312 THE WEALTH OF THE SEA 



new-born pup is jet black in color and weighs about 

 ten pounds. At first the mother is careful to keep 

 her pup out of the way of the fighting bulls ; but as 

 the pup grows older she pays much less attention to 

 it, allowing it to shift for itself for the most part. 



When the pups are about six weeks old, they learn 

 to swim, and as the summer progresses they swim 

 farther and farther out; in October they swim in 

 schools completely around the islands. But they 

 always return to the rookery to nurse their mothers. 

 Seal milk must be very rich, for, although the pups 

 eat nothing else, they grow very fast, gaining about 

 ten pounds a month. By the first of October, their 

 color has changed to a glistening silvery gray, and 

 in November they go south through the Aleutian 

 passes, from which they do not return until the 

 middle of the following August. 



The mature cows are not much larger than four- 

 months-old pups, for they weigh only from fifty to 

 a hundred pounds. The bulls are very much larger 

 than the cows, weighing four or five hundred pounds. 

 They are usually of a rusty red color and have a 

 bristly mane about two inches long on the back of 

 the neck. The bulls are very ferocious and do hot 

 permit intruders on the rookeries until the height 

 of the breeding season is past. Much quarreling 

 takes place between neighboring bulls on the breed- 

 ing grounds, and occasionally a pair fights until the 

 loser gives up his place and goes to sea. 



The seals on the Pribilof Islands are carefully pro- 

 tected by the United States government. A special 



