526 EXTINCT AND VANISHING MAMMALS 



fewer Humpbacks were taken. Nevertheless the taking of the 

 larger species coincided with a definite decrease in the numbers 

 of Humpbacks available . . . The whalers state that the 

 decrease in its numbers is due to its being frightened away from 

 its former haunts, but there seems to be no valid reason why 

 this species should be more easily frightened than any other, 

 unless it is very attached to certain definite lines of migration. 

 There appears to be some evidence in support of this possi- 

 bility . . . The decrease in numbers, however, is prob- 

 ably due partly to excessive slaughter, because the Humpbacks 

 have never returned in their former huge numbers to South 

 Georgia. Their capture is now prohibited there, except under 

 special license, given only when other species are very scarce" 

 (Matthews, 1937, p. 82). At first, from 1908 onward, hump- 

 backs were taken in very large numbers at the South African 

 whaling stations as at Durban, but the more recent figures 

 (Matthews, 1937) show a decline from the 1924 peak of nearly 

 200 to less than 100 in 1927. During the same years the catch 

 of blue and finback whales was maintained at between 500 

 and 600 annually. 



In the waters of Western Australia a similar phenomenon 

 was observed. In 1913 a total of 654 was taken; in the next 

 year, 1,900; in 1915, less than 900; and in 1916, less than 200. 

 The whales taken were evidently "on their way to and from 

 their breeding grounds a little to the north" so that as a result 

 of the inroads on their numbers, the pursuit was abandoned as 

 less profitable than other trades. It was renewed, however, in 

 1925, when of some 670 whales taken the greater part were 

 humpbacks. 



Matthews (1937) concludes that "the reason for the great 

 decrease in numbers of Humpback whales, off the South 

 African coast at any rate, is not far to seek . . . Most of 

 the catch at the South African whaling stations consists of 

 immature whales, and in addition . . . whaling in these 

 localities is conducted during the breeding migration, so that 

 it is small wonder that a species so harassed is becoming 

 scarcer. In southern seas the catch consists predominantly 

 of mature animals on their feeding migration, and the decrease 

 in numbers there is probably due not only to excessive slaughter 

 on the southern grounds but also to the killing of large numbers 

 of breeding and pregnant whales in temperate and tropical 

 latitudes." 



