Ce bébé requin blanc à été capturé en février 2015 proche de la Turquie… en Méditerranée.
Il est relâché en mer.
Be prepared to hear a fascinating piece of natural history about the Mediterranean great white sharks (Carcharodon carcharias). Story is fascinating for multiple reasons. First, great whites are one of the most charismatic, vulnerable, cryptic and misunderstood predator fish species. Second, the story takes place in a quite unexpected location. Altınoluk is a town on the northern Aegean coast of Turkey. It is located to the south of Troy on a legendary sea route known as the Argonaut route where Jason and the Argonauts went on an epic adventure in search of the golden fleece.
Evolutionarily, sharks are very ancient going back to 400 million years. Great whites however have evolved quite recently during the Miocene period at about 20 million years ago. Shark biologists have debated for more than 150 years whether the ancestral origin of the great whites were from the Megalodons. A recent study of a 4 million year old shark fossil from Peru have shown that great whites were more related to mako sharks and didn’t evolve from Megalodon sharks.
As a biologist who studied gene flow hearing about extreme cases have always inspired me. In July 2008 fishermen of Altınoluk contacted marine scientists about two newborn great white sharks they caught. A research team from the Bosphorus and the Istanbul University collaborated with an international team of shark scientists and made a genetic analysis on the tissue taken from the pups. Results published in 2010 have confirmed that sharks were not siblings. When their genetic make-up were compared against a global database it turned out that they were most related to the Australian population. Further genetic analysis also revealed another very striking fact. The Mediterranean population remained isolated for about 450 thousand years. This is indeed an ancient and epic walkabout from an ocean half a world away literally.
On July 6th 2011, fishermen of Altınoluk caught another great white pup and this time it was alive. Before releasing her back to nature they did a great job of documenting this extremely rare and endangered specimen. Biologists have had some curiosity whether certain locations in the Mediterranean may serve as a nursery for great white sharks. Generally for top predators greatest mortality for the young comes from predation. Females may prefer to give birth to their young in places where adult population is minimal so that their pups find refuge. For example the Sicilian channel, near the Italian island of Lampedusa, is one such location where both pregnant females and newly born great whites have been reported. With three pups caught in trammel nets for two consecutive summers Altınoluk must be marked on the map as a nursery for the great white. For instance, Boncuk Bay in southwestern Turkey is a known nursing ground for the sandbar sharks
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