The Story of the incredible 20'000 kilometre journey of a female White Shark from South Africa to Australia and back…
In the late 1990’s, Michael Scholl was part of a scientific team that gathered White Shark tissue samples from South Africa, Australia and New Zealand. These tissue samples contained the genetic fingerprint of a sample of the international population, and their DNA was analysed at the University of Aberdeen in Scotland. The results from this study showed for the first time a connection between White Sharks from two continents: White Sharks from South Africa and Australia were closely related. The results of this astounding discovery were published in 2001 in the scientific journal Nature.
In 2002, an international team of scientists and organisations came together in an unprecedented collaborative effort with the common objective to better understand the movements of White Sharks in and out of South Africa, to be able to better protect this endangered species. Dr. Ramon Bonfil of the Wildlife Conservation Society (WCS) directed this research project in collaboration with the South African Sea Fisheries department (Marine and Coastal Management), the universities of Cape Town and Pretoria, the South African Museum IZIKO and the White Shark Trust.
From 2002 to 2004, forty-three White Sharks were tagged with various types of satellite tags (SPOT and PAT) around Dyer Island and in Mossel Bay. Most tagged sharks remained in relatively small areas along the coast of South Africa never venturing far out to sea, while some Sharks were swimming back and forth between known hot spots such as Dyer Island and Mossel Bay. Two Sharks even undertook a long trip along the African continent to the KwaZulu-Natal coastline, swam into international waters when they left the coast and the second Shark even entered the Mozambican waters where it lost the national protection status that South Africa offered. This was exactly the kind of evidence the team was trying to gather: the main objective of this study was to gather sufficient evidence showing that these Sharks do not respect artificial national boundaries set by human politics, and hence that broader international protection legislation was needed to adequately protect a wide roaming species like the White Shark rather than isolated national or regional protection status.
In November 2003, the team tagged a near four meter long female White Shark near Dyer Island with a PAT (Passive Archival Tag) satellite tag. This archival tag detached itself from the Shark at the end of February 2004 as programmed, and started sending all the stored information via satellite back to Ramon Bonfil’s computer in New York. She had swum over 10’000 kilometres from South Africa to the shore of another continent, Australia, crossing the entire Indian Ocean in just 99 days, which corresponded to an incredibly fast average swimming speed of at least 4.7 kilometres per hour. Her tag had detached itself from the Shark only a few kilometres off Ningaloo Reef, in the north western region of Australia.
When this shark left South Africa, she first swam several hundred kilometres to the South into the empty and vast ocean. She then turned east and swam in a very determined and incredibly straight pattern towards Australia, further supporting that these Sharks use very precise navigation senses. Her regular diving pattern from the surface to the deep oceanic waters along her journey indicates that she might be using celestial navigation with the sun, moon or stars, as well as maybe using landmarks from an imprinted earth magnetic field anomaly map. Moreover, she somehow managed to bypass the amazing dangers that barred her way: potential meetings with natural predators, Orcas, north of the Prince Edward and Marion Islands, the millions of long-lining hooks from the extensive tuna fisheries fishing fleets targeting mainly the western and central Indian Ocean, and finally the massive targeted shark fin fishing fleets in the eastern Indian Ocean with its own sets of millions of baited hooks.
This Shark was also well known to Michael Scholl and the White Shark Trust FinPrinting photographic identification database since 1999 as annual visits to Dyer Island showed a regular visitation pattern: she had visited the Dyer Island area every year between July and November. And as scheduled, she incredibly returned to Dyer Island six months after her satellite tag popped up in Australia. Following the molecular discovery in 2001 of a genetic link between White Sharks from South Africa and Australia, this was the first direct proof on how this link operates. Her journey there and back again across the Indian Ocean in nine months was an incredible adventure.
Ramon Bonfil named this Shark Nicole from the famous Australian actress Nicole Kidman who shares some keen liking to White Sharks. Nicole made the headlines of all major newspapers around the world in October 2005 following the publication in the scientific journal Science: first return transoceanic migration covering over 20’000 kilometres in nine months, deepest recorded dive at over 980 meters and record temperature of 3.4 degrees Celsius. Nicole has become more famous than Bruce, the most infamous White Shark of the movie Jaws.
But Nicole has strangely not been seen at Dyer Island since November 2004... What happened? Did she get caught in the maze of dangers along her next journey on one of the countless hooks spread across the Indian Ocean? Or did something in her life change and she simply altered her pattern? Nicole had grown over four meters long by the last time she was spotted, and she would soon have reached the length at which female White Sharks are believed to become sexually mature. The last time, Michael Scholl spotted Nicole in Shark Bay in November 2004, she presented some distinctive deep and extensive bite wounds on her body behind the gills, a feature that may be the result of an unlikely aggressive interaction with another White Shark, or more interestingly of mating (see Kayak section).
Read more about Nicole's incredible journey, in Michael Scholl and Thomas Peschak's book South Africa's Great White Shark...
And watch the National Geographic documentary Great White Odyssey on Nicole's voyage from South Africa to Australia...
