Off the beaches of Capetown, South Africa, sharks appear in great numbers each year to feed on seals and dolphins. However, attacks on humans have increased which is being blamed on tour operators offering the chance to "swim" with the sharks from the safety of a cage. Large quantities of bait are dropped which attract the sharks in their numbers.
Theory is, this kind of activity means the shark is now associating food with humans who are now considered 'dinner'.
the total number of shark attacks annually worldwide has remained fairly constant at between 50 and 60.
There's no doubt that there's a correlation between the numbers of people using the sea and the number of unprovoked attacks in some regions, but taken overall the statistics tend to confirm that unprovoked shark attacks are extremely rare when viewed in the context of the huge numbers of people swimming in the sea each year, and not all shark attacks are fatal.