102 MAMMALS OF THE PACIFIC WORLD 



up the Atlantic coast to the mouth of the Rio de la Plata. Seen 

 at a distance, the sea lions seem to be colored uniform brown. 

 The prominent manes are lighter in hue. Males, which have 

 short faces and pug noses, may reach a length of nine feet; 

 females are smaller. 



The fur seals or sea bears differ from the sea lions chiefly 

 because of their thick underfur and longer and luxuriant outer 

 hair. The coat of a sea lion is short and lacks the underfur. 



The Northern Fur Seal (Callorhinus alascanus), the animal 

 from which seal-skin coats are made, is the best known of the 

 fur seals. This animal's breeding ground is the Pribilof Islands 

 in the Bering Sea, but in winter it migrates south as far as 

 California and Japan. On account of the value of its fur the 

 northern fur seal was rapidly becoming extinct, but following 

 the purchase of Alaska, the United States government, after 

 extensive research, protected the breeding colonies and con- 

 trolled the killing of these animals. At the present time special 

 government agents supervise the killing, and allow only young 

 male seals three and fours years old to be killed. The number 

 of fur seals is again increasing. 



An adult male or bull is very dark brown, with grayish hairs 

 on the shoulders. It is about six feet long and may weigh as 

 much as five hundred pounds. The paler females are grayish 

 brown and weigh only about one hundred pounds. The breeding 

 of the northern fur seal is of special interest. Old males arrive 

 on the breeding grounds on the Pribilof Islands in early May. 

 They are in fat, healthy condition, and are at least six years 

 of age. They fight among themselves, as each bull seeks to es- 

 tablish a small section or "station" on the coast as its own. 

 About the middle of June the females or cows come ashore at 

 the stations lorded over by the bulls. The number of females 

 in each harem varies greatly ; from twelve to fifteen, or as many 

 as a hundred have been recorded. Soon after the females ar- 

 rive the pups of the previous season's mating are born, gen- 

 erally one to each female. The main rutting season is in July. 



