BIRD BIOGRAPHIES 



gard for their own young. They are like the human 

 mothers who lay their babies on doorsteps, depart, and 

 let others rear them. 



It is a well-known fact that the female cowbird always 

 selects the nest of a bird smaller and weaker than herself 

 in which to deposit her egg. Major Bendire lists ninety- 

 one varieties of birds that have been thus outraged, fre- 

 quent victims being the song sparrow, indigo bunting, par- 

 ula wa,rbler, yellow warbler, vireo, chipping sparrow*, 

 towhee, oven-bird, yellow-breasted chat, and even the tiny 

 blue-gray gnatcatcher. From one to seven cowbirds' eggs 

 have been found at a time in other birds' nests, often in 

 the warm center of the nest. Unless the little bird should 

 build a new floor, or abandon her nest entirely, the cow- 

 bird egg will hatch first, and the lusty changeling will de- 

 mand the lion's share of food and attention. Frequently 

 the other eggs do not hatch; if they do, the young birds 

 often perish with hunger and cold. When young cowbirds 

 have been reared by their patient little foster-parents, they 

 leave their benefactors and join flocks of their disrepu- 

 table relatives. 



In justice it must be said that cowbirds, like all villains, 

 have a redeeming trait — they are great destroyers of weed 

 seeds and insects. Like Cadmus and his band, they "Fol- 

 low the Cow," and enjoy the insects that she arouses as 

 she walks about in pastures. When the cow lies down, 

 they, too, pause; they have been known to hop upon her 

 back in friendly fashion. Self-interest prompts them, 

 however, for they know that they may find there a harvest 

 of insects. 



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