Body to 17 m long: males grow significantly larger than females. 

 Body dark grayish-brown to brown; wrmkled in appearance. 

 Back has rounded or triangular hump followed by knuckles along 



spine. 

 Head boxcar-like, comprises up to 40% ot body length. 

 Single blowhole on left of head at front; blow projects forward 



obliquely and to left. 

 Distribution extends from tropics into Bering Sea; adult males 



distributed farther north ( to north ot 40 N ; than females or 



young ( remain south of 40 N ). 

 Flukes straight on rear margin, marked by side V-notch, and raised 



on longer dives. 



Sperm Whale 



Physcur macroccphalus (A) 



Without a Dorsal Fin 



There are three species of large whale without a dorsal fin in the 

 eastern North Pacific and in western Arctic waters. All three are baleen 

 whales. The first two, the right and howhcad whales, have enormous 

 heads and smooth backs without even a trace of a dorsal fin. The third, 

 the gray whale, has a head which is triangular in lateral or dorsal aspect, 

 and a distinct dorsal ridge serrated by 6-12 crenuLitions that give the 

 back a saw-toothed appearance as the animal humps up to begin a dive. 

 All three whales have distinctive blows. In the bowhead and right 

 whales, the projection of the blow upward from two widely separated 



blowholes assumes a very wide V-shape with two distinct columns, 

 which may be seen when an animal is viewed from front or back. 

 Though other baleen whale species may exhibit a V'-shaped spout 

 under ideal conditions, this feature is exaggerated and consistent in the 

 bowhead and right whales and may be used as a primarlv key to their 

 identification. In the gray whale, the low bushy blow assumes in 

 windless conditions what has been described as a "heart-shape". 



The three species can best be distinguished as follows: 



Body to 14 m long usualh' more than 12 m). 



Body mottled gray, may appear uniformK- dark gra\' (in newborn) or 



light gray ( in larger animals ). 

 Head nearly triangular m dorsal and lateral profiles. 

 Head often bears barnacles and many cyamid "whale lice." 

 Line of mouth slightly arched. 



Baleen yellowish-white to white, relatively short (to 'Am long). 

 Blow low ( less than 4 m high) and bushy. 

 6-12 bumps or ridges creating saw-toothed appearance on dorsal 



portion of tail stock. 

 Distribution primarily coastal, from Mexico to Beaufort Sea — 



strongly migratory. 

 Flukes raised on long dives. 



Gray Whale 



Eschnchtius rohuslus (A) 



39 



