BIRDS OF THE ST. CROIX RIVER VALLEY 



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Fig. 5. Location of major Christmas Bird Count areas in the St. Croix River Valley. 



Accidental— A species that is not expected to occur again or that occurs 

 very infrequently. 



Hypothetical— A species that probably occurred in the Valley at least 

 once, but the circumstances of the observation leave the record in 

 doubt. 



Introduced— A species that is naturally foreign to this region but has been 

 released in the area as an act of man and is now established and repro- 

 ducing without additional influence by man. 



Extirpated— A species that once occurred naturally in the Valley, has now 

 been eliminated, but still exists elsewhere. This term applies to both 

 migrants and nesting species. 



Extinct— A species that no longer exists anywhere on earth. 



The population status of several species has recently become a concern of 

 the public. Legal protection for all birds except the rock dove, starling, and 



