NATURAL HISTORY OF SOUTH AFRICA 



BIRDS AND INSECTS 



The well-known wire-worm and cockchafer grubs 

 are the larvae of beetles. They live chiefly in culti- 

 vated soil for three to five years before changing 

 into beetles. Meanwhile they are busy all the time 

 devouring the roots of crops and useful pasturage 

 plants. They attack all crops with the exception of 

 mustard; and in South Africa they feed all the year 

 round. We have no chemical or other agent by which 

 we can kill these grubs. A host of species of birds 

 feed on wire-worms, cut-worms, and cockchafer grubs. 

 Amongst others they are eagerly sought after by 

 rooks, hoopoes, starlings, thrushes, larks, plovers, 

 partridges, pheasants, quails, and guinea-fowls. When 

 the grubs are turned up by the harrow, plough, or 

 spade, a host of other species of birds pounce upon 

 and devour them. 



It has to be remembered in cases of stomach examina- 

 tion that soft animal food is digested with great rapidity 

 and leaves few traces, whereas grain and seed remain in 

 evidence a much longer time. 



The army moth is another dreaded South African 

 scourge. A vast army of moths settle by night upon 

 the succulent pasturage and lay their eggs. Presently 

 an uncountable host of caterpillars emerge from the 

 eggs and eat off the grass and crops as effectually as if 

 they had been burned by fire. They travel in a vast 

 army, eating every green blade and leaf before them. 



The night jar and insectivorous bats prey upon 

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