THE RE-ENTRANTS 



319 



aoTTLE-NOSCO DOUPHIN 



KILLER WHALE 



Fig. 194. Porfoises and dolphins. 



Hahits: This is the best known dolphin, both to swimmers and to inshore 

 seafarers. It is the only dolphin commonly seen in river mouths, bays, and beach 

 areas of the Atlantic Coast. It is less common on the Pacific Coast, perhaps 

 because the waters are colder there. 



The favorite food of the dolphin is mullet, which it pursues by sight. It also 

 has been observed to dash into a school of these fishes and send one aloft with 

 a stroke of its tail. The mullet then falls into the dolphin's awaiting jaws. 



Dolphins travel with great ease through the water and are among the fastest 

 of swimmers, capable of playing about ships' bows at 40 mph or a little over. 

 They breathe at the surface every ten to sixty seconds and are capable of a 

 six-minute submersion. Surprisingly enough, they drown rather easily if water 

 gets in the blowhole. 



These are not only very speedy swimmers, but they are also very active 

 ones. Their mammalian warm-bloodedness and efficient circulation accounts for 

 this. Swimming in water takes great amounts of energy, so it is not surprising 

 to find that the blood of dolphins can hold much more oxygen than that of land 

 animals of equal size. Their sense of hearing is acute. They utter whistles, barks, 

 and clucks through the blowhole and communicate by these means. They also 

 whimper when injured. 



Dolphins are much-fabled animals, long held in high esteem by sailors. This 

 is not without reason, for dolphins are the known enemies of sharks. It is a bit 

 hard to separate fact from fancy on this score, but dolphins have been reliably 

 reported to attack both hammerhead and tiger sharks in the sea and in captivity. 

 They harass sharks by punching them with their hard, bony snouts in a series 



