List of Birds Examined. 55 



ROOK. 



Corvut frugilegusy Linn. 



Few birds are better known than the rook, partly owing to the 

 fact of its living in flocks, and also that it usually selects for its 

 breeding places a situation close to human habitation. 



In some localities it has undoubtedly rapidly increased during 

 the last ten years ; this is particularly so in Scotland, where it is 

 said to destroy eggs on a large scale. 



During the autumn months there is a large migration from the 

 Continent on our east coast, and a return migration has been noted 

 in the early spring. 



The nest is usually built about the middle of March, but in 

 some localities the birds have been observed building both earlier 

 and later. Tall trees are usually selected, but sometimes firs, 

 pollard-willows and even bushes have been chosen, and occasionally 

 chimney-tops and church spires. 



The nest consists of twigs and turf, lined with roots and straw. 

 Here the three to five bluish-green eggs, blotched and streaked 

 with olive-brown, are laid. 



Breeding commences when the birds are nearly two years old. 



Excepting the house-sparrow, no other wild bird has had so 

 much attention devoted to its economic status as has the rook. 



Gilmour's (54) well-known investigation, in which he made 

 post-mortems of three hundred and fifty-five birds, showed that : 



Cereal grain and husk occurred 290 times or 58 per cent. 



Insects, grubs, etc. ,, 116 ,, 23 ,, 



Miscellaneous ,, 60 ,, 12 ,, 



Roots 36 7 



Leaves ,, 



Flowers ,, ,, ,, 

 Fruits and seeds, not 



cereals 



"These figures show that at least three-fourths of rook-food 

 (81 per cent.) is cereal grain and husk, with insect and grub ; ialso 

 that grain and husk are at least twice as frequently met with as 

 insects and grubs." 



"Taken altogether," he concludes, "the rook has almost no 

 claim to agricultural regard." 



