PUR-SEAL CENSUS, PRIBILOF ISLANDS, 1917. 109 



The Average Harem in the Years 1912-1917, Inclusive — Continued. 



Derived from estimates. 



Some rookeries, which in the earher years had averages which ap- 

 proximated the whole, later made considerable deviations there- 

 from. And the converse is true. No area can be said to constantly 

 contain the average development of the herd in a single phase. But 

 no other method is known whereby as accurate an estimate can be 

 obtained as by the average harem method. Small rookeries, how- 

 ever, should not be considered in any deductions of this sort because 

 they are erratic in development and growth and are subject to much 

 greater variations than the larger ones. 



Average Harem and Percentage of Idle Bulls to Harem Bulls, 1916 and 1917. 



Rookery. 



ST, PAUL ISLAND. 



Kitovi 



Lukanin 



Gorbatch.... 



Ardiguen 



Reef 



Sivutch 



Lagoon 



Tolstoi 



Suthetunga. 



Little Zapadni.. 

 Zapadni Reef.... 



Polovina 



Polovina Cliffs.. 

 Little Polovina. 



Morjovi 



Vostochni 



Total. 



ST. GEOEGE ISLAND. 



North 



Staraya Artil. 



Zapadni 



South 



East Reef.... 

 East Cliffs.... 



Total. 



Total, both is- 

 lands 



Breed- 

 ing cows. 



2,472 

 2,141 

 8,864 

 700 

 16,331 

 5,020 

 388 

 12,065 



6,277 



266 



4,744 



1^074 

 2,761 

 24,387 



98,855 



6,246 

 5,545 

 965 

 19 

 1,585 

 3,762 



Harem 

 bulls. 



Average 

 harem. 



26.0 

 33.4 

 37.9 

 21.2 

 33.3 

 31.0 

 29.8 

 33.4 



31.3 

 35.3 

 33.2 

 29.3 

 28.5 

 34.6 

 29.1 

 37.3 



31.2 



3l'.l 

 6.3 

 21.7 

 36.5 



Percent- 

 age idle 

 bulls to 

 harem 

 bulls. 



70.3 

 47.0 

 27.3 

 54.9 



61.5 



107.4 

 88.2 

 12.5 

 55.5 

 79.7 

 67.7 

 92.6 

 93.4 



77.27 



51.5 



76.8 

 151.6 



500 33.42 75.20 128,024 



Breed- 

 ing cows. 



o 2,520 



2,235 



o8,649 



726 



17,442 



5,060 



466 



o 15,433 



9,828 



o 6,863 



358 



4,918 



1,761 



1,260 



o 2,921 



128,249 



: 6,783 

 5,642 

 1,050 

 24 

 1,786 

 4,050 



19,335 



Harem 

 bulls. 



126 

 100 

 279 



33 

 613 

 184 



24 

 671 

 2 

 420 

 259 



22 

 166 



87 



35 



127 



1,018 



20.0 

 22.3 

 31.0 

 22.0 

 28.4 

 27.5 

 19.4 

 23.0 



23.4 

 26.4 

 16.2 

 29.6 

 20.2 

 36.0 

 23.0 

 27.7 



25.5 

 34.6 

 31.8 

 4.0 

 22.0 

 30,0 



.26 



Percent- 

 age idle 

 bulls to 

 harem 

 bulls. 



44.4 

 54.0 

 46.5 

 84.8 

 38.6 



62! 5 

 26.8 

 3,200.0 

 8L4 

 27.0 

 59.0 

 78.3 

 35.6 

 145.7 

 65.3 

 77.0 



56.19 



42.8 

 69.3 

 51.5 

 100.0 

 66.6 

 45.1 



53.36 



55.79 



• Based on estimated number of pups. 



