234 WARFARE BETWEEN DIFFERENT SPECIES 



the other. Yet a Whinchat, when it has 

 estabhshed itself, is most pugnacious ; it not 

 only attacks every bird of a similar size that 

 approaches its position, but its behaviour under 

 such circumstances bears the impress of unusual 

 determination ; and if we were to take a male 

 and place it in the position of the Stonechat, we 

 should find that its nature would change, that 

 the presence of the Stonechat would evoke a 

 hostile response, and, conversely, that the 

 instinct of the Stonechat would not be suscep- 

 tible to stimulation. Hence it is clear that the 

 nature of a bird when on migration is not quite 

 the same as it is when its destination is reached ; 

 that the positions occupied from time to time 

 during the journey carry no meaning, or, rather, 

 are not brought into relation with its life in 

 quite the same way as is the position which it 

 finally occupies ; and further, it is clear that the 

 interest it displays in other species undergoes a 

 somewhat remarkable transformation when at 

 length its destination is reached. 



This altered nature of the migrant is a fact 

 of some importance in relation to our present 

 subject, but it does not stand alone — the same 

 characteristic is observable in other phases of 

 bird life. Some of the residents, the Buntings 

 and the Finches for example, occupy their 

 breeding ground very early in the year, and it 

 often happens that the situations which they 

 select are not capable of supplying them with 

 food so early in the season, though at a later 

 date food will be there in abundance ; so that 



