200 Saunders, An Ecological Bird Study. [April 



AN ECOLOGICAL STUDY OF THE BREEDING BIRDS OF 

 AN AREA NEAR CHOTEAU, MONT. 



BY ARETAS A. SAUNDERS. 



The subject of the ecological associations of various forms of 

 life has recently been given considerable attention. Most of the 

 studies that have been made along this line, however, have been 

 of plant life. Such studies of animal life, and particularly of bird 

 life, have been comparatively few. This is probably because 

 animals, and particularly birds, can move about from place to 

 place, and are consequently less closely related to any one ecological 

 association. In the breeding season, however, birds are fairly 

 stationary, remaining in the vicinity of their nests. At this time 

 they are confined to certain associations, which evidently depend 

 on the character of their food and the locality chosen for their 

 nesting sites. Sometimes a given species is confined to a single 

 association and makes up a component part of its life. At other 

 times a species may be found in several different associations, and 

 may be less common in one than another. Occasionally a species 

 nests in one association, but obtains its food largely in another. 

 The study of these associations and the proportionate abundance 

 of the different species of each is not only of great scientific interest, 

 but also has an important bearing on the problem of obtaining an 

 accurate census of our birds, and on the problems of the preserva- 

 tion of wild life. 



In forestry, the study of the forest types, which is merely a 

 simpler name for an ecological association of forest trees, is of great 

 importance. In my work with the United States Forest Service 

 in Montana, I was frequently called upon to study and map these 

 types. Through this work I obtained a closer insight into these 

 associations and their relations to other forms of life. In the local 

 lists of birds which I have published for the different parts of Mon- 

 tana where my work has been located, I have attempted to describe 

 the more important associations and list the species breeding in 

 each. I have always hoped, however, for an opportunity to make 

 a deeper study of these associations, showing the proportions of 



