- Body to at least 17.5 feet (5.3 m) long.
- Body black with indistinct light gray area on chest; saddle behind dorsal fin.
- Head becoming more bulbous with age; square in large adult males viewed from above.
- Flippers relatively short (to less than one-sixth of body length).
- Dorsal fin broad-based, falcate to flaglike, in front half of back.
- Distribution tropical and warm temperate; from about Hatteras south.
- Flukes not usually raised on dive.
Grampus
Grampus griseus
p. [96]
- Body to at least 13 feet (4.0 m) long.
- Body of newborn light gray; darkens with age.
- Body of adults light gray or white; scarred with numerous scratches.
- Head blunted, not beaked.
- Forehead has vertical crease in center.
- Dorsal fin less than 15 inches (38.1 cm), rather erect and distinct, and dark even in light adults.
- Distribution tropical to temperate.
- Rarely ride bow wave.
(13-16 feet [4-5 m] maximum overall length)
Without a Dorsal Fin
The only two species of medium-sized cetaceans in the western North Atlantic which have no dorsal fin, the Beluga or white whale and the Narwhal, share such limited common range, well outside the theater of normal boating traffic, that they are generally infrequently encountered.
Both species are easily identifiable when seen.
Beluga
Delphinapterus leucas
p. [99]
- Body to 16 feet (4.9 m) long.
- Body of adults all white; young slate gray.
- Small row of bumps along back ridge near midpoint, sometimes dark brown.
- Distribution usually near coast from Arctic waters to St. Lawrence Gulf and into Hudson Bay.