WEHTEMN MOURNING DOVE 597 



At the beginning of the breeding season, which is announced by 

 the augmented cooing of the males, the flocks break up and the birds 

 scatter out, each pair ordinarily nesting by itself. At times, however, 

 several couples may nest in such close proximity to each other as to 

 suggest a colony (Tyler, 19136, pp. 35-37) ; but their behavior is 

 quite different from that of strictly colonial birds. Nests are to be 

 found in all sorts of locations, and it is difficult to infer any choice 

 of situation on the basis of seclusion, protection from enemies, or even 

 proximity to food or water. They are found on the bare open ground, 

 on the banks of gullies, in low bushes, and at varying elevations in 

 trees, some having been noted as much as forty feet above the ground. 

 Probably six or eight feet would be an average height for nests that 

 are built above the surface of the ground. Whatever the location, 

 the structure is crude, a mere platform of small sticks and grasses 

 or roots, so loosely put together that in elevated nests the eggs may 

 often be seen through the structure from below. Sometimes the 

 deserted nests of other birds, as for example of the mockingbird 

 (Tyler, loc. cit.), may be used, and slightly added to; but this prac- 

 tice is not common. 



Nests of the Mourning Dove rarely contain more or less than two 

 eggs. Tyler (loc. cit.) states that after "examining hundreds of nests" 

 he can only recall two in which the complement deviated from that 

 number. One contained three eggs, one of them being so different 

 that he believed it to have been deposited by another female ; the 

 other held a single heavily incubated egg in a remodeled mocking- 

 bird's nest. The unusual depth of the latter nest made it unlikely 

 that a second egg had been present and had rolled out. A. K. Fisher 

 (1893a, p. 33) states that at Lone Pine, Inyo County, a nest was found 

 during the first part of June which contained three young. 



According to Bendire (1892, p. 142), one day intervenes between 

 the deposition of the first and second eggs, and the process of incuba- 

 tion is said to last for about two weeks. Our impression is that 

 incubation is carried on by the female only. If a nest is approached 

 the sitting bird may slip quietly off and fly away some distance ; or, 

 again, the " broken- wing " ruse may be tried in its extremest mani- 

 festation. Probably, as with other birds, this ruse comes into use 

 chiefly towards the end of the period of incubation. 



The eggs are elliptical ovate, that is, more nearly equal-ended than 

 those of the domestic hen, and are pure white in color, with a slight 

 gloss. They vary considerably in size ; thirteen sets (twenty-six eggs) 

 in the Museum of "Vertebrate Zoology measure in inches, 0.98 to 1.23 

 by 0.77 to 0.87, and average 1.07 by 0.83. The eggs of the Mourning 

 Dove differ from those of the Band-tailed Pigeon in being decidedly 

 smaller, about two-thirds as long and one-third the bulk. It is com- 



