THE SOUTHERN SEA LION 



'57 



The presence of the letter "e" after a number signifies that it is estimated. 



Nos. 65 to 68 are unimportant rookeries in which the numbers were not estimated. 



ESTIMATES OF THE TOTAL HERD 



The season of the count of the last section, 1937, has been chosen for estimates of the 

 entire herd, and two are presented. A, with the assumption that the herd has already- 

 attained its maximum size and is now in a state of equilibrium, and B, with the assump- 

 tion that the numbers are increasing. 



In arriving at the final figures account has been taken only of the dead pups actually 

 found. They amounted to 0-56 per cent of the total, but I have little doubt that the 

 number was too low. Pups are fragile creatures and when dead might easily be destroyed, 

 and it was hardly ever possible to search the ground so closely as to ensure that all dead 

 pups had been found. In one small rookery 5-6 per cent dead pups were counted, but 

 since the total there was less than 300 I have refrained from applying to the whole herd 

 a correction of this magnitude which would entail an addition of 45 1 1 to the count. 

 Moreover, it is quite possible that the infantile death rate varies from one rookery to 

 another, as it does with the Northern Fur Seal (o-8 to 2-8 per cent). 



It has been quite impossible- to form any estimate of the number of the mature but 



