ESTIMATE OF YOUNG EUR SEALS. 99 



duriug the season. The actual iiuinber represented by this total i>f rejected animals 

 can not be exactly determined. From this it would seem necessary to suppose that 

 by no means all the younger seals appear on the hauling grounds duriug the killing 

 season. In fact the records of the drives show that it is only after the middle of 

 July that the yearlings begin to arrive in numbers. The older bachelors appear 

 earliest, and by the time the killing season is over the great majority of the killable 

 seals are secured, leaving the population of the hauling grounds almost exclusively 

 yearlings and 2yearolds. 



THE 1 AND 2-VEAK-< )LD FEMALES. 



What has been said about the 1 and 2-year-old bachelors applies equally well to 

 the same class of females. These do not appear on the islands before the 1st of 

 August. The 2-year-olds come on the breeding gi-ounds and are scattered about 

 among the harems, spending a few days and leaving. They come and go at intervals 

 during the rest of the season, playing among the pups in company with their yearling 

 sisters. It will never.be possible to enumerate these younger classes of seals. 



THE LOSSES AMONG YOUNG SEALS. 



One element of uncertainty regarding all the younger classes of seals lies in the 

 absence of any definite information regarding the losses they sustain at sea during 

 their early migrations. We know that such loss must be great, but that is all. From 

 all the data at hand it seems certain that not more than one-third of the pups born in 

 any particular year survive to killable or breeding age. This percentage must have 

 been still smaller in the earlier days, when the herd was more crowded and occupied 

 to greater extent the sandy areas. Doubtless, when the herd was at its maximum, in 

 the seventies, not more than one-fourth of the jiups reached the age of 3 years. 



It is fortunate that no vital importance attaches to the exact number of these 

 younger animals. The important matter is the number of breeding animals, and this 

 we have. But it is worth while to construct an estimate of the younger classes, if 

 such a thing can be done, and in the quota of the year 1897 we have a basis for fairly 

 satisfactory results. 



THE ESTIMATE OF NONBEEBDING SEALS. 



During this season a quota in round numbers of 20,000 skins was taken on the 

 Pribilof Islands. This number included some 2-year-olds and some 4-year-olds, but as a 

 rule the animals taken were 3-year-olds. Some 3-year-olds were left over, and some that 

 would have been o-year-olds in 1897 had been killed as 2-year-olds in 18!t(!. We might 

 even the matter up and say that the quota practically represented the norm.al quota 

 of animals of 3 years old. I'.ut as there are elements of uncertainty in the problem, to 

 be on the safe side and for the purposes of argument, we may suppose that there was 

 a maximum of 2.5,000 3-year old males which did or should have survived in 1897 from 

 the birth rate of 1894. An equal number of females survived from the same year. 

 These young breeders, which came upon the rookeries to bear their first pups in 1897, 

 have already been included in the estimate of breeding cows. 



As nearly as we can judge, the total birth rate for the j-ear 1894 was approximately 

 200,000. Of these, under normal conditions, about one-third, or something like 65,000, 



