If you think that just because you're swimming in freshwater that you're safe from sharks, think again.
Not only do bull sharks roam as freely through freshwater as they do in saltwater, but bull sharks have been found as far inland as Indiana in the Ohio River and Illinois in the Mississippi River. Along with the great white shark and the tiger shark, bull sharks are among the top three species most likely to attack humans.
There are also at least five other species of true river sharks that are exclusive to freshwater rivers in Southeast Asia and Australia. All river sharks are capable of growing to over 10 feet in length, and are more than capable of consuming a human.