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  • Shark cage diving in Gansbaai, South Africa with Marine Dynamics. Experience the exceptional and come face to face with a great white shark! 

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

  • 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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Sharkwatch SA Blog

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Orca predation on Great White Shark in Gansbaai, South Africa

Author: Marine Dynamics (Shark Cage Diving Company)
Marine Dynamics is a Shark Cage Diving company based in Kleinbaai, a small harbour town, part of Gansbaai in the Western Cape of South Africa. This area is known as a hotspot for the Great White Shark and the best place in the world to see and dive with these iconic creatures in their natural environment.

On the 4th of July, the Marine Dynamics/Dyer Island Conservation Trust (DICT) was notified by Paul de Villiers of a white shark stranding at De Gruis, Gansbaai, South Africa. The carcass was recovered by Marine Dynamics owner, Wilfred Chivell, and his team, and transported to the International Marine Volunteer Lodge. The following morning a team lead by DICT marine biologists collected detailed measurements, photographic, and biological samples. The white shark was a 3.6 meter female with a large tear between the two pectoral fins with the liver and heart missing - identical injuries to that previously recorded on deceased white sharks in Gansbaai and other shark species found along the coast. Two days prior there were confirmed sightings in False Bay, Cape Town of the orca pair, Port and Starboard, known to predate on various shark species, including white sharks.

The carcass also showed signs of multiple shark bites along its pelvic area, likely a result of scavenging after the initial predation. There were no signs that fishing gear was responsible for the death and no tag was observed on the shark. The DICT team took multiple samples, including fin clippings, muscle, vertebrae, gills and jaws.

Much speculation has occurred regarding the disappearance of white sharks from Gansbaai over the past three years- and what has driven their absence. “We believe that commercial overfishing and removal of prey species has a critical impact on the number of white sharks and we are encouraged by the recent selection of an expert panel of scientists to advise the Department of Environmental Affairs, Forestry and Fisheries on addressing this matter. However, the impact of Orca predations on white sharks in Gansbaai is simply undeniable. It is not a smokescreen for a bigger issue but also linked to pressures other marine species are enduring, adding further urgency to the action on threats affecting the decline of shark stocks along the South African coast,” says Wilfred Chivell, CEO of Marine Dynamics. “The shark cage diving industry is key to daily monitoring of white sharks that can ultimately advise conservation policy. We have been proactive in setting up our COVID-19 safety protocols so we now await confirmation from government as to when we can start operating.”

Senior White shark biologist Alison Towner said, “We have monitored the behaviour and abundance of white sharks in the area for over 13 years through an established long-term boat-based and tagging data program. The interactions between orcas and white sharks were first observed in 2017 and seem to occur at similar times each year, although we are only seeing the shark carcasses that wash out, they are all notably larger white sharks, above 3 meters in length. This is concerning for a species that does not reach reproductive maturity until after this size. Collaboration between key experts, scientists, and stakeholders are paramount to proactively preserve the future diversity of Southern African shark populations and we thank the members of the public who have provided important information regarding these issues.”

Stranded Great White shark at De Gruis, Gansbaai
Great White shark carcass retrieval by Marine Dynamics team
Photogrammetry in process
Great White sharks have blue eyes
Marine biologists inspecting the Great White shark carcass
Data sheet
Great White shark dorsal fin
Marine biologists measuring the gills of a Great White shark
Marine biologists measuring the pectoral fins of a Great White shark
Laceration between the pectoral fins of the Great White shark
Bite mark wounds to the tail of the Great White shark
Marine biologists searching for organs of the Great White shark
No organs present in the Great White shark carcass
Great White shark dorsal fin
Parasite found in the mouth cavity of the Great White Shark
Great White shark eye lens
Vertebrae detail of the Great White shark tail
Marine biologists inspecting the Great White shark jaw
Great White shark teeth detail

Additional information:

White shark predation by orca reported in 2017:
Great White Sharks hunted by Orcas in Gansbaai
Great White Sharks hunted by Orcas in Gansbaai Continues

MARINE DYNAMICS TOURS is a shark cage diving company operational since 2005, that conduct and support valuable research, conservation and education in the Dyer Island ecosystem of Gansbaai, South Africa. The award-winning companies hold Fair Trade Tourism certification (since 2008) and employ marine biologists whose research is in turn supported through the DYER ISLAND CONSERVATION TRUST (DICT).  www.dict.org.za

Dyer Island and the surrounding ocean is a critically important ecosystem and home to the Marine Big 5. Known as an Important Bird Area, and managed by CapeNature, Dyer Island is home to breeding colonies of the endangered African penguin and other seabirds. Some 60 000 Cape Fur Seals are resident on Geyser Rock opposite the island and they attract the densest population of Great White Sharks in the world. The many sheltered areas of the bay provide the breeding ground for the Southern Right Whales that migrate here from the Sub-Antarctic islands between June and December each year. The area is also visited by Bryde’s and humpback whales as well as various dolphin species.

 

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