeton, NJ: Princeton P, 2005.
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Johnson, R.H. Sharks of Tropical and Temperate Seas. Pisces Books, 1992.
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