2 14 Wild Life in a Southern County 



most two, seasons only ; for it is noticeable that when 

 rooks build at a distance from the centre of population 

 they are some time before they finally decide on a site, 

 abandoning one place after another. But the nests form- 

 ing the principal streets are piled up to a considerable 

 height — fresh twigs being added every year — and are also 

 thick and bulky. The weight of the whole must be a 

 heavy burden to the trees. 



Much skill is shown in the selection of the branches 

 upon which the foundations are laid. In the first place, 

 the branch must fork sufficiently to hold the bottom twigs 

 firmly and to give some side-support. Then it must be a 

 branch more or less vertical, or it would swing with the 

 wind too much up and down as well as to and fro. Thirdly, 

 there should be a clear or nearly clear space above the nest 

 to give easy access, and to afford room for it to increase 

 in size annually. For this reason, perhaps, nests are 

 generally placed near the top or outer sides of the tree, 

 where the boughs are smaller, and every upward extension 

 reaches a clearer place. Fourthly, the bough ought not 

 to be too stiff and firm ; it should yield a little, and sway 

 easily, though only in a small degree, to the breeze. If 

 too stiff, in strong gales the nest runs the risk of being 

 blown clean out of the tree. Fifthly, no other branch 

 must rub against the one bearing the principal weight of 

 the nest, for that would loosen the twigs in time, and 

 dislocate the entire structure. Finally, rooks like an 

 adjacent bough on which the bird not actually engaged 

 in incubation can perch and ' caw ' to his mate, and 

 which is also useful to alight on when bringing food for 

 the young. 



It may be that the difficulty of finding trees which, 

 afford all these necessary conditions is one reason whyi 



