The Birds' Calendar 



up another partner with surprising and almost 

 unseemly celerity. 



A bird's natural period of life appears to be 

 somewhat, though by no means strictly, pro- 

 portional to its size. Vital statistics of such 

 fugacious creatures are difficult to obtain, and 

 afford only approximate conclusions. It is 

 known, however, that eagles and swans some- 

 times live a hundred years, whereas, for many 

 of the smallest species the limit is only five 

 or six years. Peacocks not uncommonly live 

 twenty years, and even goldfinches and black- 

 birds have attained that age, although probably 

 it is greatly in excess of their natural limit ; and 

 parrots have survived sixty years in confine- 

 ment. Doubtless, the average duration of bird- 

 life, as fixed by nature, does not exceed ten or 

 twelve years. 



Yet, naturally short-lived as are the great 

 majority of birds, vast numbers are prematurely 

 cut off by adverse climate and lack of food, by 

 the ravages of disease, by the attacks of numer- 

 ous insidious foes among the lower animals, 

 and, most lamentable of all, by the wanton as- 

 saults of man himself. It is disgraceful to hu- 



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