114 STATUS OF THE SPECIES 



Species which are the direct object of man's unbridled greed, must 

 succumb to an enemy before which neither swiftness of flight nor exces- 

 sive wariness avail. Thus the Wild Pigeon and White Egrets, however 

 well they were fitted to contend with nature, could not escape man. 



But when man enters the bird's life only indirectly, altering its 

 environment without actually killing the bird itself, the species in 

 undiminished numbers is left to face the problem; and its ability to 

 adjust itself to new conditions is now put to a vital and immediate test. 



The Pileated and Ivory-billed Woodpeckers have decreased with 

 the forests; but the Crow and the Robin, both naturally forest-inhabit- 

 ing species, have more than held their own. Both, in different ways, 

 have adapted themselves to the new order of things; the Crow meets the 

 distinctly hostile if not actively aggressive attitude of man by wariness 

 and more than average intelligence; the Robin, through its fearless- 

 ness, has won man's friendship and protection. Near his dwellings its 

 natural enemies have been reduced in number, and the normal food 

 supply greatly augmented by fruits of various kinds, a more accessible 

 supply of worms on close-cropped lawns, and various insects which 

 also thrive on man's bounty. 



The introduction into this country of the House or English Sparrow 

 has, from a biological point of view, been an overwhelming success. 

 Not only did the bird fill an unoccupied place in our cities, but when 

 brought into competition with native species, its hardiness, general 

 adaptability, pugnacity and continuous presence have all been in its 

 favor. When the migratory Bluebirds or Purple Martins returned, they 

 often found the Sparrows in possession of their nesting-boxes, and the 

 decrease in the numbers of both these species is unquestionably to be 

 attributed to their inability to compete with the Sparrow. 



In the changes wrought by man, directly or indirectly, we may 

 find many similar illustrations of sudden alterations in the bird's 

 environment, and the manner in which they are met demonstrates what 

 is meant by adaptability. In nature, equally great changes may occur, 

 but they take place more slowly, and the adjustment between them and 

 the bird, while not the less essential, is not so severe and sudden a tax 

 on the bird's resources. 



But aside from these external influences, which may remain un- 

 changed and hence inactive for long periods of time, there are certain 

 internal influences which are constantly potent. Chief among these is 

 temperament as it is expressed in sociability or desire for solitude. It 

 is obvious that only birds of social, or at least peaceable, disposition 

 could live in such close juxtaposition as do colonial birds, like Gannets, 

 Murres, Flamingoes, Cliff Swallows and many others, where nests or 

 nesting birds almost touch one another. Such social species are usually 

 represented by numerous individuals, while on the other hand the 

 relative abundance of solitary species is related to the extent of the 

 area over which they claim guardianship while nesting, to the exclusion 

 only of other birds of their own kind. Hence, Hawks and Owls, for 



