WHALE HUNTING WITH GUN AND CAMERA 



or on their sides repeatedly striking the surface with the 

 head. When leaping a favorite trick is to throw the body 

 around until the dorsal fin is forward, with a resulting 

 splash that sends the spray quite out on the floor. A high 

 leap by one of them is usually a signal that starts them 

 all to leaping. Our fears that they might leap quite out 

 of the pool were unfounded; they are clever enough to 

 avoid the wall which surrounds them. 



Another game is played by going around the pool with 

 short dives, each time striking the surface with the flat 

 of the tail. When the pool is entirely full of water their 

 play is livelier than when the water level is lowered. The 

 increased depth gives them more confidence and they often 

 turn complete forward and backward somersaults. 



The ordinary swimming motion of the tail is up and 

 down, but, if playfully charged by a companion, the por- 

 poise seems to make a spurt ahead by more or less side 

 action of the tail. This is not easy to determine, however, 

 and may be more apparent than real, as the water is too 

 much disturbed by high speed dashes for accurate ob- 

 servation. The animal undoubtedly relies upon its tail for 

 propulsion, the flippers or pectoral fins being brought into 

 action in making turning movements. Several of the por- 

 poises have lately taken to swimming on their backs, and 

 the movement of the flippers and tail at such times is easily 

 seen contrasted with the white under parts. In swimming 

 on the back, however, there is considerable lateral action 

 of the tail. 



Frequently three or four of them will bunch together in 

 the center of the pool, rolling and rubbing against each 

 other in a ball-like mass suggestive of the tussling of pup- 

 pies. This may at times mean that they are merely scratch- 

 ing, as the single porpoise kept in the Aquarium for two 

 and a half months last summer frequently rubbed his sides 

 or back against the back of a large sturgeon kept in the 

 same pool. This injured porpoise indulged in no play and 



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