The prairie falcon has been classified as threatened species by the U.S. 

 Fish and Wildlife Service (1973), although this classification is no longer 

 being used. This bird was seen at all seasons in the vicinity of the mine study 

 area, and is believed to occur as a permanent resident. Watering birds probably 

 rely heavily on the abundant horned lark as a prey item. A nest was discovered 

 approximately 100 m (328 feet) north of the northern boundary of the proposed 

 mining area, and contained four eggs when visited in 1977. Most of the proposed 

 mining area was within the hunting territory of this pair, and the adults were 

 frequently seen along Nelson Creek or perched in the cottonwoods in Section 32. 



Other Rare and/or Unique Species 



The burrowing owl has been included in the 1977 "Blue List" (Arbib 1977) 

 and has also been classified as "Status Undetermined" by the U.S. Fish and Wild- 

 life Service (1973). It appears to be undergoing a widespread population decline 

 (Flath 1978, Zarn 1974). Although no nests were found in the mine study area, 

 several birds were seen during this study. 



The ferrugious hawk, mentioned above, is also relatively rare and nests 

 within the mine study area. A single capture of a Merriam's shrew was made 

 during this study. While wery few specimens of this mammal have been taken in 

 Montana, it is probably not as rare as the paucity of records would indicate, as 

 inadequate trapping effort has been expended. Other status-undetermined or "Blue 

 List" species are indicated in tables 7 and 8. 



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