Bridled spotted dolphin, Cuvier's dolphin, gamin (St. Vincent), bridled porpoise.
Description
Bridled dolphins, the second species of spotted dolphins in the western North Atlantic, reach an adult length of at least 7 feet (2.1 m). Like the other, the Atlantic spotted dolphin (p. [104]), bridled dolphins are characterized by light grayish-white spots on the dark dorsal portions of the body and dark spots on the light ventral surface. Other details of the coloration differ somewhat. Bridled dolphins are dark gray on the back, fading to lighter gray on the sides and belly. They lack the spinal blaze characteristic of Atlantic spotted dolphins. Except on the head, the border between the back and side colors is indistinct. On the head, the cape (the dark color of the top of the head) is distinct. In the light gray of the side of the head are the markings from which the species derives its common name, "bridled dolphin." These are a black circle around the eye with an extension to the junction (apex) of the rostrum and the melon (present in nearly all dolphins) and a broad black stripe from the origin of the flipper to the corner of the mouth. This mouth-to-flipper stripe tends to fade as spotting increases. Both the upper and lower lips are white or pinkish.
Natural History Notes
Virtually nothing is known of the natural history of bridled dolphins except that they have been observed in small herds of from 5 to 30 individuals and sometimes ride the bow wave of a vessel.
May Be Confused With
At sea, bridled dolphins may be confused with Atlantic spotted dolphins or spinner dolphins. Differences by which they may be distinguished from the first are tabularized on p. [105]. Differences between spinner and bridled dolphins permitting identification at sea are as follows:
| Bridled Dolphin | Spinner Dolphin |
|---|---|
| COLORATION | |
| Distinct cape on top of head;side of head light gray;distinct stripes from flippersto corner of mouth and fromdark circles around eye toapex of melon. | Dark gray on back; tan oryellowish tan on sides; whiteon belly. |
| BEAK | |
| Shorter and more slender; allblack; lips white. | Extremely long and slender;dark gray to black on top,white below; lips black. |
| DORSAL FIN | |
| Uniformly dark gray. | Often lighter gray in middle,dark around border. |
Distribution
Bridled dolphins occur in tropical and subtropical waters primarily near coastal areas and islands, but are best known from the West Indies. They have been reported from the Antilles, from Texas, and from Florida north to North Carolina. It has been speculated that this species replaces the Atlantic spotted dolphin around the West Indies.