28 BIRDS OF SOUTH DAKOTA 



PROTECTIVE COLORATION 



In studying birds one must ignore the females. This 

 would be a rather unsafe policy in studying human beings, 

 but among birds it is necessary because the males are the 

 singers and wear the bright colors, while the females do not 

 "shine" either in music or dress. One learns the females easily 

 because they are the companions of the males during the mat- 

 ing season. But for this fact the study of female birds would 

 be a very difficult task, for most of them have sober colors, 

 and the females of many species resemble each other. For ex- 

 ample, it is not easy to distinguish the females of several dif- 

 ferent Blackbirds, or of numerous Sparrows. Of course in 

 some species males and females are alike, but bright colored 

 males and sober colored females is the general rule. 



The colors of male birds are always the brightest in 

 the mating season, as though for the purpose of being attrac- 

 tive to the females. Some have thought that the most attrac- 

 tive males won the females, and then, reproducing their kind, 

 developed in the species increased attractiveness. Others have 

 thought that beauty in males was connected with strength and 

 virility, and that stronger males won the females because of their 

 prowess in driving off other suitors. 



It is difficult to decide such matters, but it seems cer- 

 tain that in the modest colors of females nature has made care- 

 ful provision for the protection of the mother on her nest. The 

 dappled brownish black of female Red-winged and Yellow- 

 headed Blackbirds blends perfectly with the varying light and 

 shade that play over their nests from the tops of flags and 

 rushes swaying above them. 



The female Rose-breasted Grosbeak is about the color 

 of the materials of which she builds her nest, and the colors 

 of both herself and her nest are not unlike the color of bark. 

 The male Scarlet Tanager is like a burst of flame in the forest, 

 but his mate has the color of green leaves, and when on her 

 nest can scarcely be seen. 



Birds of prowess, like Blue Jays, Crows and Hawks, 

 show little difference in color between males and females. 



