SHORT-FINNED PILOT WHALE (T) 



Globicephalamacrorhynchus Gray 1846 



Other Common Names 



Blackfish (see also p. 84, 91, and 94). 



Description 



Male short finned pilot whales of the western North 

 Atlantic reach lengths of at least 17.5 feet (5.3 m). Females 

 are reportedly slightly smaller than males (recorded only to 

 15.5 feet 14.7 m]). 



The head, somewhat like that of the Atlantic pilot whales 

 (p. 91), is thick and bulbous, a characteristic which reaches 

 its extreme in the development of a flattened or squarish 

 appearance to the front of the head in mature males (see 

 Fig. 101). In very old males the melon may overhang the 

 mouth up to several inches. The flippers are shorter than 

 those of the other pilot whale species of the western North 

 Atlantic (thus the common name short-finned pilot whale), 

 reaching only one-sixth of the body length or less. The tail is 

 dorsoventrally thickened just in front of the flukes. 



The dorsal fin, like that of the Atlantic pilot whale, is one 

 of the species' most distinctive characteristics. It is low in 

 profile, has a long base, and is set far forward on the animal's 

 back. 



Short-finned pilot whales are all black on the back sides 

 and most of the belly with an anchor-shaped patch of gray on 

 the chin and a gray area of varying extent and intensity on the 

 belly. These areas are less vivid and extensive than those on 



Atlantic pilot whales. Younger animals are lighter, often 

 medium gray. 



Natural History Notes 



Short finned pilot whales are known to occur in groups of 

 60 animals or more, though smaller groups are more common. 

 They have been reported pitchpoling (spy-hopping), lob- 

 tailing, and — rarely — breaching. 



Short-finned pilot whales feed on squid and fish. 



May Be Confused With 



In the tropical portion of their range, short- finned 

 pilot whales may be confused with pygmy killer 

 whales (p. 138) and many-toothed blackfish (p. 142). 

 They may be distinguished from both species pri- 

 marily by their distinctive dorsal fin and the bulbous- 

 to squarish head. Both pygmy killer whales and 

 many-toothed blackfish have dorsal fins, which are 

 more falcate, slender, and pointed on the tip, and have 

 longer, slenderer heads. 



Throughout their range short-finned pilot whales may be 

 confused with false killer whales. The two species may be dis- 

 tinguished by the same differences which distinguish Atlan- 

 tic pilot whales from false killer whales (p. 91). 



In the extreme northern portion of their range, 



Figure 100. — Short-finned pilot whales stranded in northeastern Florida, shown here swimming in the lagoon at Marineland of Florida. This 

 species, Uke their northern cousins, the Atlantic pilot whales, have a highly distinctive dorsal fin and a bulbous head (see Figs. 97, 99i. In these 

 photos note the variation in the shape of the head. Those of females and immature males are more rounded. Those of adult males are far more 

 blunted. (Photo courtesy of Marmeland of Florida.) 



94 



