DENSE-BEAKED WHALE (T) 



Mesoplodon densirostris (Blainville in Desmarest 1817) 



Other Common Names 



None known. 



Description 



Dense-beaked whales reach alengthof at least 17 feet (5.2 

 m). The body is distinctly spindle-shaped. The head, the 

 contour of which is the most distinctive characteristic of this 

 species, is marked by a prominent rise, located near the angle 

 of the gape on each side. This rise, which bears the teeth, 

 gives a peculiar high, arching contour to the mouth (p. 84), 

 particularly in adult males. 



The flippers are small (one-eleventh to one-tenth the body 

 length) and have their origin in the lighter color of the lower 

 sides. The dorsal fin varies from small and triangular to 

 nearly falcate and pointed on the tip. It is located behind the 

 midpoint of the back. The flukes are from one-sixth to 

 one-fifth the body length, are seldom notched, and 

 occasionally even bulge slightly backwards near the center of 

 the rear margin. 



Dense- beaked whales are black or charcoal gray on the 

 back, slightly lighter on the abdomen. They are somewhat 

 blotched with grayish white and are often extensively 

 scratched or scarred. The flippers are lighter than the back. 

 The flukes are dark above, light below. 



Natural History Notes 



From stomach contents of stranded animals dense- beaked 

 whales are known to feed on squid. 



May Be Confused With 



Adult male dense-beaked whales can be separated from 

 the other beaked whales by the high, arching contour to the 

 corners of the mouth. If there is no adult male in the group, 

 however, dense-beaked whales may be confused with any of 

 the other beaked whales species. 



Distribution 



Dense beaked whales have been reported from Peggys 

 Cove. Nova Scotia south to Florida. From all accounts, this 

 species appears widely but sparsely distributed in warm 

 temperate seas. 



Stranded Specimens 



Adults of this species should be distinguishable by the 

 highly distinctive contour of the mouth. The teeth, located in 

 the high rise of the mouth, are oriented slightly backwards. 



Figure 83. — A dense-beaked whale in the tank at New York Aquarium. Note the position of the prominent dorsal fin, just breaking the surface. The blow of 

 beaked whales is usually small and inconspicuous and reportedly projects markedly forward from the head. {.Photo by J. G. Mead. ) 



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