8o Northern Observations of Inland Birds 



He, however, was not profiting by his industry, for 

 another jackdaw, an idler, was watching him closely. 

 Ever}^ time he flew away this second individual darted 

 into the cranny he had just left, appeared a second later 

 with something in his beak, and promptly disappeared 

 into another cranny several yards away, there to remain 

 hidden till his industrious neighbour was again out of 

 sight. E\-idently the rightful owner had his suspicions 

 that things were not quite as they should be, for as time 

 passed he became more and more ruffled and agitated 

 when he reappeared from his den, having observ'ed that 

 his store was not growing ! 



For many years my grandfather did even.'thing reason- 

 ably possible to establish a rooker}^ in the elm grove of 

 his grounds — even to the length of hiring sharp-witted 

 crooks, who boasted the possession of secret knowledge 

 whereby rook colonies could be established. The placing 

 of one or two old nests in the trees, and the suspension 

 of rook shooting in surrounding rookeries, are the only 

 measures of which I know likely to produce results. 



Rooks, however, cannot be induced to nest in trees 

 which are old and beginning to rot. They evidently 

 know that such trees are unsafe, and will forsake a tree 

 in which they have nested for years as it begins to show^ 

 signs of decay. It is very probable that the rooks are 

 guided as follows. The branches in which they nest 

 must be supple and yield to the wind, otherwise there 

 is a great danger of the branches snapping oflF in a hea\^ 

 storm, or of the nest being torn out from its rigid settings. 

 As a tree becomes old its branches grow stiff, especially 

 the topmost branches w-hich the rooks favour, owing to 

 the flow of sap becoming more and more restricted by 

 the dying of the trunk. 



Of late years rooks have become very destructive to 

 the nests of game birds, which is regrettable, as it has 



