THE SOUTHERN SEA LION 



TABLE XIII 

 Immature death rates per cent 



159 



Since the herd is assumed to be in a state of equilibrium the stock of bulls before 

 killing was 69,047 and the annual accessions, 16-66 per cent (p. 158), number 11,508. 

 The numbers of the annual killing are known from returns except for 1936, so that the 

 maximum figure under the licence, 10,000, has been used. As shown in Table XIV by 

 making the appropriate additions and subtractions the number of bulls in 1937 is 

 estimated to be 50,895. 



Table XIV 



Stock of bulls 



Immature seal. The 11,508 males needed to maintain the untouched herd of 1937 

 will have been derived from the male pups of 193 1, namely, 40,277, with deaths amount- 

 ing to 28,774 or 71 -44 per cent of the pups born. Of these 1 1,510 are assumed to have died 

 in their first year, and the remaining 17,26410 have died at the rates set out in Table XI II. 

 Since the supply of pups under the present estimate is constant, the number of im- 

 mature seal of any age is easily found. The immature males under estimate A amount 



to 86,471. 



The 80,555 cows require, to maintain their numbers, an annual accession of one- 

 seventh, that is 11,51 1, which, being derived from 40,277 female pups, entails the deaths 

 of 28,766 immature females, namely 71-42 per cent. The deaths in the first year will be 



