ALASKA FUR-SEAL ROOKERIES, 1910. 11 



YEARLINGS AND 2-YEAR-OLDS. 



Of the various computations necessary to arrive at an estimate of 

 the entire seal herd those concerned with the 2-year-olds and year- 

 lings are the least satisfactory. And yet by restricting the quota of 

 skins taken to 3-year-olds we could in a relatively short period arrive 

 at a fairly close approximation, and at the same time settle other 

 vexed questions that are in need of solution. At the present time 

 we are compelled to base our estimates largely on the quota and those 

 males dismissed from the killing grounds. 



In the quota this year 10,210 skins weighed less than 7 pounds 

 each, and 2,603 males were dismissed from the drives because they 

 were undersized. Some of the latter were doubtless driven more than 

 once, but even so it is probable that the number was not less than 

 1,800. Besides these, 337 2-year-olds were branded early in the 

 season. This accounts for 12,347. That there are yet others is evi- 

 denced by the fact that fully 700 bachelors of killable size appeared 

 on the hauling grounds of both islands in early August after the 

 killing season, in addition to which there were probably other young 

 animals in considerable numbers, though how many is uncertain. 

 And it is probable, also, that some were at sea, but here again we have 

 no exact information. A conservative estimate of 2-year-old males 

 is therefore 13,000, which is also the number of virgin 2-year-old 

 females that during the late summer arrived at the rookeries. 



It appears to be the general belief that in 1909 there -were 12,000 

 yearlings of each sex, and judging from estimates based on , pup 

 counts and the quota, the herd appears to have been stationary for 

 the past three or four years. Hence we might suppose that the num- 

 ber of yearlings for this year is approximately the same as last. 

 However, it is possible that the estimates based largely on Kitovi are 

 misleading and that the quota was maintained by closer and closer 

 killing. Future observations alone will settle this question. In 

 order to be on the safe side we may assume that a shrinkage of 10 

 per cent has taken place and that accordingly the number of year- 

 lings of each sex for the year 1910 is 10,S00. 



THE RESERVE. 



For six years prior to 1910 two thousand 2 and 3 year old males 

 were reserved annually, but as the brand, made by clipping the hair 

 on the head, was not permanent, we have no means of knowing how 

 many of these were subsequently killed. If 1,000 were actually 

 exempted each year and there is an annual mortality of 10 per cent 

 there should be between 500 and 600 this year remaining of the 

 reserve of 1905. And if the decline of the present number of active 

 bulls is approximately 300 there should this year be an increase of 



