To about 13 ft (4 m).
- Head broadly arched and hammer-shaped, lacking indentation at midline ("smooth")
- Pelvic fins with straight to slightly concave rear margins
- Color deep olive to brownish-gray above, shading to white below
- Underbody of posterior portion of body may have numerous small dark spots on lighter-shaded areas
- No interdorsal ridge
Nova Scotia, Canada to Florida.
Coastal and offshore; from surface to at least 66 ft (20 m); tolerates much cooler waters than most hammerheads.
Bonnethead has shovel-shaped head; growns to about 5 ft (1.5 m). Scalloped Hammerhead and Great Hammerhead have prominent central indentations on anterior margin of head. Great Hammerhead attains larger maximum size (18.5 ft (5.6 m)); has very high first dorsal fin, pelvic fins with curved rear margins.
Text descriptions taken from:
Guide to Sharks, Tunas, & Billfishes
of the U.S. Atlantic and Gulf of Mexico