CHAPTER II 



THE VERNAL MIGRATION 



With Observations on the Scope and Causes 

 of Migration 



Among the earlier signs of returning - spring is the com- 

 mencement of migration : a phenomenon so complex and 

 yet so interesting that I propose making a few remarks on 

 its scope and on the causes which produce it, even at the 

 risk of alarming some readers who may perhaps think 

 my book a mere maze of technicalities. 



This great bi-annual bird-movement commences as 

 early as February, but the initial stages of the vernal 

 immigration to the moorlands are all but imperceptible. 

 During the cold and wintry months of February and 

 March, very large numbers of birds, many from distant 

 lands, keep quietly arriving day by day, and distribute 

 themselves over the moors. In the aggregate their 

 numbers are immense ; but, when distributed over so 

 wide an area, their advent is inconspicuous, and may 

 easily be overlooked, especially as on first arrival the 

 new-comers are shy, since they have not then thrown off 

 their wild character, or assumed the careless disposition 

 of spring. Moreover, these new-comers are not new 

 species suddenly appearing. They are, in most cases, 

 merely reinforcing others of their own kind which have 



