Notes from Field and Study 



179 



To Hatch and to Raise 



Somewhere near the middle of June, we 

 discovered that a pair of Yellow Warblers 

 had chosen to build their nest in a syringa 

 bush close to our living-room window. 

 Here was an opportunity to watch a bit 

 of bird-life without leaving the house. 



The three eggs were hatched out June 30. 

 By the next afternoon one of the young 

 birds appeared larger than the others. 

 Another day, and there was no doubt 

 about it; the difference was obvious. No 

 wonder, for this greedy individual hardly 

 permitted the others to be fed at all. 

 Toward evening, on July 2, one of the 

 three, which had remained a little, throb- 

 bing lump of pink flesh, ceased to lift its 

 head when the mother bird came to the 

 nest. 



Up to this time, I had accepted the 

 larger individual as a young Yellow War- 

 bler, but it now dawned on me that it was 

 a Cowbird. And this became more evident 

 as the disparity in size between the two 

 remaining occupants of the nest became 

 more marked. One could almost see the 

 Cowbird grow, and as it grew, it more and 

 more completely dominated the food- 

 supply. 



July 4 was a hot day, and the Cowbird 

 was restless. The nest was now hardly 

 large enough to hold both it and the 

 Warbler, and the latter was badly crowded 

 and maltreated as its big nest-mate moved 

 around in the narrow quarters. 



So matters continued until the forenoon 

 of July 5, when the Warbler was several 

 times almost, and then quite, crowded out 

 of the nest by the Cowbird. It managed, 

 however, to hang to the nest by what, in 

 the case of a human being, would be the 

 chin, and after a lively struggle, succeeded 

 in getting into the nest again. But it 

 appeared to be utterly exhausted. The 

 struggles of the little fellow were too much 

 for my scientific attitude; I concluded to 

 take a hand. Securing a Warbler's nest of 

 the previous year, I fastened it to the bush 

 a foot below the original nest. Into this 

 I put the Cowbird, leaving the young 

 Warbler in the old nest. 



The adult Warbler came to the old nest, 

 fed its one occupant, and seemed not the 

 least disturbed by the absence of the other. 

 In this way the young Warbler was fed 

 four times without interference from the 

 Cowbird. When the adult came the fifth 

 time, the Cowbird made such a commotion 

 that its foster mother was attracted to it. 

 Thereafter she went each time to both 

 nests, but always to the old nest first. The 

 Cowbird, however, was so loud and insistent 

 in its demands for food that often the 

 mother bird would stop in the very act of 

 offering food to the Warbler and take it 

 down to the Cowbird. That night she 

 covered her own offspring. 



A week after being hatched out, July 6, 

 the Cowbird was larger than the adult 

 Warbler, and the nest was being spread all 

 out of shape by it. The young Warbler, 

 on the contrary, was showing signs of 

 weakness, at first only listlessly reaching 

 for the proffered worm, and then paying 

 no attention to it whatever. The mother 

 bird was obviously disturbed. Going to 

 the nest with a worm or gnat in her bill, 

 she would chirp several times, waiting for 

 it to be accepted. The young Warbler 

 remaining motionless, she would then feed 

 the Cowbird, but return immediately to 

 the old nest, and occasionally settle herself 

 for a little time on the little Warbler 

 before she flew off again to the hedges. In 

 the afternoon a shower came up, and she 

 sat on the nest until it was over, a feathered 

 epitome of solicitude. Nothing, however, 

 availed. When, after the shower, she came 

 again with food, the occupant of the old 

 nest was beyond the want of it. Until well 

 into twilight she fed the Cowbird, continu- 

 ing, however, to go to the other nest first, 

 and after dark she protected the little 

 dead Warbler from the night air. 



The next day, July 7, she devoted her- 

 self entirely to the Cowbird which now 

 sprawled over the top of its distorted nest. 

 Nor did she any longer go first to her own 

 nest. Only occasionally, before flying off 

 again for more food, would she hop up 

 and examine the nest and the dead bird. 

 And that night she slept away from home. 



On the 8th she was on hand early, and 



