b. No conspicuous grooves present on throat; definite median 

 notch on rear margin of flukes; teeth present [5] 

 Go to 17 



1 J . a. One or two pairs of teeth at or near tip of lower jaw (erupted onh' 

 m some adults :. Read note below, then Go to 14 



b. One pair of teeth well behind tip of lower jaw (erupted only in 

 adult malesy. Read note below, then Go to 16 



Note; Individuals, especially juveniles and adult females, of the species 

 covered in paragraphs 14. 15 and 16 may not be readily identifiable 

 without museum preparation and examination by an expert. 



14. a. Tv\'o pairs of teeth in lower jaw. one pair exposed outside the 



closed mouth at tip ot beak, second smaller pair situated behind 

 the first (teeth erupt late in life for both sexes); body length to 

 12.8m; long, tube-like snout; steep forehead. 



* Baird's Beaked Whale, Bcrardius hairdii (A) 



b. One pair of teeth at tip ot lower jaw (exposed only in adult 

 males) Go to 15 



15. a. Beak distinct, elongated; pronounced bulge to forehead; occa- 



sionally a second smaller pair of teeth behind primary pair at 

 apex of mandible; maximum body length to about 9 m: north 

 Pacific distribution — tropical. 



* (Southern) Bottlenose Whale. Hypenodon planifrom (T) 



b. Beak not distinct or elongated; head small relative to body size; 

 forehead scooped (slightly concave) in front of blowhole, in- 

 creasing in concavity' with increasing size; m profile back in- 

 dented behind blowhole; single pair of teeth at tip; united 

 portion of lower jaw [6] less than one-fourth the length of entire 

 lower jaw; mouth line upturned at gape; body coloration lighter 

 on head, grading to all white; body length to 7.0 m; distribution 

 from south Bering Sea to Equator. 



* Cuvier's Beaked Whale, Ziphius cavirosiris (B) 



16. a. Moderate beak not sharply demarcated from forehead; males 



with white convexity (a "cap" or "beanie") in front of blowhole, 

 and white anterior half of beak; females and young with light 

 front half of lower jaw; males with lari;e flattened tusk rooted in 

 each side of lower jaw, protruding outside closed mouth; 

 mouthline of females and young curved as m males but teeth 

 uncrupted; maximum body length less than 6 m. Females and 

 young require museum preparation for positive identification. 

 Cold temperate distribution. [7] 



* Hubbs' Beaked Whale, Misoplodon carlhuhhsi (B) 



[5] Narwals litem i^.c. i and older Risso's dolphins (item 25.a.) may 

 lack teeth. 



[6] By feeling the lov\'er jaws on the lentral surface and moving the 

 finger towards the tip of the snout, one can feel the point at which the 

 two lower jaws become united (called the symphysis). This location is 

 an important reference point in distinguishing among some species of 

 beaked whales. 



[7] Due to the subtlety and complexity' of beaked whale systematics, 

 non-specialists are discouraged from making more than generic dis- 

 tinctions for the Mesoplodon group. Photographs are helpful, but for 

 females and young, as well as adult males in some cases, specimen 

 material is essential for reliable species identification. Please ensure 

 that carefully recorded notes, photos and specimen materials reach 

 such a specialist. 



57 



