Shark attacks!!!


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Shark attacks!!!

  2. 2. A shark attack is an attack on a human by ashark. Every year around 100 shark attacksare reported worldwide. Seventeen fatalitiesare recorded as having being caused by sharkattacks in 2011, out of 118 recordedattacks.[1] Despite their relative rarity, manypeople fear shark attacks after occasionalserial attacks, such as the Jersey Shore sharkattacks of 1916, and horror fiction and filmssuch as the Jaws series. Almost all sharkexperts consider that the danger presentedby sharks has been exaggerated. The creatorof the Jaws phenomenon, Peter Benchley,attempted to dispel the myth of sharks beingman-eating monsters in the years before hisdeath
  3. 3. Although Australia is rankedthe second highest in terms ofglobal shark attacks with 877attacks, it is ranked thehighest in terms of sharkfatalities, with 217fatalities.[3][4][5] Australia hadthe most shark attacks in2008, with 48 attacksAustralia wide; 11 of thesewere fatal. The highest deathrate occurred in Queenslandwith the total of 6 fatalattacks.[6] In 2000, there were79 shark attacks reportedworldwide, 11 of them fatal
  4. 4. Types of attacksShark attack indices use different criteria to determine if an attackwas "provoked" or "unprovoked." When considered from thesharks point of view, attacks on humans who are perceived as athreat to the shark or a competitor to its food source are all"provoked" attacks. Neither the International Shark Attack File(ISAF) nor the Global Shark Attack File (GSAF) accord casualties ofair/sea disasters "provoked" or "unprovoked" status; theseincidents are considered to be a separate category.[31][32]Postmortem scavenging of human remains (typically drowningvictims) are also not accorded "provoked" or "unprovoked"status.[32][33] The GSAF categorizes scavenging bites on humans as"questionable incidents."[32] The most common criteria fordetermining "provoked" and "unprovoked" attacks are discussedbelow:
  5. 5. Provoked attackProvoked attacks occur when ahuman touches a shark, pokes it,teases it, spears, hooks, or nets it, orotherwise aggravates/provokes it in acertain manner. Incidents that occuroutside of a sharks natural habitat,e.g., aquariums and research holding-pens, are considered provoked, as areall incidents involving capturedsharks. Sometimes humansinadvertently "provoke" an attack,such as when a surfer accidentally hitsa shark with a surf board.
  6. 6. Unprovoked attackUnprovoked attacks are initiated by the shark—they occur in a sharks natural habitaton a live human and without human provocation.[31][32] There are three subcategoriesof unprovoked attack:Hit-and-run attack – Usually non-fatal, the shark bites and then leaves; most victims donot see the shark. This is the most common type of attack and typically occurs in thesurf zone or in murky water. Most hit-and-run attacks are believed to be the result ofmistaken identity.[34]Sneak attack – The victim will not usually see the shark, and may sustain multiple deepbites. This is the most fatal kind of attack and is not believed to be the result ofmistaken identity.[34]Bump-and-bite attack – The shark circles and bumps the victim before biting. Repeatedbites are not uncommon and can be severe or fatal. Bump-and-bite attacks are notbelieved to be the result of mistaken identity.[34]An incident occurred in 2011 when a 3-meter long great white shark jumped onto a 7-person research vessel off Seal Island, South Africa. The crew were undertaking apopulation study using sardines as bait, and the incident was judged to be an accident
  7. 7. Large sharks species are apex predators in their environment,[36] and thus have little fear ofany creature they cross paths with. Like most sophisticated hunters, they are curious whenthey encounter something unusual in their territories. Lacking any limbs with sensitivedigits such as hands or feet, the only way they can explore an object or organism is to biteit; these bites are known as exploratory bites.[37] Generally, shark bites are exploratory, andthe animal will swim away after one bite.[37] For example, exploratory bites on surfers arethought to be caused by the shark mistaking the surfer for the shape of prey.[38]Nonetheless, a single bite can grievously injure a human if the animal involved is apowerful predator like a great white or tiger shark.[39]Despite a few rare exceptions,[40][41] it has been concluded that feeding is not a reasonsharks attack humans. In fact, humans dont provide enough high-fat meat for sharks,which need a lot of energy to power their large, muscular bodies.[38]Sharks normally make one swift attack and then retreat to wait for the victim to die orexhaust itself before returning to feed. This protects the shark from injury from a woundedand aggressive target; however, it also allows humans time to get out of the water andsurvive.[42] Shark attacks may also occur due to territorial reasons or as dominance overanother shark species, resulting in an attack.[43]Sharks are equipped with sensory organs called the Ampullae of Lorenzini that detect theelectricity generated by muscle movement;[44] another theory is that the sharks electricalreceptors, which pick up movement, pick up the signals like those emitted by wounded fishfrom someone who is fishing or spearfishing, and thus attack the person by mistake.[43]George H. Burgess, director of the International Shark Attack File, said the followingregarding why people are attacked: "Attacks are basically an odds game based on howmany hours you are in the water".[45]
  8. 8. avoiding the water at dawn, dusk, or night,when sharks tend to feed;avoiding areas where sharks generally locatethemselves, such as murky waters, sandbars,and steep drop-offsavoiding swimming alone, always being near agroup of people, and if possible, avoidingscattering the group;refraining from excess splashing or movement;preventing pets from entering the water;avoiding shiny jewelry, tan lines and brightclothing, all of which can attract sharks;avoiding entering water if bleeding from anopen wound or if menstruating;avoiding areas where prey animals of sharkslive, for instance seals;avoiding areas where the remains of fish havebeen discarded into the water, such as nearfishermen cleaning their catch.avoiding waters contaminated with sewage orrunoff and areas frequented by sport orcommercial fisherman