Seasonal arrival and feeding of injured coastal sharks at fish farms in the eastern Mediterranean
Adi Barash, Renanel Pickholtz, Hagai Nativ, Shahar Malamud, Aviad Scheinin, Dan Tchernov
Leon Charney School of Marine Sciences, University of Haifa, Haifa, ISRAEL
School of Zoology, Tel Aviv University, Tel Aviv, ISRAEL
Morris Kahn Marine Research Station, Sdot-Yam, ISRAEL
Every summer coastal sharks (mostly sandbar sharks, Carcharhinus plumbeus) come to feed at open-sea fish farms near the Israeli coast, ever since their opening. Three of these sharks appear to suffer injuries of various degrees. At least one of the injured individuals, which suffers from a broken lower jaw, has been sighted at the fish farms every year since 2011. Providing a constant source of food to supplement feeding of wildlife has been shown to have both negative and positive impacts on wild populations and individuals. It may be possible that injured sharks, who have reduced abilities to find food in the wild, rely on such human related food sources to survive. Implications on the long-term effect of provisional feeding on sharks are discussed.
Keywords: Carcharhinus plumbeus, provisional feeding, elasmobranch, aquaculture, Eastern Mediterranean
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