The Atlas of North American Freshwater Fishes describes the bull shark (Carcharhinus leucas) as an aggressive shark that reaches 10 feet in length and has been known to attack man. Its range extends as far up the Mississippi River as Alton, Illinois.
According to the Illinois Department of Conservation, two commercial fishermen from Alton, Herbert Cope and Dudge Collins, caught a bull shark in 1937. They found something troubling their wood and mesh traps late that summer. Concluding that it was a fish, they built a strong wire trap and baited it with chicken guts.
The next morning, they caught a 5-foot 84-pound shark, which they displayed in the Calhoun Fish Market where it attracted crowds for days. Although some folks suspected a hoax, the catch was considered authentic. Biologists later concluded from photos that it was a bull shark. Recently, Clint Smith of Alton supplied an old photo of the catch, with the present-day ADM flourmill in the background.
Bull sharks can live a long time in freshwater. In 1972, one was caught 2,500 miles up the Amazon. The journey from New Orleans to Alton is about 1,750 miles. Dams now prevent sharks from entering Illinois.