Shark attack

For the film, see Shark Attack (film).

A blacktip reef shark. In rare circumstances such as bad visibility, blacktips may bite humans, mistaking them for prey. Under normal conditions, however, they are harmless and often even quite shy.

A shark attack is an attack on a human by a shark. Every year, a number of people are attacked by sharks, although most survive. Despite the relative rarity of shark attacks, the fear of sharks is a common phenomenon, having been fueled by the occasional instances of attacks, such as the Jersey Shore shark attacks of 1916, and by sensationalized fiction and film, such as the Jaws series. Many shark experts feel that the danger presented by sharks has been exaggerated, and even the creator of the Jaws phenomenon, the late Peter Benchley, attempted to dispel the myth of sharks being man-eating monsters in the recent years before his death.

Statistics

In 2000, there were 79 shark attacks reported worldwide, 11 of them fatal. In 2005 and 2006 this number dropped to 61 and 62 respectively, while the number of fatalities dropped to only four per year. Of these attacks, the majority occurred in the United States (53 in 2000, 40 in 2005 and 38 in 2006). For the same period, the Global Shark Attack File records 69 unprovoked attacks of which five were fatal.

The Florida Museum of Natural History points out that these numbers should be compared with the much higher deaths from other, less feared causes; for example, several hundred people die annually from lightning strikes. It should also be noted that the relatively low number of shark attacks on humans is dwarfed by the number of sharks fished by humans, amounting to almost 40 million per year.

The New York Times reported in July 2008 that there had been only one fatal attack in the previous year.

Species involved in incidents

Contrary to popular belief, only a few sharks are dangerous to humans. Out of more than 360 shark species, only four have been involved in a significant number of fatal unprovoked attacks on humans: the great white, tiger, oceanic whitetip shark and bull shark. These sharks, being large, powerful predators, may sometimes attack and kill people; however, they have all been filmed in open water by unprotected divers.

Modern day statistics show the oceanic whitetip shark as being seldom involved in unprovoked attacks. However, there have been a number of such attacks in the past, particularly during World War I and World War II. A possible explanation is that the oceanic whitetip lives in the open sea and rarely shows up near coasts, where most incidents occur nowadays. During the world wars many ship and aircraft disasters happened in the open ocean, and due to its abundance the oceanic whitetip is often the first species on site when such a disaster happens.

Infamous examples of oceanic whitetip attacks include the sinking of the Nova Scotia, a steamship carrying 1000 that was sunk near South Africa by a German submarine in World War II. Only 192 people survived, with many deaths attributed to the oceanic whitetip shark. Another example was the torpedoing of the USS Indianapolis on 30 July 1945, giving a minimal figure of 60–80 killed by oceanic whitetips. Some survivors stated that tiger sharks were involved too.

Watson and the Shark by J.S. Copley, based on an attack on a swimmer in Havana in 1749

In addition to the four species responsible for a significant number of fatal attacks on humans, a number of other species have attacked humans without being provoked, and have on extremely rare occasions been responsible for a human death. This group includes the shortfin mako, hammerhead, Galapagos, gray reef, blacktip reef, lemon, silky, and blue sharks. These sharks are also large, powerful predators which can be provoked simply by being in the water at the wrong time and place, but they are normally considered less dangerous to divers and swimmers than the previous group. A few other shark species do attack people every year, producing wounds that can potentially kill, but this occurs either specifically because they have been provoked, or through mistaken identity due to water conditions or the like.

Reasons for attacks

While one should be very cautious with great white sharks, it does not target humans as prey.

There are many theories about why sharks sometimes attack people. Sharks are apex predators in their environment, and thus have little fear of any creature they cross paths with. Like most sophisticated hunters, they are curious when they encounter something unusual in their territories. Lacking any limbs with sensitive digits such as hands or feet, the only way they can explore an object or organism is to bite it. Generally, shark bites are exploratory, and the animal will swim away after one bite (Nontheless, a single bite can grievously injure a human if the animal involved is a powerful predator like a Great White or Tiger shark.)

Most sharks would not waste energy attacking a human with the intention of eating them, as our ratio of bone-to-muscle makes us extremely hard to eat for a creature with no leverage (in open water, with nothing to prop a large prey item up against and no grasping limbs that could hold it still, it is quite difficult to remove flesh from bones using only their mouth).

Some species, such as the great white shark, may sometimes mistake humans for seal or other prey animal; this would be typical when a shark attacks a surfer. The shape of a surfer lying on a board closely resembles a seal from beneath the surface (seals have a thick layer of energy-rich fat, which makes them very attractive targets). Another theory is that sharks normally make one swift attack and then retreat to wait for the victim to die or exhaust itself before returning to feed. This protects the shark from injury from a wounded and aggressive target; however, it also allows humans time to get out of the water and survive.

Sharks are equipped with sensory organs that detect the electricity generated by muscle movement; another theory for the low fatality rate of shark bites is that the electrical receptors, which pick up movement, do not pick up the same signals from a human as they do a wounded seal (which creates a disturbance in the water similar to a human swimming), and so they are more cautious .

Dolphins' protection

There are many stories that tell of dolphins protecting humans from shark attacks, with multiple eye-witness accounts from survivors dating from antiquity to present day (typically, dolphins form a ring around humans who are injured or endangered). This phenomenon was declared "plausible" by the team of Discovery Channel's Mythbusters, where it was shown that a shark will attack no creature when a dolphin is around. However, in spite of years of scientific study, there has been no conclusive explanation given for this behavior. In some cases, sharks have been seen attacking, or trying to attack dolphins.

See also

• 1992 Cageless shark-diving expedition
• Jersey Shore shark attacks of 1916
• List of fatal, unprovoked shark attacks in the United States

External links

• Map of Shark Attacks updated regularly
• Shark Attack Survivors Shark Attack Education and Prevention
• - All Australian shark attacks on record. Open data base.
• International Shark Attack File
• Global Shark Attack File
• Shark attack information, statistics, and pictures
• How to fend off a shark
• Shark Attack - Why sharks attack, types of shark attacks, and how you can avoid a shark attack.
• Shark Attacks Underwater Photographer