PREFACE 



Effort has been made in this bulletin to obtain as com- 

 plete a list of South Dakota birds as possible. In all, 322 species 

 and subspecies have been recorded. With few exceptions these 

 are represented in the University Museum collections at Ver- 

 million. 



There is perhaps no State in the Union where bird study 

 is more perplexing than in South Dakota. From east to west 

 the State embraces birds of woods, prairie and mountains. The 

 range of many birds is constantly moving westward, and this 

 causes variation in the migrating routes of many species. The 

 Black Hills, lying only a little apart from the Rocky Mountains, 

 are apt to be visited occasionally by western species. 



From south to north, likewise, both trees and latitude 

 affect the bird problem. The Missouri River with its wooded 

 banks and ravines, traversing the middle of the State, provides 

 conditions which attract some species farther north than they 

 would otherwise come. But for this fact we probably would not 

 have the beautiful Western Blue Grosbeak within our borders. 

 Birds from farther east and south also, such as Cardinals and 

 Wood Thrushes, follow the growing trees into South Dakota. 

 Many birds are found in the southern part of the State which 

 are never seen in the northern part ; and some birds which form- 

 erly nested in South Dakota no longer do so. 



So numerous, therefore, are the changes going on in bird 

 life within the State that observations which were made a few 

 years ago may not be accurate today and observations made to- 

 day may not be accurate tomorrow. 



The authors desire to acknowledge their indebtedness 

 particularly to the late Dr. Elliott Coues and to Mr. Frank M. 

 Chapman, with whose works their own observations have been 

 diligently compared; and to Mr. H. C. Oberholser and Mr. A. 



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