VALUE OF BIRDS TO MAN. 81 



Xavigators approaching their home port during seasons 

 of bird migration welcome the appearance of familiar land 

 birds which are seen while land is still far out of sight. Mr. 

 Frank M. Chapman has shown, in an interesting paper on 

 the ornithology of the first voyage of Columbus, that we 

 possibly owe the discovery of America by Columbus to the 

 fiict that he happened to approach the land at the right time 

 and place to cross the line of the fall Hight of land l)irds that 

 were going from the Bermudas to the Bahamas and Antilles. 

 The discouraged seamen were on the verge of mutiny, and 

 might have compelled Columbus to return to Spain, had not 

 small land birds come aboard unwearied and singing. The 

 course of the vessel was changed to correspond with the 

 direction of their flight, and the voyage was thus shortened 

 two hundred miles and pursued to its end.^ 



The well-known services of Vultures, which destroy gar- 

 bage and carrion in the tropics, have no real counterpart in 

 the north. Crows are of some use, but Gulls and other 

 water-birds are most valuable to man in this respect, in that 

 they devour the garbage and refuse that are cast into harbors 

 and arms of the sea, thus undoubtedly preventing the pollu- 

 tion of many bays and beaches by floatino- filth and refuse 

 from great cities. 



Sea birds must be reckoned among the chief agencies which 

 have rendered many rocky or sandy islands fit for human 

 habitation. The service jierformed by birds in fertilizing, 

 soil-building, and seed-sowing on many barren islands has 

 entitled our feathered friends to the gratitude of many a 

 ship^vrecked sailor, who must else have perished miserably 

 on barren, storm-beaten shores, 



THE COMMERCIAL VALUE OF BIRDS. 



In all the foregoing we have considered mainly "the good 

 offices that birds voluntarily take upon themselves in our 

 service." We have yet to take into account the tax which 

 we impose upon them for our own revenue of profit or 

 pleasure, — a tax which we collect unsparingly, and with the 

 strong hand of force. 



^ Papers presented at the "World's Congress on Ornithologj', 1896, i^p. 181-185. 



