10 



ALASKA FUR-SEAL ROOKERIES, 1910. 



Then, again, on the other rookeries an increase or decrease in the 

 number of active males produces a corresponding rise or fall in the 

 estimated number of cows. For example, on Vostochni there may 

 be 6,500 cows and 200 active bulls. If 20 idle bulls, before the height 

 of the season, secure 1 cow apiece, they enter the active list, and 

 there are then 220 harems. As the average harem is 31.7, this 

 increase affects the estimate to the extent of a gain of 634* cows, 

 though in reality the number of cows has remained constant. At 

 present this gain or loss in the active bull list outside of Kitovi is of 

 relative unimportance, but it is conceivable that under certain cir- 

 cumstances it may assume a more prominent role. 



I have in mind the fact that in treating this phase of the problem 

 we are, after all, dealing in generalities, but the results may become 

 so general that they have little actual value. In my opinion it is 

 highly desirable that a pup count on all of the rookeries be made 

 during August, or even early in September, in stress of weather, or 

 possibly after the sealing fleet has left Bering Sea; and again a 

 similar survey should be made five years later, when the typical 

 rookery could be determined and questions relating to the increase 

 or decrease of the herd be settled beyond a reasonable doubt. 



ESTIMATES OF COWS AND PUPS. 



Assuming that the average harem comprises 31.7 cows, the total 

 number in the entire seal herd is computed in the following table: 



Computation op Cows and Pups on St. Paul and St. George Islands, 1897, 



1909, and 1910. 



Rookery. 



St. Paul Island: 



Gorbatch 



Ardiguen 



Reef 



Sea Lion Rock. 



Kitovi 



Lukanin 



Polovina 



Polo vina Cliffs . 

 Little Polovina 



Morjovi 



Zapadni 



Vostochni 



Little Zapadni. 

 Zapadni Reef... 

 Tolstoi 



Rookery. 



Si. 



St. 



Paul Island — Contd. 



Tolstoi Cliffs 



Lagoon 



Total 



George Island: 



Little East 



East 



Zapadni 



Starava Artel 



North 



Total 



Grand total 



1897 



2,891 

 2,598 



1,190 

 3,776 

 3,923 

 1,681 

 5,782 



16.342 



128, 365 



1,452 

 693 



11,266 



144 

 2,340 

 1,548 

 1,512 

 3,816 



9,360 



50,626 



35.502 



127 

 1,870 

 1,490 

 1,522 

 3,266 



8,275 



43,777 



a Estimates of Mr. George A. Clark. 



6 Estimated. 



In the above census it is to be remembered that the totals apply 

 to cows and pups and that both together number 87,554 in 1910. 



