30 BIRDS OF SOUTH DAKOTA 



splashed; while the Meadowlark, our lighter colored Starling, 

 has an ideal egg, with clear ground color and exquisite brown 

 spots. 



This line of reasoning cannot be followed far, however, 

 without becoming inextricably tangled with the problem of pro- 

 tective coloration; for example, the eggs of the Catbird, Robin 

 and Wood Thrush, while varying in shade, are greenish blue, 

 while the birds themselves are very differently colored. 



Notwithstanding exceptions, there would seem to be a 

 good deal of protective coloration in the shading and spotting of 

 eggs. The greenish blue eggs just mentioned are difficult to see 

 in the shade of trees and bushes where the nests are placed. All 

 eggs that are spotted and splashed are protected thereby in the 

 dappled lights and shadows that play over them when uncovered 

 in the nest. Most birds that nest inside of holes, such as Wood- 

 peckers, have white eggs; but exceptions at once occur in the 

 exquisite brown egg of the Wren and the delicate blue egg of 

 the Bluebird. It will be noticed that these fall under the other 

 rule, that of the color of the birds themselves. 



The Mourning Dove's pure white eggs, laid on a slender 

 scaffolding of roots and exposed to the sight of every nest rob- 

 ber in the woods, are a glaring exception to color protection ; and 

 the exception is more marked when we remember that the Dove 

 offers no defense of its eggs, except to flutter away as though 

 wounded to lure the intruder from its treasures. The Mourning 

 Dove's nest is probably rifled more than any other nest in the 

 woods, but this is compensated for by the fact that the Dove 

 breeds almost continuously throughout the season. They have 

 been found brooding eggs in September. 



Most Hawks' eggs are white or cream color, sometimes 

 with spots, but they are able to defend them. 



Some colors are not only for defense but also for offense. 

 Owls are noted for protective coloration, doubtless not so much 

 for their own defense as to allow them to approach their prey 

 unobserved. The Snowy Owl changes color with the seasons, 

 becoming nearly white when the ground is covered with snow. 



