Tailflukes extended for deep dive. Courtesy Scripps Institute of Oceanography.
Whale Types
Porpoises and Dolphins
Whales are known technically as cetaceans (pronounced seh-TAY-shuns); so also are the various porpoises and dolphins which are mostly eaters of fish. These are certainly the most numerous of all the cetaceans, making up in numbers for their small size (6 to 8 feet). A few species range between 20 and 30 feet. Porpoises and dolphins congregate around schools of fish. Therefore fishermen are constantly on the lookout for a sight of them. Since not infrequently the porpoises break the surface of the water, leaping completely clear as if for a look around, they are not difficult to locate. Porpoises and dolphins can be seen most frequently in coastal waters where fish are most abundant. The porpoise and dolphin families contain a great many species and it is beyond the scope of this treatise to differentiate or name them all. However, these families include such unique forms as the killer whale, narwhal, white whale (or beluga as it is known to the Eskimos), and the pilot or black whale. Generally one associates cetaceans with the ocean, so it may come as a surprise to find that four dolphin species live in such major rivers as the Amazon, La Plata, Ganges, and the Yangtze.
In dolphins, the mouth protrudes beyond the head as a beak or snout, and in porpoises, the front of the head is blunt or gently rounded. It is impossible to avoid confusion if one uses common names to separate the various whales. Even though the word whale properly covers all the kinds, to some it connotes only the larger species. Such a distinction is wholly arbitrary, and cannot properly differentiate the natural groupings of whales to which zoologists have assigned technical names. It would be impossible to summarize the variety of common names which many of the species have acquired through the centuries. The only solution to this is to refer to the whales by the technical names which connote relationship. (For readers who desire this differentiation, a brief listing of the groups and representatives of each are provided in an [appendix].)
BALEEN WHALES
BLUE WHALE (SULPHUR-BOTTOM WHALE) FIN-BACK WHALE (COMMON RORQUAL) GREENLAND RIGHT WHALE (BOWHEAD WHALE) BLACK RIGHT WHALE SEI WHALE HUMP-BACKED WHALE (unlabelled in picture) CALIFORNIA GRAY WHALE LITTLE PIKED WHALE (LESSER RORQUAL) PYGMY RIGHT WHALE The Sperm Whale is given here for size comparison only.
TOOTHED WHALES