WHY BIRDS TRAVEL 



fruit, but eggs, and the eggs when incubated give 

 birth to birds. So we see that in reality birds, 

 as well as trees, bloom ; that both have their regu- 

 lar season of blooming and of reproduction, and 

 this season is generally in the spring when in- 

 creasing warmth sets the sap flowing. 



It is true that the Pelicans of Pelican Island 

 begin to nest when the weather is becoming 

 colder instead of warmer. Why they should do 

 so no one knows. On the west coast of Florida 

 the same kind of Pelicans do not nest until April. 

 This is doubtless the proper nesting time, but for 

 some as yet unknown reason the birds of eastern 

 Florida have chosen a time of their own. 



The important fact here is that they all go at 

 the same time and for the same purpose. In 

 everything, therefore, but length, their journey 

 to Pelican Island is as much a migration as is 

 that of a bird which flies from the tropics to the 

 Arctic regions. Both go each year at a certain 

 season; both go to nest; both are prompted to 

 start by the awakening of the nesting instinct 

 with its desire to go to a proper place in which 

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