Birds by Land and Sea 



upon the limited arithmetic of the Australian aborigine 

 " One, two, three, and a great many ! " 



It is not long since men used to wonder if birds 

 migrated : shall we ever know enough to cease to 

 wonder that they migrate ? For, if it be held that 

 birds change their ground because of climatic changes, 

 surely the birds that quit the north to winter with 

 us when food is scarce, should not leave us with the 

 advent of spring and a sufficiency of food. But if it 

 be argued that failure of a supply of food of the right 

 kind impels our summer visitors to migrate in the 

 autumn, how should they know that after a long and 

 sudden passage to the south they would find at the 

 end of their journey what was lacking here ? For 

 birds, when they migrate, are not urged forward by 

 a famine line, so to say, forcing them farther and 

 farther south as the northern winter closes down 

 behind them ; but, as if by a common inspiration, 

 enter at once upon a long and arduous voyage, during 

 which thousands of them perish, and such as arrive 

 at the distant goal do so exhausted and emaciated by 

 the violent effort. Climate and food undoubtedly 

 influence migration, but, as is often the case in 

 reasoning about birds, there is still an unexplained 

 remainder ; for, as Warde Fowler truly says in his 

 delightful book, "A Year with the Birds," "Birds 

 have ways, and reasons for them, which man is very 

 unlikely ever to be able to understand." 



This year the migrants put in an appearance very 

 early in the south of England. The wheatear was 



