THE OOLOGIST 



69 



History of a Double Nest 



of the Yellow Warbler. 



While climbing over a fence, one 

 day in May 1S99, I noticed in a Wild 

 Rose bush at ray feet a nest of the 

 Yellow Warbler. It was placed about 

 three feet from the ground and some 

 ten cr twelve feet from the shore of a 

 small pond and appeared to be com- 

 pleted, but held no eggs. 



Passing by the spot again at noon 

 on the 17th I glanced into the nest 

 and saw one egg of the Cowbird, but 

 none of the rightful owners. Curious 

 to see how the Warblers would treat 

 this intrusion into their home I return- 

 ed at 1:30, but the egg was nowhere 

 in sight. Closer examination showed 

 that a thin layer of plant fibres had 

 been laid over the egg; in fact the be- 

 ginning of a second nest. The birds 

 must have worked very rapidly to 

 have secured enough material to en- 

 tirely conceal the egg in so short a 

 time, but during the rest of the after- 

 noon I watched them at their nest 

 building and found they worked con- 

 tinuously without resting. 



Procuring some soft cotton, I fas- 

 tened it to the twigs of a nearby bush 

 and retired to a tangle of Wild Grape- 

 vine to watch. Hardly had I conceal- 

 ed myself when the male appeared and 

 sang from a sappling just over the 

 nest. The female appeared a moment 

 later and flew directly to the cotton, 

 fluttering before it and tearing off lit- 

 tle tufts which were woven, or rather 

 matted into the nest. At no time did 

 the female alight to tear off the cot- 

 ton, but on each trip poised in the air 

 before it, much as a Hummingbird 

 does in front of a flower. Generally 

 three or four strips were carried to the 

 nest each visit. 



Arriving at the nest with a beakful 

 of cotton the female settled down into 

 the nest, turning around and tucking 

 in little bits here and there, shaping 



the sides and rim with her breast and 

 bill, and matting the whole into a 

 solid feltlike substance. No time was 

 wasted at the nest however, and in a 

 few minutes she was back after more 

 material. 



While the female was thus busily 

 employed, the male flitted from bush 

 to bush, caught an insect here and 

 there, sang, now in the trees overhead, 

 now from the bushes near the nest, 

 but only once or twice did he visit 

 the nest. On these visits he did not 

 appear to be carrying any material 

 for the nest. It was probably simply 

 a tour of inspection and as if satisfied 

 with the way the work was progress- 

 ing he finally disappeared and it was 

 nearly an hour before he canae back, 

 announcing his return by singing in 

 the trees overhead before descending 

 to his mate in the bushes below. 



By sunset the second nest was to all 

 appearances completed, but when I 

 visited it again next morning I found 

 that the birds had worked in a quan- 

 tity of buff colored vegetable fibres, 

 not materially increasing the bulk of 

 the nest, but toning down the white- 

 ness of the cotton and rendering the 

 structure much less conspicuous than 

 it had been the night before. The nest 

 was now complete and a vacation of 

 several days followed before the eggs 

 were laid. Had the birds been com- 

 pelled to procure their nesting ma- 

 terial in the regular way instead of 

 having a supply so conveniently fur- 

 nished them, the building of this sec- 

 ond nest would doubtless have taken 

 much longer. 



The first egg was laid May 23d and 

 one was deposited each succeeding 

 day until four had been laid. Incu- 

 bation began at once and lasted ten 

 days, the young appearing on the 5th 

 of June. For the first few days their 

 growth was rather slow, but both 

 parents fed them constantly, the fath- 



