FEAR IN BIRDS 195 



remaining a minute or two in hiding, they recover 

 courage enough to set out again to continue their 

 eccentric progress. 



We see, then, from all this, that what I have 

 called the " Passion of Migration " is an emotion which 

 accompanies the instinct, the act; that it is fear, 

 and is not the cause but an effect (an incidental 

 effect, one may say) of the impulse impelling birds 

 to migrate. 



Fear in birds is caused by something seen or 

 heard: scent does not come in here, as it does in 

 the case of mammals. Something inimical in the 

 bird's life, which he recognises as a danger, in some 

 instances by experience, but as a rule by tradition 

 handed down from generation to generation. Thus, 

 a bird in England flies from a man, not because he 

 has been hurt by a man (although this does some 

 times happen), but because his parents and other 

 adults he consorts with after leaving the nest, have 

 invariably uttered a warning note on his approach. 

 This has infected him, and for the rest of his life man 

 is viewed as a dangerous being, and the lesson is 

 handed on to his offspring. The effects of this lesson, 

 we know, may be overcome, and some of us have 

 stroked eiderdown ducks and thrushes and black- 

 birds sitting on their eggs without frightening them, 

 and I have also been accustomed to have wood- 

 pigeons in the London parks fly on to my hand to 

 be fed. But in a vast majority of wild birds it is 

 practically an ineradicable habit, although, as we 

 see, not instinctive nor yet an inherited habit. 



