Nests in Trees 



should be so partial to thorns for the construction of its 

 nest is hard to say. Perhaps they are placed there to 

 chastise likely egg-stealers, including schoolboys. 



A nest which deserves a place in any discussion of bird 

 architecture is that of the social weaver-birds or gros- 

 beaks. As their name indicates, these birds live to- 

 gether in flocks and have developed the social habit to 

 a degree that is rare among birds, to such a point, in fact, 

 that many individuals construct a common nest, or, to 

 be more exact, they live in separate compartments under 

 one roof. The entire edifice resembles nothing so much 

 as an enormous umbrella. Sometimes it contains more 

 than a cartload of grass, and over three hundred and 

 twenty nests have been counted under a single shelter, 

 each one containing a pair of birds bringing up four or 

 five youngsters. The nests are built of a plant known as 

 bushman grass, and they are always constructed in the 

 branches of the camel-thorn acacia. 



In the beginning, a single pair of birds build their nest, 

 by hanging the leaves of the bushman grass on a suitable 

 branch, and weaving and plaiting it till it forms a roof. 

 Beneath this roof the actual nest is built. Other sociable 

 weaver-birds join in the enterprise, and the edifice grows 

 by degrees till it looks like " a mass of grass pierced by 

 numerous holes," each hole being the entrance to a nest. 

 At the end of the season, of course, the old nests are 

 abandoned. When Nature again calls the birds to the 

 duties of nest-building, they do not seek another site, but 

 enlarge the last year's roof and build another layer or 

 layers of nests round the old ones, after the manner of 

 the new cells in a wasp's nest. Year by year the same 

 edifice is used. Small wonder, then, that these nests fre- 

 quently attain enormous proportions. 



The weaver-birds and hang-nests are the eccentrics of 

 the bird world, so far as their nests are concerned. Using 

 wiry grasses and fibres, for the most part, they weave 

 them so skilfully that they appear to be the result of the 



127 



