NATURAL ENEMIES OF BIRDS 



the nests of birds which build in the neighbourhood 

 of its watery haunts. This lizard is able to climb 

 trees with ease, and the destruction it causes in the 

 ranks of useful birds is not balanced by the harmful 

 insects it disposes of. In fact this monitor lizard 

 may be safely regarded as a reptile of little economic 

 value in South Africa. In Central Africa it performs 

 a useful service in reducing the crocodiles by feeding 

 on their eggs and young. It feeds largely on fresh- 

 water crabs, which are useful scavengers ; and also 

 on frogs (Rand) and toads (Bufo). Frogs and toads 

 are insect feeders, and therefore of considerable 

 economic value. 



The various wild cats, genets, and muishonds prey 

 on birds to a more or less considerable extent, but 

 their depredations are mostly confined to ground 

 birds. As an offset against the harm they do to 

 bird life, they prey largely on rats and mice. The 

 mungoose and muishond render the highest services 

 to man in this way. I have ascertained, after many 

 years of close observation, that the chief diet of these 

 little carnivorous animals consists of rats and mice. 



Squirrels destroy the eggs and young of birds to a 

 considerable extent in localities where these animals 

 are numerous. The Carolina squirrel {Sciurus caro- 

 linensis) was introduced into Cape Town many years 

 ago, and has multiplied so alarmingly that it is now a 

 serious menace to the fruit grower and to our native 

 birds. 



The vervet monkeys, which dwell in the wooded 

 districts of South Africa, are unqualified enemies of 



vol. i. ' 241 16 



