FUR-SEAL CENSUS, PRIBILOF ISLANDS, 1^25 



By Edward C. Johnston 



The annual enumeration of the animals composing the fur-seal 

 herd of the Pribilof Islands was made at the height of the season. 

 An actual count was made of the harem and idle bulls on St. Paul 

 Island on July 16 to 18, inclusive, and on St. George Island on July 

 22 and 23. It was planned to count on St. George Island on July 20 

 and 21, but transportation was not available until July 21, when the 

 United States fisheries schooner Eider carried the enumerator to St. 

 George Island. 



In the spring of 1925, before the seals arrived at the islands, all 

 counting towers were inspected and repaired where necessary. 

 The only tower seriously damaged was that on Staraya Artil rookery 

 on St. George Island. Together with the runway, it had been 

 blown down in the previous winter. Rookery numbers were repainted 

 on St. Paul Island, with the exception of a few that could not be 

 located. Most of those not located were situated on the edges of 

 cliffs or caving banks, and probably were destroyed by the action of 

 the sea. The rookery numbers on St. George Island were repainted 

 in 1924. 



BULLS 



On account of stormy weather during the period when the bulls 

 were counted, it was impossible to reach Sea Lion rock, where 

 Sivutch Rookery is located. It was necessary therefore to estimate 

 the number on that rookery. On all other rookeries of both islands 

 the harem and idle bulls were counted. 



In 1923, 5,012 three-year-old male seals were branded with a hot 

 iron. By watching these branded animals, it will be possible to 

 determine when they become harem bulls. In 1924, none was 

 found on the breeding areas, and in 1925 one 5-year-old bull, not 

 branded, was seen holding a cow. Upon discovering the enumerator, 

 however, bull and cow took to the water. Another observer reported 

 having seen two branded 5-year-olds on St. Paul Island, each 

 attempting to hold a cow. Both took to the water shortly after being 

 seen. Taking into account the small number of breeding bulls, it is 

 fairly conclusive that 5-year-olds can noKyet be classed as breeding 

 bulls. 



In 1924, one bull, estimated to be 6 years old, was seen holding 

 three or four cows. In 1925, seven bulls, probably 6 years old, were 

 found with small harems. Apparently very few 6-year-old bulls 

 can be classed as breeding bulls. 



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