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OUR WINTER BIRDS 



try in which they have settled, if they are to advance 

 the boundaries of their range. This fact places a 

 trying test on their vitality and endurance, and only 

 too often they are called upon to pay the penalty 

 which falls to the lot of the leader. 



During a succession of favorable years they thrive 



Carolina Wren 



and multiply and one hears of them from places at 

 which they had not been previously seen. Then 

 comes a winter with exceptionally heavy snowfall 

 and with storms of ice and sleet that prevent the 

 birds from securing food, when the little colonies at 

 the outposts die of starvation and the ground gained 

 by generations is lost in a single season. Only the 

 hardiest individuals survive and it is their progeny 



