To about 8 ft (2.4 m).
- First dorsal fin large, triangular, originating over or slightly before pectoral insertion
- Pectoral fins large, broad
- Snout shorter than width of mouth
- Color brownish-gray or brown above, white below
- Interdorsal ridge
Cape Cod, Massachusetts to Florida, including Gulf of Mexico and Caribbean Sea.
Inshore shallow coastal waters, including bays, harbors, and estuaries; typically in waters 5-180 ft (2-55 m); also offshore, occasionally to 600-810 ft (183-247 m); bottom dwelling.
Blacktip shark, spinner shark, and bull shark lack interdorsal ridges. Dusky shark, most difficult to distinguish, attains larger maximum size (12 ft (3.7m)); has proportionally smaller, swept-back fins, with first dorsal fin farther back over free tips of pectoral fins. Bignose shark has longer snout, smaller first dorsal fin. Silky shark has smaller first dorsal fin, which is rounded, swept back, and set farther behind free tips of pectoral fins; second dorsal fin free tip length usually more than twice fin height.
Text descriptions taken from:
Guide to Sharks, Tunas, & Billfishes
of the U.S. Atlantic and Gulf of Mexico