662 BULLETIN 203, UNITED STATES NATIONAL MUSEUM 



It requires a week or ten days for the industrious female to build 

 the nest. The task is performed in a most expert manner. The out- 

 side framework is first constructed, and then she enters the nest to 

 adjust the lining, turning around and around and pressing her breast 

 against the sides until the desired symmetry is attained. The final 

 bits are dextrously manipulated by the bird's bill and seem to be 

 pasted on, according to various observers, with the aid of her own 

 saliva. 



Louis Sturm (1945) observed the building of one nest, which he 

 states was completed in the course of 21/2 to 3 days. He estimated 

 that the bird made 650 to 700 trips in building the nest. The first 

 egg in this case was laid 2 days after the completion of the nest. 



William Brewster (1936) presents a detailed account of the build- 

 ing of a redstart nest that is interesting and informative : 



At about 6 A. M. on May 17th a female redstart brought a long, transparent, 

 silky-looking fiber — apparently that of a milkweed stalk — to a gray birch in 

 front of the cabin and, placing it at the intersection of a rather stout branch 

 with the main stem, began moving it about until its position suited her, when 

 she pressed it down firmly by rubbing it with the side of her head which she 

 turned slowly from side to side. This was literally the first bit of nest material 

 that was put into the crotch. Many others of an apparently similar kind were 

 brought during the forenoon and treated in the same way, although the bird 

 had to use her bill rather vigorously in tamping some of the more refractory 

 ones into place. She worked busily and steadily until noon when the foundation 

 of the nest was finished. 



At about 2 : 30 P. M. she began the frame by attaching one end of a strand of 

 fibrous material to the right hand side of the trunk a little above the branch 

 on which the foundation was laid and fastening the other end to the foundation 

 on the same side, the strand inclining downward at an angle of about 30° or 40°. 

 Next, another strand was placed on the left side in the same position as the 

 first, the ends of the two overlapping on the trunk. Then a third piece was 

 brought and one end rubbed lightly against the center of the strand on the right, 

 the opposite end being carried a little beyond that of the left hand strand. Next 

 a fourth strand was rubbed on the trunk a little above the upper end of the left 

 hand guy, to the middle of which the opposite was fastened by rubbing the two 

 together. Each piece of fiber was fashioned into the general shape of the nest as 

 soon as it was attached to both ends and more were brought and carried from 

 point to point until a complete framework of about the size and shape of the 

 half of a hen's egg was erected around and resting on the foundations. This 

 framework was so delicate that it looked as if the merest breath of wind would 

 blow it away. During its construction, the bird worked entirely from the 

 outside, standing on the branch and shaping each piece of fiber with her head. 



The next day (May 18th) she began using cocoon fibers as well as milkweed 

 bark. The former she obtained from a groove near the top of the cabin door 

 in front of which she would hover on rapidly vibrating wings until the exertion 

 compelled her to alight for a moment to rest and regain breath, either on top 

 of the door or its hand knob. As soon as she had filled her bill, she would fly 

 to the birch, alight on the branch and distribute her load around the inside 

 of the nest; then, hopping into it and squatting down with her head and tail 

 raised and back deeply hollowed, she would move slowly around to the right 



