NARWHAL (T) 



Monodonmonoceros Linnaeus 1758 



Other Common Names 



Unicorn whale (historical name not currently in use). 



Description 



The narwhal, also known as the unicorn whale because of 

 the long tusk found on adult males, is one of two 

 medium- sized whales found in the Arctic waters of the 

 northwestern Atlantic. They reach a maximum length of 

 from 15 to 16 feet (4.6 to 4.9 m) excluding the tusk. Newborn 

 calves are approximately 5 feet (1.5 m) long. Narwhals have 

 small rounded heads and a small mouth. Like the other 

 medium-sized whale in the same region, the beluga or white 

 whale, the narwhal has no dorsal fin. Instead, it has a series of 

 bumps, approximately 2 inches (5.1 cm) high along the 

 midline of the back in the half nearest the tail. The ridge 

 created by these bumps may be readily seen on a swimming 

 animal. 



The basic coloration of the species changes slightly with 

 age. Young animals are uniformly dark bluish gray on the 



back but rapidly begin to develop the numerous leopardlike 

 spots on the back and sides characteristic of adults. Those 

 spots rarely extend onto the belly even in old animals. 



Narwhals have only two teeth. In the females, these teeth 

 rarely emerge from the gums. In males, one and sometimes 

 both of those teeth grow out the front of the snout, spiraling 

 in a left-hand or sinistral direction, and may reach a length 

 of 9 feet (2.7 m). One or two tusks may also be exposed, 

 however, in females. 



Natural History Notes 



The function of the tusk in male narwhals is unknown, but 

 it was this feature of the animal that earned it the name 

 "unicorn whale" and resulted in its extensive hunting by 

 whalers. During their annual migrations narwhals may 

 congregate but are commonly found in groups of 10 or fewer 

 during the rest of the year. 



Narwhals feed on a variety of organisms, including cod, 

 rockfish, flounder, and crabs, but their diet consists primarily 

 of squid. 



'^\*^ 



-^ •awmii 



Figure 1 12. - In this photo of narwhals, the origin of the name "unicorn whale" is apparent. The animal at the right, an adult male, exposes his tusk 

 as he surfaces aggressively to breathe. Even when this feature is not observed, however, the narwhals' mottled gray coloration makes them easy to 

 distinguish from the all-white belugas, with which they share a common range. Note also the dorsal ridge on the animal to the left. {Photo by D. 

 Lusby, courtesy of the Sea Library. ) 



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