The body shape varies slightly but usually closely resembles that of the striped dolphin (p. [113]). The dorsal fin varies from nearly triangular to distinctly falcate and is pointed on the tip. It is sometimes all black and sometimes black on the borders with a lighter grayish region of varying size near the middle.
The back is basically black or brownish black, but this coloration and the extent of the striping patterns that form the impression of a saddle and the degree of color distinction between the different zones are highly variable.
The chest and belly are cream white to white and are the most distinctive features from a distance. Up close, the sides will be seen to be distinctly marked with an hourglass or crisscross pattern of tan or yellowish tan. This crisscross pattern is diagnostic for the species.
The rostrum is intermediate in length and shape between that of the spinner and that of the striped dolphin and is often black with a white tip.
Natural History Notes
Saddleback dolphins are often seen in herds of a thousand or more and are often very active, many animals leaping clear of the water at any time. Like spinner dolphins, saddleback dolphins are active bow-riders and often come to the boat from considerable distances. Once on the bow they often ride for extended periods of time.
Saddleback dolphins feed on squid and on a variety of fishes, including anchovies, myctophids, and hake.
May Be Confused With
Saddleback dolphins might easily be confused with striped dolphins and must be examined closely to be distinguished from them. Primary differences apparent in encounters at sea are as follows:
| Saddleback Dolphin | Striped Dolphin |
|---|---|
| COLORATION | |
| Back basically black orbrownish; distinct whitechest or belly patch; hourglassor crisscross pattern onsides, some tan to yellowishtan; distinct black stripefrom flipper to middle oflower jaw. | Back from light gray to darkgray to bluish gray; sidesgray; belly gray or white;distinctive black lateralstriping from 1) eye toflipper, 2) eye to anus, and3) dark color behind dorsalfin forward, towards but notreaching head. |
| LENGTH | |
| To 7.5 feet, rarely to 8.5 feet(2.3-2.6 m). | To 9 feet (2.7 m). |