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Where Sharks Attack

According to the International Shark Attack File (ISAF), there are probably 70-100 shark attacks worldwide each year resulting in about 5-15 deaths. The number of attacks is only "probably" because not all shark attacks are reported, information from Third World countries is especially poor, and in other areas efforts are sometimes made to keep attack quiet for fear of bad publicity.

Shark attack is a potential danger that must be acknowledged by anyone that frequents marine waters, but it should be kept in perspective. Bees, wasps and snakes are responsible for far more fatalities each year. In the United States, the annual risk of death from lightning is 30 times greater than that from shark attack. For most people, any shark-human interaction is likely to occur while swimming or surfing in nearshore waters. From a statistical standpoint the chances of dying in this area are significantly from many other causes — such as drowning and cardiac arrest — than from shark attack. Many more people are injured and killed on land while driving to and from the beach than by sharks in the water. Shark attack trauma is also less common than beach-related injuries such as spinal damage, dehydration, jellyfish and stingray stings and sunburn.

For example, in Florida from 1959-1990, there were 1,155 lightning strikes that caused 313 fatalities while there were 180 shark attacks that caused four fatalities. And in Florida from 1948-1995, there were 218 alligator attacks that caused seven fatalities while there were 276 shark attacks that caused six fatalities.

The ISAF investigated 90 alleged incidents of shark-human interaction occurring worldwide in 2000. Upon review, 79 of these incidents represented confirmed cases of unprovoked shark attack on humans — attacks on a live human by a shark occurring in its natural habitat without human provocation of the shark.

The yearly total of 79 unprovoked attacks was the largest tally since the ISAF began recording such statistics in 1958. By comparison, 58 unprovoked attacks were recorded in 1999 and the yearly average during the 1990s was 54. Since the late 1980s, 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. Overall, the 1990s had the highest number of attacks — 536 — of any previous decade, continuing an upward trend exhibited throughout the twentieth century.

More than two-thirds of the attacks (69.6 percent, 55 attacks) occurred in North American waters with 51 from the U.S. and four from the Bahamas. Elsewhere, attacks occurred in Australia (7), South Africa (5), Reunion (2), Papua New Guinea (2), Tanzania (2), Fiji (1), Galapagos Islands (1), Japan (1), Kiribati (1), New Caledonia (1) and Tonga (1).

Following recent patterns, most unprovoked attacks within the U.S. occurred in Florida with 34 Additional U.S. attacks were recorded in North Carolina (5), California (3), Alabama (2), Hawaii (2), Texas (2), Louisiana (1), Puerto Rico (1) and South Carolina (1).

Within Florida, Volusia County had the most shark incidents with 12, which is largely attributable to high aquatic recreational utilization of its attractive waters by large numbers of Florida residents and tourists, especially surfers. Other counties having attacks in 2000 were Palm Beach with six, Brevard had four, Monroe had three, Indian River had two, St. Johns also had two, Lee, Manatee, Pinellas, Santa Rosa , and St. Lucie each had one.

The single U.S. fatality occurred in Pinellas County, Fla.

Swimmers-waders (46.1percent of cases with victim activity information) and surfers-windsurfers (31.6 percent) were the recreational user groups most often subjected to shark attack in 2000. Other attacks involved divers/snorkelers (18.4 percent) and body surfers (2.6 percent). A single attack (1.3 percent) occurred during a water entry event.

Almost any large shark, roughly two meters or longer in total length, is a potential threat to humans. Three species, however, have been repetitively implicated as the primary attackers of man: the white shark, tiger shark and bull shark. According to the ISAF, from 1580 to October 2000, the white was implicated in 254 unprovoked attacks resulting in 67 fatalities, the tiger was implicated in 83 unprovoked attacks resulting in 29 fatalities and the bull tiger was implicated in 69 unprovoked attacks resulting in 17 fatalities.

Although the relative risk of a shark attack is very small, shark attack is a hazard that must be considered by anyone entering the marine domain and risks should always be minimized whenever possible in any activity. The ISAF says chances of having an interaction with a shark can be reduced if one heeds the following advice:

  • Always stay in groups since sharks are more likely to attack a solitary individual.
  • Do not wander too far from shore — this isolates an individual and additionally places one far away from assistance.
  • Avoid being in the water during darkness or twilight hours when sharks are most active and have a competitive sensory advantage.
  • Do not enter the water if bleeding from an open wound or if menstruating — a shark's olfactory ability is acute.
  • Wearing shiny jewelry is discouraged because the reflected light resembles the sheen of fish scales.
  • Avoid waters with known effluents or sewage and those being used by sport or commercial fisherman, especially if there are signs of bait fishes or feeding activity. Diving seabirds are good indicators of such action.
  • Sightings of porpoises do not indicate the absence of sharks — both often eat the same food items.
  • Use extra caution when waters are murky and avoid uneven tanning and bright colored clothing — sharks see contrast particularly well.
  • Refrain from excess slashing and do not allow pets in the water because of their erratic movements.
  • Exercise caution when occupying the area between sandbars or near steep dropoffs — these are favorite hangouts for sharks.
  • Do not enter the water if sharks are known to be present and evacuate the water if sharks are seen while there. And, of course, do not harass a shark if you see one!

    The International Shark Attack File is a compilation of all known shark attacks that is administered by the American Elasmobranch Society and the Florida Museum of Natural History. The American Elasmobranch Society is a professional organization comprised of international workers studying sharks, skates and rays. More than 3,200 individual investigations are currently housed in the File, covering the period from mid-1500's to present. Many of the data in the File originate from the voluntary submissions of numerous cooperating scientists who serve worldwide as regional observers. Regional observers forward investigations of attacks in their areas for integration into the File. Data submitted to the File is screened, coded and computerized. Hard copy documentation, including original notes, press clippings, photographs, audio/video tapes, and medical/autopsy reports, is permanently archived. The File is utilized by biological researchers and research physicians; access to the data is granted only after careful screening on a case-by-case basis.

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