NATURAL HISTORY OF SOUTH AFRICA 



For instance, the little locust bird or kliene 

 sprinkhaanvogel (Glareola melanopterd) was to be 

 found in large flocks every summer season in the 

 neighbourhood of Pietermaritzburg. The youths of 

 the city, finding the bodies of these faithful allies were 

 good for making pies, began a campaign of extermina- 

 tion. Within five years not a single bird of this 

 species was to be seen, not because they had all been 

 killed, but, finding themselves so inhospitably received, 

 they no longer visited their old hunting grounds. 

 The result was a plague of grasshoppers, which for 

 many years devastated the pasture lands and made 

 gardening almost an impossibility. 



The extermination or driving away of a single 

 species of bird may, and often does, result in a 

 plague of some sort. 



For instance, in Australia, grasshoppers every 

 summer season are a menace to the farmer. Should 

 their natural enemies, the birds, be reduced in numbers 

 for any reason, the grasshoppers rapidly multiply and 

 lay waste the crops and pasturage. 



The straw-necked ibis (Carphibis spinicollis) is the 

 bird which is mainly responsible for holding these 

 pests in check. A rookery of these ibises was visited, 

 and it was estimated 200,000 birds were breeding 

 there. Some specimens were procured, and it was 

 ascertained by actual counting that the average contents 

 of the crop of a single bird totalled 2,400 young grass- 

 hoppers and some snails and caterpillars : 200,000 

 birds would therefore dispose of about 480,000,000 

 grasshoppers per day. This vast number would 



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