The relative risk of being attacked by a shark

The general public is at once fascinated and horrified by the idea of being attacked by a shark. News of an attack is often reported at least nation-wide, if not internationally. This dissemination by the media, compounded with the powerful image of the shark and the irresponsible journalism involved in the production of such "documentaries" as SHARK ATTACK!! lead people to fear swimming in the ocean. In fact, many vacationers will refuse to swim in the ocean for fear of being attacked by a shark. This fear is unfounded, as the risk of being attacked by a shark is infinitessimally small.

Worldwide, there are roughly 70-100 attacks by sharks upon humans annually and of these attacks, between 5-15 deaths will occur. This may seem like a large number, but in comparison with the number of people using the ocean recreatively, the risk of attack is extremely small.

It is difficult to determine exactly what the relative risk of attack by a shark is for any one bather, given that the number of bathers worldwide is uncertain. However, for a more restricted region some estimates may be made. We can make the following comparisons based on data available within the United States:

• For five states (Florida, Georgia, Louisiana, South Carolina and Texas):
  • During a time period spanning at least a decade for each state, there were 1.1 alligator attacks per annum, on average. These attacks resulted in 8 total fatalities. During the same time period, there were roughly 1.2 shark attacks per annum, but only 6 fatalities.
  • From 1959-1990, on average 16.1 people were struck by lightning per state per annum, resulting in an average of 4.6 deaths. During the same period, 1.35 people were attack by sharks per state per annum, resulting in an average of 0.032 deaths.
• Nation-wide, there were 18 people injured by Sharks in 1996. Over the same time period, there was an enormous number of people injured performing home repairs:
  • 198 849 injured by nails, screws, tacks or bolts;
  • 138 894 injured using ladders;
  • 43 687 injured by toilets;
  • 36 091 injured by gardening implements;
  • 13 458 injured by chain saws;
  • 15 957 injured by pliers or wire-cutters;
  • and 2 599 injured by room deodorizers
• In 1981, there were 12 shark attacks all across the United States. That same year, in New York City alone, there were:
  • 12 656 people bitten by dogs;
  • ~1 500 people bitten by humans;
  • 826 bitten by cats;
  • 60 bitten by wild rats;
  • 81 bitten by squirrels;
  • 52 bitten by hamsters;
  • 37 bitten by rabbits;
  • 18 bitten by raccoons;
  • 18 bitten by horses;
  • 17 bitten by gerbils;
  • 15 bitten by laboratory rats;
  • and 11 bitten by monkeys.

It could be mentioned that such risk comparisons are fallacious given that they do not involve recreational use of the water. It is also known, however, from Australian data, that the risks of drowning, being killed surfing, fishing or scuba-diving are far greater than being attacked by a shark.