THE MIGRATION OF BIRDS 263 
safely assert that the journey is undertaken principally for 
the purpose of nesting. Everybody is familiar with the way 
hens and turkeys like to “ steal their nest,’ — that is, to go 
some distance from their accustomed haunts and make their 
nest in a secret place. The long journey to the North is sup- 
posed to be due to the same instinct. Moreover, here is where 
these birds were reared and where the older ones have already 
raised families in former years. This, no doubt, they regard 
as home, and the South merely as a place to spend the winter. 
So when the breeding season approaches they come home. 
Return to Same Region. — Though a bird does not generally 
return to its former nest another year, it does come to approxi- 
mately the same region where it was reared. But the changes 
incident to the settlement of the country also bring about a 
change in the bird life, and so the range of a bird may be grad- 
ually changed or extended. In such cases the route it travels 
remains the same that was followed originally. Thus, the 
Bobolink of Dakota comes from Brazil by way of Cuba and 
Florida. The ancient Bobolink of our eastern states traveled 
by that route, the knowledge of that route has been taught 
to each succeeding generation, and all American Bobolinks 
still go and come by it, although they have gradually extended 
their territory westward to Montana. 
