396 WHALES 



therefore encouraging to note that at recent expert meetings, the criticism 

 of, inter alia, the Dutch team, has led to new research being initiated. 



All final decisions must, of course, be based primarily on the Inter- 

 national Whaling Statistics which, since 1930, have published detailed 

 information on all whales caught in the Antarctic. A single glance at 

 Fig. 2 1 7 shows that the seasons have become steadily shorter ever since 

 1932, and particularly since the Second World War. While 16,000 

 B.W.U. were caught annually by fifteen expeditions in 121 days immedi- 

 ately after the war, the quota of 15,000 units was caught in only fifty-eight 

 days during 1955-6, which was, however, an exceptionally short season. 

 (Since then the season has been extended to seventy days, as it was in 

 the preceding year. In 1959-60 the season was very long and the catch 

 figures were bad.) This short duration of the season might lead one to 

 suspect that the whale population had strongly increased, particularly 

 when we consider that, although the number of permitted B.W.U. fell 

 by 1,000, the actual number of captured Baleen Whales has increased 

 by 4,250 since 1946-7. (This is due to the fact that Fin Whales account for 

 an increasing proportion of the catch, and that, in the definition of the 

 B.W.U., two Fin Whales are equivalent to one Blue Whale.) 



However, our suspicions are not necessarily correct, since whaling 

 techniques, too, have changed radically over the past decade. Factory 

 ships, whose average tonnage in 1946 w-as 13,212, had an average capacity 

 of 16,093 tons in 1955, and thus a far greater potential output. Moreover, 

 we can see at a glance from Fig. 218 that the number of catchers per 

 factory ship increased from 9 to 15 and their average horse-power from 

 1,302 to 1,945. (The slight drop during 1953-5 ^^^ ^^^ ^^ ^^^^ agreed 

 limitation of the number of catchers per factory ship, since then repealed, 

 and again introduced in 1957-8.) Nor can we go very much by the average 

 number of whales caught per catcher per day, since the number of B.W.U. 

 per Catcher's Day's Work (C.D.W.) tends to increase with the increasing 

 capacity of the catcher, and to decrease with the increasing number of 

 catchers per factory ship, as the number of carcasses a given factory ship 

 can process is, of course, limited. Needless to say, the statistics do not tell 

 us how many hours a given catcher is kept idle because the mother ship 

 has its hands full (all carcasses must be processed within thirty-three 

 hours, and stores cannot be accumulated) nor how many catchers are used 

 as buoy-boats for towing dead whales to the factory ships. Moreover, 

 it will generally take longer to capture two Fin Whales than to capture 

 one Blue Whale, and so a comparison of annual catch results does not lead 

 to reliable conclusions about whale populations. 



While, therefore, the increase in B.W.U. per C.D.W. shown by the 

 graph of Fig. 219 cannot be interpreted as meaning that the number of 



