NATURAL HISTORY OF SOUTH AFRICA 



special duties to perform in war. So it is with the 

 various regiments (species) of birds in their endless 

 war on the insect army. During the time of the 

 year when their services are in special request, birds 

 are most active in their war of extermination of the 

 insect hosts. Yet we stupidly admire the feathers of 

 wild birds in ladies' hats, and encourage our boys to 

 collect birds' eggs. A farmer, whose son or Kafir 

 employee robs a nest of its contents or kills a pair of 

 breeding birds, leaves unslain at least 20,000 insect 

 pests which rapidly mature on his succulent crops. 

 Half of these are females. In a few days after their 

 emergence from the chrysalis each of these deposits 

 from 500 to 10,000 eggs on his crops, pasturage, and 

 trees. The eggs hatch in a few hours or days, and a 

 host of caterpillars emerge to begin feeding voraciously. 

 Thus within a period of two months the destruction 

 of a single pair of breeding birds, their eggs, or young, 

 results in an active ravening army of more than a million 

 caterpillars or other forms of insect larvae. Verily, 

 I say, we have eyes, but we see not ; ears, but we hear 

 not ; brains, but we reason not. The house fly, the 

 blood-sucking fly, and the mosquito sow disease and 

 death broadcast amongst us and our stock animals, 

 yet we persecute the birds which destroy these flies. 

 The wagtail, the fly-catcher, the swallow, swift, and 

 martin devour flies and mosquitoes wholesale ; we 

 calmly stand by while our boys and the coloured 

 children destroy these eminently useful birds' nests or 

 rob them of their contents. 



Reckoning the time it takes for a bird to digest 

 194 



