BOWHEAD WHALE (B) 



Balae-immysticetus Linnaeus 1758 



Other Common Names 



Greenland whale, Arctic right whale, great polar whale. 



Description 



Bowhead whales, so-called because of the high-arching 

 jaws and the resultant contour of the head, reach a maximum 

 length of about65feet(19.8m). They are extremely robust in 

 form. 



When viewed from the side, some swimming bowhead 

 whales show two characteristic curves to the back: the first 

 extends from the tip of the snout to just behind the blowholes; 

 the second, encompassing the entire back, begins just behind 

 the head and extends all the way to the tail. This character 

 may be present only in adult animals and may be more 

 pronounced in males. Younger animals, particularly females, 

 are often stubbier and somewhat barrel-shaped behind the 

 head. In all animals the back is smooth, lacking even a trace of 

 a dorsal fin. 



The head of the bowhead whale is smooth, black, and 

 without the bonnet and the "rock-garden," the colorful 

 clusters of callosities characteristic of the black right whale. 

 The blowholes are widely separated, and the blow emanating 

 from them projects upward as two separate, distinct spouts. 

 Though two separate columns sometimes may be visible 

 under windless conditions in the blows of most mysticetes, 

 this feature is exaggerated and is most characteristic in the 

 bowhead and right whales. 



Bowhead whales are black overall, except for a white 

 "vest" of uneven coloration on the chin. Within that vest, near 

 the sides of the white zone, there may be a series of grayish 

 black to black spots, which on some animals have been likened 

 to a string of beads. The vest is clearly visible when a 

 surfacing animal is viewed from the front or the side or when 

 the animals hang vertically in the water with the head on the 

 surface and the tail flukes down, as they do during periods of 

 early spring mating. 



Natural History Notes 



Bowhead whales are ususally found singly or in groups of 

 up to three animals, though fall concentrations may include 

 up to 50 animals. 



Bowhead whales sometimes breach, throwing most of the 

 body clear of the surface and reentering with a resounding 

 splash. 



May Be Confused With 



Bowhead whales are the only species of large whales 

 found routinely in Arctic waters. Though other species, 

 including some of the balaenopterid whales and the right 

 whale, may venture north as far as the southern limits of the 

 bowhead whale and beyond, they usually do so in the spring 



and summer, at a time when the bowhead whales are farther 

 to the north. Evenif they are encountered together, bowhead 

 whales can be distinguished from all the balaenopterid whales 

 by the absence of a dorsal fin. Bowhead whales have neither a 

 fin nor the slightest trace of a dorsal fin or ridge, while all the 

 balaenopterids have a dorsal fin; and their back is extremely 

 smooth, like that of the right whale. The bowhead and right 

 whales may be readily distinguished from one another by the 

 characters listed below for stranded specimens. 



Distribution 



Though bowhead whales in the western North Atlantic 

 were once distributed from Arctic waters, from the edge of 

 the ice, south as far as the Strait of Belle Isle and the St. 

 Lawrence River in such abundance that they were once 

 referred to simply as "the whale," overwhaling through the 

 19th century until as recently as 1911 has severely reduced 

 their numbers and restricted their modern range. Today in 

 addition to the more abundant populations of the Bering, 

 Beaufort, and Chukchi seas and the Sea of Okhotsk, there are 

 populations off eastern Greenland and in Davis Straits, Baffin 

 Bay, James Bay, and the adjacent waters. Within these 

 ranges, bowhead whales move southward in front of the 

 advancing ice floes and may be expected near the southern 

 limits of their range from September or October through the 

 early spring months. Populations in the western North 

 Atlantic appear to be increasing slowly. 



Stranded Specimens 



In addition to the fact that their ranges may overlap only 

 slightly if at all, bowhead whales may be distinguished from 

 the other right whales of the western North Atlantic by 

 differences in 1) primary distribution, 2) coloration, 3) 

 lengths of the longest baleen plates, and 4) presence of 

 callosities. 



Bowhead Whale 



Right Whale 



DISTRIBUTION 



Arctic distribution south to 

 Davis Straits only during 

 winter. 



Texas, southwest Florida 

 north to Iceland, reaching 

 northern limits only during 

 spring and summer. 



COLORATION 



Black with white "vest" on 

 front part of lower jaw, 

 sometimes containing a 

 string of black spots; upper 

 jaw lacks the "rock garden." 



Sometimes black often 

 brown or mottled with re- 

 gions of white on chin and 

 belly; patches of yellowish to 

 pink callosities and lice 

 encrusting the snout in what 

 has been called a "rock 

 garden." 



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