286 DISCOVERY REPORTS 



understood when the data on ovaries have been worked out. In the meantime it can be 

 said that it is better to kill a large or old whale than a small or young whale because a 

 better yield is obtained from a large whale, and because a young whale will have contri- 

 buted little or nothing to the stock in reproducing itself. 



(iv) Adult females may be pregnant, lactating or resting. Existing regulations pro- 

 hibit the killing of a lactating female (i.e. one nursing a calf) because it is presumed that 

 the calf cannot survive without the mother, and two whales are thus killed for the pro- 

 ducts of one. The killing of a pregnant female means a loss to the stock of one adult and 

 one potential calf. This cannot justly be regarded as the killing of two whales, for if that 

 were so we could equally regard the killing of a resting female as the loss of two (or more) 

 whales on the ground that it would normally become pregnant next year (and on 

 subsequent occasions). A distinction must therefore be recognized between actual and 

 potential whales. This does not mean, however, that the killing of an immature whale is 

 no more damaging than the killing of, say, a mature resting whale, for it must be 

 supposed that in natural conditions there is a limit to the possible number of calves any 

 female can have. When an immature whale is killed all these potential calves are lost, 

 whereas when an adult female is killed the chances are that she has already reared a 

 certain number of her possible calves, and there are so many fewer to come, according 

 to her age. To be added to this is the far better yield from an adult, so that from both 

 points of view the killing of immature whales is undesirable. It is noteworthy also that 

 a better yield of oil is to be expected from pregnant than from lactating females. 



Thus in general it is better to kill Fin rather than Blue or Humpback whales ; males 

 rather than females ; large and old whales rather than small and young or immature 

 whales; resting rather than pregnant females; and pregnant rather than lactating 

 females. 



WHALING IN DIFFERENT REGIONS 



It has been shown (p. 236) that the different whaling grounds of the southern hemi- 

 sphere fall naturally into certain major groups according to their geographical positions 

 and the species of whales taken. In the southern summer we have the whaling on the 

 Antarctic pelagic grounds and at South Georgia, and the practically insignificant former 

 industries of the Falkland Islands and Kerguelen Island. In the winter when the whales 

 have migrated to the north we have the subtropical stations (principally Natal and Cape 

 Province) and the tropical centres such as off the Congo and Western Australia. Details 

 of the species of whales taken at the various whaling centres are given in Table 10 

 (p. 234). Certain differences between the Antarctic summer whaling and the winter 

 whaling in warmer waters may be seen at a glance from this table and were referred to 

 on p. 236. The tropical stations (Congo, Brazil, Angola, East Africa, West Australia, and 

 Madagascar) take hardly anything but Humpbacks (except at Angola) ; the subtropical 

 stations (Walvis Bay, Natal, Cape Province and Chile) take Blue, Fin, Humpback, Sei 

 and Sperm whales in various proportions ; the Antarctic industry depends mainly on 

 Blue and Fin whales, sometimes also taking substantial numbers of Humpbacks. In 



