174 YEARBOOK OF THE DEPARTMENT OF AGRICULTURE. 



towns its colonies are so large that the resulting damage it inflicts 

 upon fruit trees in spring is very great. It is fond also of all the 

 small fruits, and in some regions the damage to fruit as the result 

 of its attacks is considerable. 



There is yet another field for the exercise of this pest's pernicious 

 activity. Its aggressive and meddlesome disposition and its habit 

 of acting in concert enables it to overpower and drive away many of 

 our native birds, which before its advent were as numerous about 

 dwellings as they were welcome. 



The house wren, the bluebird, the phoebe, and certain swallows are 

 the chief sufferers from the aggressive warfare waged by the sparrow. 

 Even that excellent fighter, the purple martin, is unable to long resist 

 the persistent attacks of a united colony of sparrows, since, when 

 unable to overcome the martin in open warfare, the sparrows enter 

 the nests during the absence of the owners, kill the helpless young, 

 and pitch out the eggs. The result is that not only are the above- 

 named species and other small birds driven away from the localities 

 they used to inhabit, but their numbers have steadily diminished and 

 must continue to do so because of their inability to find other suitable 

 breeding places. Thus the sparrow has usurped the places about our 

 homes by right belonging to our own birds, and its increase has 

 been at the expense of native American species, with the result that 

 a number of highly important useful species have been replaced over 

 large areas by a single destructive one. Not only should all aid and 

 comfort be withheld from this foreign invader, but a concerted effort 

 should be made to reduce its numbers and to exterminate it wherever 

 and whenever possible. 



CRANES AND HERONS. Some of our birds are neither insect eaters 

 nor vegetable eaters. Some of the hawks and owls, as is well known, 

 live chiefly upon flesh, while the cranes, herons, storks, and king- 

 fishers live largely upon fish, crustaceans, and frogs. By eating 

 small fish which are the fry of valuable kinds or serve as their food, 

 these birds do more or less harm, as the fish breeder, whose ponds are 

 invaded, knows well enough. So also their habit of eating frogs is 

 injurious. 



But while thus injurious to some extent in certain localities where 

 their pernicious activity may necessitate reprisals, cranes and herons 

 do good service in the destruction of small rodents, especially meadow 

 mice and pocket gophers. As in other cases the relation of these 

 birds to the community varies according to circumstances, and they 

 are to be dealt with accordingly, bearing in mind, so far as possible, 

 the good to the community as a whole and not solely individual 

 interests. 



