NATURAL HISTORY OF SOUTH AFRICA 



food supply in any given area. It is a matter of the 

 survival of the fittest. The size of the territory is in 

 relation to the quantity of food required for the 

 sustenance of a pair of birds and their young. A 

 pair of fiskal shrikes will often be content to own 

 one small garden plot, finding in it ample insect life 

 for their needs. 



Out in the arid veld in drought-stricken districts 

 there is often only one pair of birds inhabiting a 

 comparatively large territory. In a certain dry district 

 I noticed there was one pair of fiskal shrikes to about 

 ten morgen of land. 



Often, owing to a scarcity of nesting sites, birds 

 are forced to congregate in numbers in small areas. 

 In these instances long journeys for food are often 

 necessary. Others are naturally sociable in their 

 habits, and build their nests in proximity to one 

 another for preference. 



It has been asserted that the brilliant plumage of 

 many male birds of territorial habits, such, for instance, 

 as the sun birds, are warning colours, viz., so that, 

 perched on a bush, the owner of the territory will be 

 conspicuous to all and sundry who may have any 

 inclination to intrude. The weakness of this theory, 

 however, is that there are as many species of birds of 

 beautiful plumage which are not territorial as there are 

 of those which have this habit. Birds, the males of 

 which take on beautiful plumage only on the approach 

 of the nesting season, will be found to be the species 

 which are polygamous, or which have a different mate 

 each season. There is, consequently, a definite object 



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