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  • In Gansbaai, the largest white shark ever caught was at Danger Point and measured up to 5.9m. The exact world record white shark is a contested issue, but chances are it is between 6-7m.

  • If you see a white shark in the water don’t panic. Chances are high that the shark has already detected you and isn’t interested. White shark attacks are normally associated with poor visibility, so avoid murky conditions.

  • White sharks have a unique system called a “counter current heat exchange”, which keeps their body  tempreture +/- 7C above the surrounding water temperature. 

  • All sharks have an incredibly unique system on the tip of their nose called the “ampillae of Lorenzini”. These are small pores filled with a gel that transmits the electrical currents in the water to the shark’s brain so that it can assess its environment.

  • White sharks give birth to live young (not eggs), and they give birth to 6-8 pups at one time. Pups are usually between 1.0-1.5m in length and are born with teeth.

  • Body language has been a well documented form of shark communication and has identified body arching, jaw gaping, and other postures as specific social tactics.

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When is a white shark sexually mature?

Tuesday, June 12, 2012 |  0 Comment Tags: puberty, sexually mature,

Author: Michelle Wcisel (Marine Biologist)
To Michelle, a born and bred American from Michigan, the sea resembles another planet within Earth where intelligent "extraterrestrial" beings and thriving systems flourish in the depths where there is neither oxygen nor sunlight. "So many of us gaze at the stars in wonder when we should be looking into our oceans!"

White shark sexual maturity is a topic of much debate and the more we think we know, often the more questions we create.  Puberty in sharks is related to size more than age.  Past research has indicated that most female white sharks above 4.5m in length are sexually mature and males above 4.0m.  We know white sharks are very slow growing animals, so it may take upwards of 10-15 years for these animals to reach this sexually mature size. 

However, a recent research expedition held in the Gansbaai area blew this subject wide open.  Dyer Island Conservation Trust marine biologists, Alison and Oliver, recently boarded the M/V Ocean to partake in a tagging campaign held by Ocearch.  During the tagging, sharks were lifted on a platform and blood samples as well as sperm samples were collected.  The team was shocked when a "small" 3.2m male had calcified claspers full of sperm.  Certainly, this shark was ready to mate, but would he be able to manage a +4.5m female? It could be that white sharks do reach sexual maturity at a smaller size than previously thought, but they may not be able to handle the big girls...

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