Bull shark (Teddy Fotiou / CC BY)
Bull sharks (Carcharhinus leucas) have stout bodies and long caudal fins. They reach about 3.4 meters (11 feet) in length and 315 kilograms (694 pounds) in weight. Bull sharks have the highest bite force of all sharks. They are considered dangerous to humans (121 unprovoked attacks, 26 fatal). Bull sharks are probably responsible for the majority of fatal shark attacks on humans (mainly swimmers) in tropical coastal waters.