Wikipedia describes the bull shark (Carcharhinus leucas) as a requiem shark commonly found worldwide in warm, shallow waters along coasts and in rivers. It is known for its aggressive nature, and presence in warm, shallow brackish and freshwater systems including estuaries and rivers.
Long known for its aggressive tendencies, the bull shark is considered even more dangerous for its ability to migrate up rivers. It is able to survive for long periods of time in freshwater and has popped up as unwelcome visitors in rivers across the world.
One such place is the Potomac River, which runs along the Atlantic coast of the United States.
Per reports, a commercial fisherman named "Wily" Dean found an 8-foot long bull shark caught in his net in 2010. While this incident occurred in Cornfeld Harbor, the same fisherman got a dead bull shark in his nets 3 years later but this time at Point Lookout State Park in Maryland. That same day, Dean noticed a massive shadow underneath his boat which was yet another bull shark again. Unfortunately, it died upon capture.
This excerpt explains how the events unfolded: Three years later, Dean was fishing near Point Lookout State Park in Maryland when he discovered another dead bull shark trapped in his nets. A biologist happened to be with Dean at the time and took the shark back to shore to study. Later that same day, Dean saw something large and dark in the waters near his boat—a second bull shark! Although this one was alive when it was discovered, it died shortly after being pulled from the water."
In a different incident that occurred in 2017, fisherman Larry “Boo” Powley landed a massive 8.6-foot bull shark that weighed an impressive 310 pounds in St. Mary’s County in southern Maryland. Per reports, this was his first during his 42 years of experience as a fisherman: "Powley, who has been on the water for 42 years, said he was planning to catch his usual crop of menhaden, a common fish often used in fish oils for humans and bait for blue crab. Menhaden measure 15 inches at most, so the 8.6-foot-long bull shark that got stuck in his trap off Cedar Point, in St. Mary’s County, around sunrise wasn’t hard to notice. "
The shark was released back into the water following a quick photo shoot.