Other dolphins, like the orca, hunt and kill seals, walruses, and even other dolphins. They all swallow their prey entirely or in big pieces. Sharks are dangerous enemies for a dolphin. Mankind may be the biggest enemy of the dolphin. In some coutries, dolphins are caught or killed for food.
Pollution is another threat caused by man.
Poisenous chemicals which pollute the oceans or seas may infect the fish which serve as food for the dolphins. Scientific research has proven that these chemicals also have affected the health of dolphins and developed tumors. Pollution has been the cause of death of many dolphins which have stranded on our beaches. Saving dolphins by scaring them Every year tens of thousands to hundreds of thousands of dolphins die in fishing nets as unintended catch. Some of these deep drift nets are more than a mile long.