Dr Mario Lebrato had released the oceanic black tip shark back into waters just off the coast of Spain, however it was soon ambushed.Scientists were left in disbelief after spotting a 'zombie shark' still hunting for food - despite being half-eaten in an attack by other sharks. Dr Mario Lebrato had released the oceanic black tip shark back into waters just off the coast of Spain, however it was soon ambushed. The 35-year-old believes that the attack was carried out by bull sharks, which can weigh up to an incredible 400kg, according to the Mirror. Incredibly, the black tip shark...