Dusky Shark
Common Name: Dusky Shark
Scientific Name: Carcharhinus obscurus
Size
To about 12 ft (3.7 m).
Distingushing Characteristics
First dorsal fin sloping, originating over or slightly before free tips of pectoral fins
Second dorsal fin with free tip length rarely more than twice fin height
Color gray or bluish-gray above, white below
Interdorsal ridge
Distribution
Cape Cod, MA, and Georges Back to FL, including Gulf of Mexico and Caribbean Sea.
Habitat
Continental waters inshore to outer continental shelf and adjacent oceanic waters
Similar Species
Sandbar shark, and bignose shark have higher first dorsal fins originating farther forward. Sandbar shark, most difficult to distinguish, attains smaller maximum size. Bignose shark has longer snout. Silky shark has second dorsal fin with free tip length usually more than twice fin height. Night shark has green eyes. Bull shark and Spinner shark lack interdorsal ridges.