NATURAL HISTORY OF SOUTH AFRICA 



The Harrier Hawk. 



(Genus — Polyboroides. ) 



Diet. — Rats, mice, lizards, snakes, frogs, young grass birds, 

 and insects. 



The Vulture. 



(Genera — Gyps., Pseudogyps^ Lophogyps^ Neophron^ and 

 Necrosyrtes.) 



Diet. — The vultures of the above genera all feed on carrion. 

 The well-known kolbe's vulture or witte aasvogel attacks and 

 devours helpless ewes when lambing if carrion is scarce. The 

 black vulture or zwarte aasvogel has also been observed doing 

 likewise. For this reason farmers have poisoned vultures in 

 great numbers. It must be borne in mind, however, that the 

 cattle disease known as lamziekte is largely due to cattle chewing 

 the bones of animals which have died and rotted on the veld. 

 Vultures, by picking the bones clean and freeing them of decayed 

 flesh, may be very helpful in controlling this dreaded disease. 



The Osprey. 



[Pandion halicetus.) 



Diet. — The osprey frequents the mouths of tidal rivers and 

 shallow lagoons along the coast, and feeds almost exclusively on 

 fish. 



The Secretary Bird. 



{Serpentarius secretarius.) 



Diet. — This handsome and unique bird seeks its prey out 

 on the open veld and treeless hillsides. It walks great distances, 

 and seldom flies unless alarmed. Its diet is very varied, and 

 consists of nearly all the species of small creatures which live 

 on the ground. It preys largely on rats, mice, small tortoises, 

 insects, snakes, and the eggs and young of ground birds ; hares 

 also add to its dietary. The secretary bird is of considerable 



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