CHAPTER XI 



WINTER FEEDING 



It is an established fact that the main factors 

 in bird migration are weather and food. Tem- 

 perature is of surprisingly small account in its 

 effect on birds. This is shown by the example of 

 almost Arctic birds thriving in captivity under 

 the same climatic conditions as those whose 

 habitat is some portion of the equatorial zone, in 

 which the temperature never varies more than ten 

 degrees thruout the year. Undeniably, during 

 terrific storms, in which the birds become soaked 

 and then the water freezes, many hundreds of 

 birds die in a day or night; but as a rule these 

 conditions are rare and it is not from them that 

 birds flee to southern lands. 



The most potent factor is food, whether it be 

 with the Flycatchers, the insects which have 

 disappeared for the winter ; with the Osprey, the 

 fish; or in the case of the Finches, the lack of 

 seeds. To cite instances which prove the truth 

 of the theory is as useless as it would be facile. 



Seeing thus how large a part the food supply 

 plays in the lives of birds, we can realize how 

 greatly we may aid the birds by remedying the 

 scarcity which drives them hundreds of miles 

 away. When supplying food in winter consider 

 54 



