318 UNDERWATER GUIDE TO MARINE LIFE 



SPERM WHALES: Family Physeteridae 



There are only two species, one of which, the pigmy sperm whale, is small 

 and rare. The name "sperm whale" refers to the large reservoir of oil or spermaceti 

 that is found on the top of the head, giving it a squarish appearance. 



SPERM WHALE (cachelot) : Physeter catodon 



Size: Males reach up to 85 feet, but usually not over 60 feet. Females reach 

 up to one-half this length. 



Distribution: Tropics to subarctic waters of all seas. 



Identification: The shape of the huge head with the narrow, toothed lower 

 jaw is distinctive. The spout is low and directed forward. 



Hahits: This is Melville's "Moby Dick." The sperm whale is able to sound to 

 great depths (to half a mile or more) and can stay under for as long as an hour 

 to hunt for its food, the giant squid. Scars of squid suckers and tentacle hooks 

 are to be found on its body, mostly about the head. The physiological strain of 

 such prolonged deep dives is tremendous and how the whale stands it is not 

 known. Formerly this whale traveled in large schools of a hundred or more, 

 mostly composed of cows and calves, with a few bulls. Now they are much rarer 

 and schools of fifteen to twenty are large. This is a swift whale, able to attain 

 12 knots. The sperm whale has no enemies except man. Even the killer whale 

 cannot attack it successfully. There is a report of a small group of killers attacking 

 a large sperm whale while the latter was basking on the surface. It soon woke 

 and maimed one of the killers in its jaws and was last seen pursuing the others, 

 which it probably could not catch. 



Ambergris, the valuable perfume base, is taken from the intestine of this 

 whale. Sometimes it is found cast up on coasts. One mass weighing 924 pounds 

 was found cast up on an Australian beach and was valued at $120,000. Usually 

 the pieces found in whales weigh only a few ounces. This valuable animal is 

 being hunted at the present day, and it is a question how long it can stand 

 hunting pressure. It seems to be holding its own, but not increasing. 



PORPOISES AND DOLPHINS: Family Delphinidae 



There are many species of these interesting, very intelligent, small cetaceans. 

 (We must refer the reader to the Bibliography for all but three of them.) Many 

 species are quite rare and are of great zoological interest. Observations of them 

 in the sea would be of value. The term "dolphin" and "porpoise" are commonly 

 used interchangeably. "Dolphin" is also the name of a fish, Coryphaena. As used 

 here, however, it only includes the small, beaked members of this family. 

 "Porpoise" refers to the small beakless species. The larger species are known 

 by various other names and include the narwhal, beluga, grampus, blackfish, 

 beaked whales, and killer whales. Most of these are rare or of northern seas, and 

 some are not strictly of this family. All are very swift, agile, and active carnivores, 

 mostly on lish. 



bottle-nosed dolphin: Tursio-ps tnmcatiis 



Size: Reaches almost 12 feet, but 9 feet is large. 

 Distribution: Cosmopolitan in warm seas. 



Identification: The color is a slaty, dark, bluish-gray. The beak is short, and 

 there is a high forehead. 



