Other Common Names 



None known. 



Description 



Northern bottlenosed whales reach a length of 32 feet (9.8 

 m) and are robust in form. They are characterized by a 

 bulbous forehead, which is more pronounced on larger 

 animals and most distinctive in adult males, and by the 

 dolphinlike beak displayed in animals of all sizes and ages, 

 which is sometimes visible as the animals surface steeply to 

 breathe. 



The blowhole is located in an indented area behind the 

 bulbous forehead, and the blow emanating from it projects 

 upward or slightly forward to a height of up to 6 feet (1.8 m), 

 is bushy and is visible from a considerable distance under low 

 wind conditions. The dorsal fin, located two-thirds of the way 

 back on the back, reaches at least 12 inches (30.5 cm) in height 

 and is distinctly falcate. The dorsal fin may be visible from a 

 distance of several hundred meters. 



Northern bottlenosed whales are usually brownish in 

 color, though the markings change with age. Smaller animals 

 are a uniform chocolate brown. Larger animals retain the 

 chocolate brown color on the back but are often lighter on the 

 sides and the belly and often have irregular patches or 

 blotches of grayish-white coloration on the back and sides. 

 Extremely large animals, presumably older males, often 

 have a white head. The flippers and the undersides of the 

 flukes are uniformly brown in color. 



Natural History Notes 



Northern bottlenosed whales often form tightly packed 

 groups of up to 10 or more animals. This species holds the 

 anecdotal record for the longest dives, having been reported 

 by early whalers to remain submerged over 2 h. They are 

 probably deep divers, feeding primarily on squid (though 

 they may take fishes as well), and they rarely go in water 

 shallower than 100 fathoms (183 m). 



After a long dive, northern bottlenosed whales will 

 sometimes remain on the surface for 10 min or more, blowing 

 at regular intervals before making another dive. After the 

 last blow of a series or when the animals are startled by a 

 boat, they may show the tail flukes as they begin to dive. The 

 flukes are not notched on the rear margin. 



Northern bottlenosed whales have been observed to show 

 curiosity about boats, coming to them from a considerable 

 distance. They have also been observed to "lobtail," raising 

 the tail flukes above the water and slapping them against the 

 surface, and to jump clear of the water. 



In the late 19th century, after stocks of bowhead whales 

 were severely reduced by overwhaling, northern bottlenosed 

 whales became a prime target of arctic whalers. They were 

 sought because in addition to whale oil produced from the 

 body blubber, the forehead of the species yielded quantities 

 of spermaceti like that obtained from sperm whales. 



NORTHERN BOTTLENOSED WHALE (T) 



Hyperoodon ampullatus (Forster 1770) 



May Be Confused With 



Northern bottlenosed whales have a northerly and 

 deep-water distribution. Within their range, they may be 

 confused at a distance with minke whales, with sperm 

 whales, or perhaps with North Sea beaked whales. 



Minke whales (p. 63) have a falcate dorsal fin located in 

 approximately the same position as that of the northern 

 bottlenosed whale. However, minke whales have a flathead in 

 front of their two blow holes and are black to dark gray 

 on the back. 



Sperm whales (p. 57) have a squarish head that may 

 somewhat resemble that of an adult male northern 

 bottlenosed whale. However, there are numerous character- 

 istics which will permit these species to be distinguished even 

 from a distance: 



Northern 

 Bottlenosed Whale 



Sperm Whale 



BLOW 



Low and bushy; projects 

 upward from indentation on 

 top of head. 



Low and bushy; projects 

 obliquely forward from left 

 side of head; usually less 

 than 8 feet (2.4 m). 



Lighter brown; adults splot- 

 ched with grayish white; 

 body smooth. 



COLORATION 



Brownish gray; 

 pears wrinkled. 



body ap- 



FLUKES 



Rarely notched; seldom rais- 

 ed on long dive. 



Notched; raised on long dive. 



HEAD 



Tapering in younger ani- 

 mals; bulbous in adults; 

 white in older animals; beak- 

 ed. 



Squarish, long, al; 

 beakless. 



black; 



A further aid to distinguishing northern bottle- 

 nosed and sperm whales at sea is the fact that the 

 sperm whales that are found in areas where northern 

 bottlenosed whales are encountered are usually older, 

 larger males from 40 to 60 feet (12.2 to 18.3 m) long. 

 Northern bottlenosed whales do not exceed 32 

 feet (9.8 m). 



Northern bottlenosed whales may also be confused with 

 the poorly known North Sea beaked whale (p. 82). When 

 they can be examined at close range, however, northern 

 bottlenosed whales should be distinguishable on the basis of 

 the distinctly bulbous forehead. 



Distribution 



In the western North Atlantic, northern bottlenosed 

 whales are restricted to Arctic and north temperate waters, 



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