Scientific Name(s): Carcharhinus leucas (bull shark, Carcharhinus obscurus (Dusky Shark)
Nicknames: Bull, Dusky, Grey Shark
General Abundance (Peace River): Common- Abundant
Typical tooth size: Under 1 inch
Max Tooth Size: Over 1 inch
Facts:
+"Bull" sharks are named such after their short, broad snouts and tendency to bump prey with their nose before biting (to identify potential food items, as they have poor vision in murky waters).
+Bull sharks are one of the few sharks that can tolerate salt water as well as freshwater with no salt; they have been sighted 2,500 miles (4,000 km) up the Amazon River, as far north as Illinois up the Mississippi river. They are also known to inhabit some lakes.
+Bull, dusky, and sandbar sharks may often be confused when seen in the flesh. Unlike dusky and sandbar sharks, bull sharks lack an interdorsal ridge (raised flap of skin between the dorsal fins) and dusky sharks tend to have smaller dorsal fins than sandbar sharks.
+Bull sharks are one of the few shark species to be dangerous to humans, as they commonly inhabit shallow estuarine waters and tend to be aggressive.
+Bull shark: Max weight: ~ 700+ lbs (heavier than most sharks of comparable size), Max Length: ~ 13(+?) feet
+Dusky Shark: Max Weight: ~750 lbs, Max Length: ~14 feet
Sources:
http://www.dnrec.delaware.gov/fw/Fisheries/Documents/Delaware%27s%20Most%20Commonly%20Misidentified%20Sharks.pdf
http://animals.howstuffworks.com/fish/sharks/bull-shark3.htm