FEEDING 



257 



of whale intestines and also whale faeces have a characteristic brick-red 

 colour. Whalers are not very keen on this colour as it darkens the oil, even 

 though it does not affect its quality. However, since oil is generally judged 

 by its colovu-, the crew of factory ships always see that all intestinal matter 

 is scrubbed off the decks so as not to pollute the boilers. 



Euphausia superba, the Antarctic krill, takes two years to reach full 

 maturity after it is hatched out. The stomachs of whales therefore contain 

 krill of different sizes and ages, one-year-old krill being from i^-if inches 

 long and two-year-old krill from 2-2^ inches. Whalers, who were formerly 

 misled into believing that because of these differences in size Antarctic 

 krill consisted of two distinct species, called the smaller 'Blue Whale 

 krill' and the larger 'Fin Whale krill', since Blue Whales were thought to 

 feed mainly on the former, and Fin Whales on the latter. Closer investiga- 

 tions have, however, shown that they were wrong and that both 'species' 

 can be found in either whale. Particularly in the Antarctic, there is so 

 much krill that even the greediest whales need never go short. From 

 Mackintoshs's summary of the investigations of the Discovery Committee 

 (1942), it appeared, for instance, that about 75 per cent of captured Blue 

 Whales, 55 per cent of captured Fin Whales, and more than 90 per cent 

 of captured Humpback Whales had their stomachs filled to capacity. 

 In the tropics and sub-tropics, where food is scarce in the areas of the 

 principal land stations, the stomachs of whales are, however, generally 

 quite empty, a subject to which we shall return in a later chapter. 



Meanwhile, a word or two about the point raised by animal lovers to 

 the effect that the lives of whales might be spared and the whole procedure 



Figure ijj. Unicellular plants and 

 animals found in the stomachs of 

 krill. They are predominantly dia- 

 toms of which the majority belong 

 to the species Fragilariopsis 

 antarctica {double arrow). The 

 single arrow points to Cocconeis 

 ceticola which is often found on 

 the skin of whales {Barkley, 1946.) 



