173 



KEY TO MARINE MAMMALS (Cont.) 



32' Adults spotted, but young (1 m in length) are not (shale-blue all 



over); no teeth in lower jaw, but one pair in upper jaw, usually not 



showing in females; in males and sometimes females one or both of 



these teeth may grow into a tusk up to 3 m in length. NARWHAL 



33 No dorsal fin; color very dark except for thin white stripe on belly 

 that widens between flippers to form a large patch; tip of lower jaw 



and ventral side of flukes usually white. , NORTHERN RIGHT WHALE DOLPHIN 



33' Dorsal fin present; color not as in 33. 34 



34 Tooth crowns flattened, oval in cross section, usually more than 2.5- 

 2.8 cm in diameter (in the middle of the jaw); an ovate white 



spot on side of the head, but if absent, then dorsal fin distinctly 

 higher than long; a white band on middle of the abdomen, with a 

 branch directed to the rear on each side of the anal region; flippers 

 ovate (less than twice as long as wide). KILLER WHALE 



34' Tooth crowns more or less round in cross section near the gum, not 

 more than 2.5-2.8 cm in diameter; no ovate spot on the temple; dorsal 

 fin not distinctly higher than long; coloration of the abdomen 

 different than in 34; total body length less than 4 m, OR if 

 longer (4-6.5 m), then flippers pointed and long (length of flippers 

 more than 2.5 times the width). 35 



35 No teeth, or rarely 1-2 pairs of teeth, in upper jaws; 2-7 pairs 

 of teeth in the anterior part of the lower jaw; forehead almost 

 vertical, with a central longitudinal crease. RISSO'S DOLPHIN 



35' More than 6 pairs of teeth each in upper and lower jaws; forehead 

 usually rising gradually from snout, but if steep then no crease in 

 forehead. 36 



36 Head rounded, beakless, the forehead rising almost vertically from 

 snout; not more than 8-13 pairs of teeth in each jaw; total length 

 6.5 m. 



36' Beak well defined, or if absent, the forehead low, not rising ver- 

 tically from the snout; more than 15 pairs of teeth in each jaw; 

 total length up to 4 m. 38 



