TRUES BEAKED WHALE (T) 



Mesoplodon mirus True 1913 



Other Common Names 



None known. 



Description 



True's beaked whales reach a length of at least 16 feet (4.9 

 m) long. They are chunky in midbody and narrow rapidly 

 towards the tail, closely resembling goosebeaked whales 

 (p. 70). In overall body shape, the head is small with a slight 

 indentation in the area of the blowhole, a slight bulge to the 

 forehead, and a pronounced beak. The flippers are small 

 (from one-fourteenth to one-tenth the body length). The 

 dorsal fin is small, slightly falcate, located in the latter third 

 of the back, and followed by a pronounced ridge on the tail 

 stock. The flukes, which sometimes contain a very slight 

 notch, are broad (to almost one- fifth the body length). 



True's beaked whales are dull black to dark gray on the 

 back, lighter slate gray on the sides, and white on the belly. 

 The body is frequently covered with light colored spots or 

 splotches and bears numerous pairs of scratch marks, 

 presumably tooth rakes (Fig. 76). 



The flippers are all black and are attached in the dark col- 

 oration of the animal's side. The flukes are dark above and 

 below. 



May Be Confused With 



True's beaked whales are most likely to be confused with 

 goosebeaked whales (p. 70) but may also be confused with 

 any of the other beaked whales species (p. 74 and Fig. 78). 



Distribution 



True's beaked whales appear to be primarily temperate in 

 distribution. They have been reported from Cape Breton 

 Island, Nova Scotia south as far as Flagler Beach in Florida. 

 Northernmost records are for summer months. 



The range of True's beaked whales overlaps with that of 

 the Antillean beaked whale but is more northerly. 



Stranded Specimens 



The teeth of adult male True's beaked whales may be 

 visible near the tip of the lower jaw, a characteristic shared 

 with the goosebeaked whale (p. 70) and the northern 

 bottlenosed whale (p. 67). Both these other species reach 

 substantially greater maximum lengths than True's beaked 

 whales, however, and should be readily distinguishable by 

 this and the number of other highly distinctive characteristics 

 of each species. 



Females and subadult males may be confused with any of 

 the beaked whales species (p. 74 and Fig. 78). 



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Figure 79. -Two views of the body of a stranded True's beaked whale from 

 northeastern Florida. This species reaches at least 16 feet (4.9 m) and closely 

 resembles the goosebeaked whale in general body shape. It is distributed in 

 temperate waters from Nova Scotia to Florida. (Photos courtesy of Marineland of 

 FUyrida.) 



77 



