FLOCKS OF BIRDS 31 



tion, with birds perhaps less widely known as with 

 those universally recognised such, for instance, as 

 shrikes. The winter when the cry was raised that 

 there were no birds, that the blackbirds and thrushes 

 had left the lawns and must be dead, and how wicked 

 it would be to take a nest next year, I had not the 

 least difficulty in finding plenty of them. 



They had simply gone to the water meadows, the 

 brooks, and moist places generally. Every locality 

 where running water kept the ground moist and per- 

 mitted of movement among the creeping things which 

 form these birds' food, was naturally resorted to. 

 Thrushes and blackbirds, although they do not pack 

 that is, regularly fly in flocks undoubtedly migrate 

 when pressed by weather. 



They are well known to arrive on the east coast 

 from Norway in numbers as the cold increases. I see 

 no reason why we may not suppose that in very severe 

 and continued frost the thrushes and blackbirds round 

 London fly westwards towards the milder side of the 

 island. It seems to me that when, some years since, 

 I used to stroll round the water meadows in a western 

 county for snipes in frosty weather, the hedges were 

 full of thrushes and blackbirds quite full of them. 



Now, though there were thrushes and blackbirds 

 about the brooks by London last winter, there were 

 few in the hedges generally. Had they, then, flown 

 westwards ? It is my belief that they had. They 

 had left the hard-bound ground about London for 

 the softer and moister lands farther west. They had 

 crossed the rain-line. When frost prevents access to 

 food in the east, thrushes and blackbirds move west- 

 wards, just as the fieldfares and redwings do. 



That the fieldfares and redwings do so I can say with 



