Elkhorn 



One night was spent listening for bats around old mine 



buildings 1/2 mile north of the townsite of Elkhorn in the 



Elkhorn Mountains. No evidence of bat activity was 



recorded. 



An attempt was made to locate some reported mine sites west of 

 the mouth of Foster Creek west of Anaconda, but these could not 

 be located. No other mine sites were surveyed on the Deerlodge 

 National Forest in 1992. 



DISCUSSION 



Survey methods 



A study designed to determine absolute and quantitative abundance 

 of a species is a census. Several methods, such as mark- 

 recapture and visual counts (Thomas and LaVal 1988), have been 

 used by researchers to estimate absolute bat numbers, but these 

 have generally been in enclosed areas such as caves, or at 

 specific roosting or maternity sites. Determining quantitative 

 measures of bat densities in a given habitat or foraging within a 

 given area is not considered possible with current technology 

 (Findley 1993, Thomas and West 1989). 



A survey is designed to provide relative and qualitative 



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