26 FUR-SEAL FISHERIES OF ALASKA IN 1910. 



This is the result solely of the method of estimation adopted alike 

 for both years. Both are based upon the number of cows born two 

 years previously. In 1907, 50,825 pups were estimated to have been 

 born, and 10,165 of these were computed to have survived as 2-year- 

 old males in 1909. On the other hand, in 1908, the same method 

 of estimation would indicate that 53,884 pups were born in that 

 year — 3,000 more than in 1907 — and that of these the number sur- 

 viving as 2-year-olds in 1910 was 12,124. 



It is believed that it is not the intention of anyone to claim that an 

 increase in seal life has occurred at any time within the past few 

 years in the face of the large catches of seals in the water, consisting 

 mainly of breeding females. It is believed, on the other hand,-that a 

 marked decrease has occurred, a belief justified when the contracted 

 space occupied by the breeding seals is viewed. But the measure of 

 this decrease is ascertainable solely by estimation, the same methods 

 being used from year to year. When using only a few seals in estab- 

 lishing a basis for computing the whole number, it is not difficult to 

 realize that a few chance harems more or less on the space counted 

 would have the effect of greatly increasing or decreasing the whole 

 number computed to be in the herd. It would be easy to revise these 

 calculations by adding to or subtracting from the estimated number 

 to make it conform with one's idea of what number should or should 

 not be found. But the idea one may have might be more incorrect 

 than the result of the computation, so that in a revision it would 

 not be possible to determine whether in increasing or decreasing the 

 result one were moving in the direction of accuracy or away from it. 

 It is much better to announce the number each year as it may 

 appear from calculations made similarly, and to explain any apparent 

 incongruity by the statement that the whole is an estimate and 

 nothing else. 



The result of the killing of 1910 has demonstrated that the number 

 of 2-year-old bachelors estimated as remaining in the herd at the 

 close of the season of 1909 was entirely too small. In the census of 

 1909 only 2,165 2-year-old bachelors were allowed. These of course 

 would be 3-year-olds in 1910. As a matter of fact, the skins of 1910 

 when classified in London showed that perhaps 5,000 of the catch were 

 3-year-olds. In view of this fact it is believed that, in estimating 

 the number of these as well as other immature seals, a smaller death 

 rate should be allowed than hitherto. 



PUP-RAISING EXPERIMENTS. 



In accordance with the Bureau's instructions, attempts were made 

 on both St. Paul and St. George Islands to feed starving pups and save 

 their lives. On St. Paul Island the efforts were unsuccessful, but the 

 St. George experiments yielded most interesting results. 



