Bird Architecture 



HOW THE YELLOW WARBLER OUTWITS 

 THE COWBIRD 



There are still many lazy, slovenly, indifferent, 

 commonplace or utilitarian home makers among 

 undeveloped or degenerate birds as among humans, 

 but happily only one of our birds disgraces itself, like 

 the European cuckoo, by refusing to make a home 

 and to perform any domestic duties whatever. When 

 other virtuous nest builders are working and singing 

 from morning till night, the cowbird, a dark, silent, 

 decadent relative of those charming songsters, the 

 oriole, bobolink and meadowlark, skulks about alone, 

 >:lyly looking for the chance to drop an egg in the 

 nest of some little warbler or vireo — any small, weak, 

 tender-hearted foster-mother she can lind — leaving 

 to various such victims the labour of hatching and 

 rearing her scattered brood. A serious task indeed 

 awaits the over-burdened little mother who must 

 feed a great gaping gourmand in the cradle with 

 her own crowded and half-starved babies. 



But there is at least one ingenious little architect 

 among the cowbird's special victims whose wits fre- 

 quently save it from such misfortune. Finding a 

 strange egg in its cup-shaped nest and being unable 

 to roll it out, the yellow warbler proceeds to weave 

 a new bottom, effectually sealing up the cow-bird's 

 egg and preventing the heat from her brave little 

 heart from warming it into life. Suppose this '* wild 

 canary," as it is often called, had already laid her 

 own eggs in the nest at the time of the cowbird's 

 visit : what then ? In this case the warbler does not 

 hesitate to sacrifice them, sealing them up with the 

 cowbird's by weaving a new bottom above them, 



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