CHAPTER XXXIV 



Local migration Pairing of birds for life Courtship, and the cause of song 

 Plumage Stonechats Lichens as food Seasonal moults in Chats 

 Welsh names. 



So comparatively few birds spend the winter round 

 Llanuwchllyn that it is a very favourable station for 

 observing movements of local migration. Indeed, the fact 

 that it lies outside any of the regular routes taken by merely 

 passing species lends additional interest to the noting of 

 the arrival and departure of those that come to breed. 

 Whether some of these may have wintered in places not 

 very remote, matters not ; here they are as much mere 

 sojourners, with a single purpose, as if they had come from 

 the centre of Africa. Some of them may never have left 

 the British Islands ; though from the fact that they often 

 arrive in considerable bands, the sexes often separately, I 

 should be inclined to suspect that the majority of them had 

 travelled further, and had not dawdled much by the way. 

 In so restricted an area, scant alike in cover and in resident 

 birds, anyone moving about a good deal, and having an eye 

 for such things, can hardly fail to notice some of the little 

 flocks probably within a few hours of their arrival in the 

 valley. In some species, as the Pipits, it is not possible 

 to distinguish between the sexes ; but in others, like the 

 Chats, the males are easily recognised, and are generally 

 seen to arrive by themselves, and to precede their partners 

 by a few days, or may be even weeks. This is very 

 interesting, not only as showing a similar sequence to that 

 usually observed upon the east coast, and as indicating that 

 there has been no tarrying en route, but also because it raises 

 the question of whether the sexes winter together, and 

 whether pairing for life can be the rule amongst such birds. 



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