FIELD AND STUDY 



keeps him in check. The defenseless rabbit, upon 

 which so many creatures prey, easily holds its own 

 because it is so very prolific. It also has another 

 advantage; it can and does sleep with its eyes open. 

 The flying squirrel would seem to have a great 

 advantage over the chipmunk, yet it is far less 

 numerous in our woods; it pays for its wings in some 

 way; it is probably less handy and resourceful. 

 Few animals will molest the skunk, yet the world 

 is not filled with skunks; where they are found side 

 by side, the woodchuck, which has many more nat- 

 ural enemies, is far more abundant, not because it 

 is more prolific, which does not seem to be the case, 

 but because, among other things, its food-supply is 

 simpler and more universal. The limitation of the 

 natural food-supply is, of course, the great factor 

 in the limitation of animal life everywhere. If our 

 spring is late and cold, the robins nest later, and 

 have smaller broods than during a warm, early 

 spring. 



The gray squirrel is far less numerous in my 

 locality than the red because, in my opinion, he is 

 far less resourceful; he is not the same miscella- 

 neous feeder, and hence is much more restricted 

 in his range. The red squirrel, when hard put to it, 

 will come to your very door and chip up green ap- 

 ples and pears for the meagre supply of seed in 

 them. In May and June, when other supplies fail, 

 he helps himself out with birds' eggs and with young 

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