At sea the Atlantic spotted dolphins may also be confused with rough-toothed dolphins (p. [135]).
Distribution
Atlantic spotted dolphins are a common species in the continental waters of the tropical and warm temperate western North Atlantic. Although they are far more abundant south of Cape Hatteras, they have been reported from the latitude of Cape May, N.J. (some fishermen claim to have seen them even further north) south through the Gulf of Mexico and the Caribbean to Venezuela. Atlantic spotted dolphins may be replaced around the West Indies by the bridled dolphin.
Within this range, the Atlantic spotted dolphins appear to be generally restricted to the waters outside the 100-fathom curve, most commonly more than 5 miles offshore. However, populations in the Gulf of Mexico move inshore in the late spring, and may approach close to shore during spring and summer.
Stranded Specimens
Stranded Atlantic spotted dolphins may be difficult to distinguish from bridled dolphins. If the color pattern is still clearly visible, the differences in coloration described above, particularly those of the head, and the presence or absence of a spinal blaze may be used. But since external appearance other than coloration are often very similar, specimens should be photographed from as many aspects as possible and the entire specimen or the roughed-out complete skeleton transported to a museum for preparation and examination. Tooth counts recorded for the two species to date are also very similar.