The main food source for Great Whites in the Med are Tuna, hence why they are seen near Sicily and Malta which include seasonal migration routes for Tuna in the Med. I saw a TV programme about La Matanza off Sicily where tuna are coralled into a system of nets before being pulled to the surface. One lucky guy has to dive in and close the nets at the bottom and the fishermen were saying that decades ago it was not uncommon for a whit shark to have followed the tuna into the nets. Having said that, they hadn't seen one in many years.....
Here is some info on a big white caught off Malta;
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