Robbers of the Air 



woe betide that poor mother bird's treasures. In the 

 spring of 1920 I watched a carrion crow hunting a 

 rough, bent-clad pasture on a Westmorland fellside. It 

 flushed a rather exposed , grouse from her nest, but 

 catching sight of me not more than a gunshot away, 

 instead of alighting sheered off and disappeared in a 

 thickly wooded ghyll half a mile away. Although 

 baulked for the moment this sable marauder had 

 evidently made careful mental notes of its find, for the 

 eggs afterwards disappeared at the rate of one per day. 



A strange thing I have noticed over and over again 

 about both this bird and the great black-backed gull is 

 that if the field naturalist should find and examine the 

 nest of a bird of any other species in a neighbourhood 

 where either of these egg thieves is common that nest is 

 almost certain to be robbed. In the case of the gull it 

 is perhaps nothing very wonderful, because several in- 

 dividuals are generally hovering high overhead keenly 

 watching and noting proceedings. The crow, however, 

 does not, as a rule, avail itself of such an advantage, 

 and in all probability has its curiosity aroused by dis- 

 turbed grass or foliage, and conducts a remunerative 

 investigation. 



The hoody, or grey crow, is as intrepid an egg stealer 

 as its better-known relative just treated, and is equally 

 cunning. I have known a pair of birds of this species 

 utterly despise poisoned fowls' eggs cleverly disposed for 

 their temptation, and instead wage deadly warfare upon 

 well-grown chickens in a neighbouring farmyard. 



Our very familiar friend the rook will sometimes 



49 



