THE STOCK OF WHALES AT SOUTH GEORGIA 



Table V 



Female Fin zvhales. Estimated age composition of the 

 observed catch in season 1929-30 



371 



The greatest damage inflicted on the population now appears to be spread over the 

 period between the second and seventh year of life. There is, however, another way in 

 which these results bear upon the question of depopulation. If it be allowed that 

 sexually mature females produce a calf every two years and that every other calf is 

 female, then in the distribution of the population shown in Table V the increment 

 per two years of female calves more than one and less than three years from birth 

 would be one quarter of the mature females, i.e. 47. But the rate of destruction is 

 shown to be 62, so that on this evidence, in so far as Table V is representative of 

 the stock, severe damage is being done. Shortage of old whales does not appear to 

 have been a feature of season 1929-30, but the absence of lactating and resting whales 

 is quite strongly marked. The numbers taken are too small to respond satisfactorily to 

 mathematical treatment, and indeed, the figures that have been used in computing the 

 rate of reduction must not be accepted too literally. Apart from the errors introduced 

 by taking five seasons together there are probably more serious faults, due to the over- 

 lapping of the age groups, which are impossible to estimate. The conclusions must 

 therefore be regarded as indicative of the state of affairs only. 



The crux of the problem is the identity of the whales visiting the area in successive 



