SADDLEBACK DOLPHIN (T) 



Delpkinus delphis Linnaeus 1758 



Other Common Names 



Saddleback porpoise, common dolphin, crisscross 

 dolphin. 



Description 



Saddleback dolphins reach a maximum overall length of 

 about 8.5 feet (2.6 m) though most individuals are less than 

 7.5 feet (2.3 m) long. Males are slightly larger than females of 

 the same age. 



The body shape varies slightly but usually closely re- 

 sembles 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 aiid 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 thespinner 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, myetophids, 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 



Back basically black or 

 brownish; distinct white 

 chest or belly patch; hour- 

 glass or crisscross pattern on 

 sides, some tan to yellowish 



COLORATION 



Back from light g^ay to dark 

 gray to bluish gray; sides 

 gray; belly gray or white; 

 distinctive black lateral 

 striping from 1) eye to 



tan; distinct 

 from flipper 

 lower jaw. 



black stripe 

 to middle of 



nipper, 2) eye to anus, and 3) 

 dark color behind dorsal fin 

 forward, towards but not 

 reaching head. 



LENGTH 



To 9 feet (2.7 m). 



To 7.5 feet, rarely to 8.5 feet 

 (2.3-2.6 m). 



From a distance, saddleback dolphins might also be 

 confused with spinner dolphins because of the habits of both 

 species of congregating in large schools with much jumping 

 and splashing. Both species ride the bow wave, and close 

 examination should permit positive identification using the 

 following characteristics: 



Saddleback Dolphin 



Spinner Dolphin 



COLORATION 



Dark gray on back; tan or 

 yellowish tan on sides; white 

 on belly; lacks crisscross 

 pattern on sides; distinct 

 black stripe from flipper to 

 eye. 



Dark gray to brownish gray 

 on back; white on belly with 

 crisscross or hourglass pat- 

 tern of tan to yellowish tan 

 on side; distinct black stripe 

 from flipper to middle of 

 lower jaw. 



Distribution 



Saddleback dolphins are widely distributed in the 

 temperate, subtropical, and tropical waters of the western 

 North Atlantic Ocean. They have been reported off 

 Newfoundland, Iceland, Nova Scotia, and the coast of 

 Massachusetts, south along the coast of North America to the 

 Caribbean (West Indies and Jamaica), in the Gulf of Mexico, 

 and from South American waters at least to Margarita Island, 

 Venezuela. 



The species' occurrence in the more northerly portions of 

 this range during the summer and early fall months appears 

 to coincide with the intrusion of warm waters into those 

 areas. They are not uncommon off Nova Scotia in summer 

 and fall and are casual members of the marine mam- 

 malian fauna of the remaining Maritime Provinces during 

 that period. 



In previous years, saddleback dolphins were not 

 uncommonly encountered by collectors of Marineland of 

 Florida working the northeast coast of Florida, but the 

 species has been conspicuously absent since about 1960. 

 Reasons for this apparent shift of range are unknown. 



Stranded Specimens 



Saddleback dolphins have from 40 to 50 small, sharply 

 pointed teeth in each side of both the upper and lower jaws. 

 These numbers overlap with only those of the striped and 

 spinner dolphins (with 43-50 and 46-65, respectively). 

 Saddleback dolphins should be readily distinguishable from 



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