COWBIRD; COW BLACKBIRD, ETC. 157 



crowds either the unhatched eggs or the little birds out 

 of the nest and appropriates all the food the busy little 

 foster-parents can provide. (Fig. 79.) 



When the female Cowbird slyly steals through the 

 underbrush and stealthily deposits her egg in the nest 

 of the little Vireo, or the Yellow Warbler, and abandons 

 it, she knows by some mysterious instinct that her egg 

 and its future young will be amply provided for by the 

 foster-parents. When the time comes for the Cowbird 

 to lay her egg she does not feel the home-building im- 

 pulse, or at least does not respond to it. Why bother 

 about anticipated maternal duties by building a nest, or 

 changing plumage, or pressing the male into the car- 

 pentry or plasterer 's trade, when all these duties may be 

 performed by others? 



The Cowbird, to me, always has a peculiar sheep- 

 dog, sneaking demeanor, with nothing dignified, assertive 

 or pugnacious to be seen in its actions. Watch the fe- 

 male as she sneaks to the branches near the ground in her 

 quest of some nest to despoil with her egg. Her every 

 action is that of a thief, or eavesdropper. She does not 

 protest your presence in that locality. In fact, she seems 

 to say, by her actions, that you have more rights near a 

 bird's nest than a Cowbird has, and I fully agree with 

 her on that point. 



Unless I desire to observe the rearing of the young 

 Cowbird by its foster-parents, I always remove the egg 

 from the nest with a little stick, as the Vireo and other 

 birds often abandon the nest if you touch their eggs with 

 your fingers. 



Cowbirds are good nest-finders. But on some oc- 

 casions the small bird refuses to assume additional forced 

 parental duty and builds a false floor in the nest to cover 

 the Cowbird 's egg. She then lays her own eggs on the 

 new nest-bottom and thus thwarts the endeavors of the 

 slacker. 



The Yellow Warbler often resorts to this procedure. 

 One day in July, while looking for nests and birds to 

 photograph, I saw a slacker come up from the weeds 

 and underbrush to a low limb. Her every expression was 

 that of a sneak ; her every movement was that of a traitor 

 and a coward. I was satisfied that there was, in that 

 vicinity, some bird's nest which she had been despoiling 



