Mines which appeared to have the best potential for current bat use included the 

 Bluewing, Clipper, Hendricks, Huron/Cottontail, Keystone, Shoemaker, and an unnamed 

 cluster of shafts near the Watseca mine. These mines were extensive with complex 

 workings that may interconnect underground, facilitating air flow through the mine. 



The locations of mines found in reports or databases were generally imprecise and given 

 in Township, Range, Section and quarter-quarter-quarter section format. In areas with a 

 high density of mines and mine openings, it was sometimes difficult to know for certain 

 which mine was examined. We also identified discrepancies in land ownership indicated 

 in databases and reports. In some instances, it was not clear if the land ownership at a 

 mine was BLM, mixed BLM-private, or private. Time will be spent at the Montana 

 Department of Environmental Quality (MT DEQ) during the up-coming months to sort 

 out land ownership discrepancies to ensure that only mines on public lands are sampled. 



Potential for human entry into mines 



Many of the mine openings visited appeared to be unstable and potentially unsafe for 

 human entry. Adits and shafts were often partially collapsed. Mine openings in the 

 Rochester Mining District seemed to be more unstable than elsewhere. The surface rocks 

 in this area consist mostly of oxidized shists that are very friable (primarily the Emma, 

 Cooper, Shoemaker mines, and mines in the vicinity of the Watseca mine), while the 

 Clipper mine was situated in gneiss rock and appearded to be somewhat more stable. 

 Mines in the Bannack Mining District were often located in limestone substrate. 

 Openings in this area appeared to be more stable and amenable to internal survey. The 

 Bluewing, Huron/Cottontail, and Hendricks mines probably have the highest potential for 

 internal surveys. 



Human entry into abandoned mines wil require very specialized training. We intend to 

 meet this winter with personnel fi-om the BLM, MT Bureau of Mines and MT 

 Department of Environmental Quality to identify a team of specialists that is capable of 

 evaluating mines for safe entry and conducting internal surveys. 



External survevs 



External monitoring for bat activity was conducted at 66 mine openings fi-om 34 mines 

 (Table 1). (Not all mine openings were monitored.) In all but three cases, monitoring 

 was conducted to sample bat activity only at a specific mine opening. Mine openings 

 were sampled for one night only, with the exception of the Kent-Bluewing and Ermont # 

 1 9 mines, which were sampled on two occasions (late August and late September). 

 Ultrasonic monitoring occurred at 59 openings, while mist netting was conducted at eight 

 locations. A cursory review of tape recordings from ultrasonic monitoring and the mist- 

 netting documented bat activity at openings of at least 24 mines. 



The analysis of tape recordings from ultrasonic surveys is in progress, with eleven tapes 

 having been analyzed to-date. Tentative bat species detected by ultrasonic methods 



