Great White Sharks

jawsGreat White Sharks can be found in every ocean on the planet.  They are described as some of nature’s perfect predators.    They grow to lengths of about 20 feet, and can weigh up to 3 tons.  Great white sharks are in the mackerel shark family.  They are closely related to mako sharks, salmon sharks, and porbeagles.  Mackerel sharks have an unique ability among sharks that allows them to raise their blood temperature much higher than that of the surrounding water, giving them the ability to be more effective killers.

Colossus the shark

“Colossus” the shark attacking a seal decoy set out by scientists at Seal Island, South Africa.

Unlike most sharks that hunt fish, great whites specialize in hunting seals and other marine mammals.  They are most commonly found near large seal colonies, such as in the Faralon Islands, Seal Island, the Neptune Islands, Guadalupe, the East coast of North America, and New Zealand.  They are ambush predators.  They locate prey by scent, the lateral line on their sides that detects movement, the ampullae of lorenzini on their snouts that detect the electricity emitted by all living animals, and sight.  They swim deep under water and see the silhouette of seals above them.  Then, they  shoot up from the depths at speeds of over 20 mph and bite the seal’s tail end with over 5,000 psi! They retreat and let their target bleed out, and then consume it with their serrated teeth.  Their teeth fall out on a regular basis, and are replaced by new ones often.

Great white sharks have got a bad rap from the movie Jaws, which depicts a man eating shark preying upon humans.  As a result, sharks were hunted to not let humans fall victims to sharks massive jaws.  The author, Peter Benchley, did not intend for people to hunt sharks.  He just wanted to scare people with a good old fashion terror movie.  He then decided to help sharks out and raise awareness to the amazing features of sharks.  Ironically, he was the first host of Shark Week, a week dedicated to raising awareness to sharks.