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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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Great White Shark Cage Diving Daily Blog 20 April 2017 (Trip 1 + 2 + 3)

Thursday, April 20, 2017 |  0 Comment Tags: Cape Town, Gansbaai, Great white sharks, Kleinbaai, shark cage diving, sharks, sharkwatchsa, south africa, white sharks,

Author: Kelly Baker (Biologist)

Guest comment: “Thanks for a great trip! The friendly service made this trip perfect!” – Lisa

“Amazing! Worth the early morning wake up. Great service and fabulous staff. Very informative. *****” – Michael + Jenna

“It was the best day of my life. Thank you for making my dream come true!” - Laura

20/04/2017

Location: Joubertsdam                                                                                                                                                          

Water Temperature: 11.4’C + 11.6’C +  11.7'C

Depth:  10.5m + 10.7m + 10.0m

Visibility: 2.0m + 1.5m + 1.0m 

Number of Sharks: 3 + 1 + 3

Conditions: Little swell and slight east wind with bright, clear skies all day.

We were slightly anxious as to what today might hold for our White shark viewing as yesterday afternoon proved to be successful but a little slow. Working with wild animals means that we can never predict anything and many factors influence White shark sightings and behaviour. One such factor can be the presence of a larger predator in the area, as documented off the West coast of America twice and once off the coast of South Australia more recently as the White shark does have a natural predator in the form of Orcinus orca, more commonly known as the Killer whale or Orca. Whilst we are yet to witness such an attack on our White sharks in Gansbaai, we have observed some very interesting behaviour over the last few months in relation to Orcas presenting in the bay, for example the sightings of two Orcas, known as “Port” and “Starboard”, on the 8th of February, a day before we experienced a rare 23 day period of no White shark sightings (please see previous blogs here and here for information and theories on past shark scarcity in Gansbaai). These two Orcas have been seen by Marine Dynamics before, back in October and November of 2015 and at that time it appears we did not experience any flight response from our sharks and sightings continued. Yesterday our sister company, Dyer Island Cruises reported the same two Orcas in the bay, our research vessel, Lwazi, was launched and tracked the two, it appeared they were heading into deeper water past the Islands and we hoped their visit would not disrupt our sightings. This morning our first White shark appeared quite quickly with a male approximately 3.0m in length coming into view, he cruised by a few times before heading off. The second shark of this trip, a small juvenile, appeared more comfortable around the boat and stuck around longer than the previous one even making some close passes by the cage. The third and final shark of the trip was an estimated 4.0m female however much like our first shark, she appeared somewhat shy and would not approach closely but gave our group an impressive view of how large these animals can grow. A successful trip, we all had our fingers crossed the next two trips of the day would be the same and that our worries of no sharks would be dismissed.

The second trip of the day was an exclusive for a family of six visiting from the United States. We waited patiently and a juvenile appear after some time. A new individual for the day, she is sporting a number of parasite attachments to the trailing edge of the dorsal fin and some darkly pigmented markings on her head making her easy to identify. Whilst she did not stay with us the entire trip she did visit multiple times and made amazingly close and slow passes by the cage making for some beautiful views under water and to see nicely from on board. Another successful trip, could we make it three out of three?

The third and final trip of the day launched and three hours into the trip there had been no sightings. We were about to pack up and head back to Kleinbaai as the sun started to set down, when a shark appeared. We had a little juvenile around for a little while, so everybody could have a look at the shark from the boat and from the cage, how lucky. As the sun was setting we made our way back to the Kleinbaai harbour. 

Three out of three successful trips for Marine Dynamics

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