There is no one eating pattern for sharks. Over the 450 million years that shark species have evolved, modern shark species that exist today have adapted to specific environmental niches. Some species of sharks eat once every few weeks, and others  aren’t predators at all, they filter plankton out of the water. Sharks have a long evolutionary lineage that has never included humans as a reliable food source for any species of shark. Unlike opportunistic terrestrial predators such as lions or crocodiles, we have not co-evolved with sharks, who have adapted to very specific food webs. Read more...

For example, great white sharks have evolved to eat various species of seals and sea lions. Human beings are not on the menu. Great whites have what is known as a “bite, spit, and wait” behavior. They lurk beneath the surface, and when prey is sighted, they accelerate quickly to the surface, take a bite, and wait before returning to feed. Great whites have been observed with injuries from the teeth and claws of elephant seals and sea lions who fight back, so a strategy of "bite first, eat later" results in fewer injuries to the shark. The vast majority of great white incidents involving humans consist of just one bite and a hasty departure.

According to Dr. John McCosker, senior scientist at the California Academy of Sciences, White Sharks can sense after a fraction of a second into its first bite the caloric value of its potential prey. The shark quickly determines whether the “catch” has the right caloric values to warrant the energy to attack it further and eat it. Human beings generally don’t have enough body fat to interest a shark. [1]

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