information, in short to "respon(d) to such questions as. Does 

 habitat A have more bats of a given species than habitat B does? 

 or Is species X more abundant before or after modification of 

 habitat Y?" (Thomas and West 1989). Findley (1993) concluded 

 that the best that can be done by a community ecologist studying 

 bats is to assess the relative abundance of different species and 

 to compare regions and habitats with respect to the numbers of 

 bats obtained for given amounts of effort applied. 



Summer roost counts, visual counts of foraging bats, ultrasonic 

 detectors, vampire bites, and mist-netting and trapping were 

 methods listed by Thomas and LaVal (1988) to estimate bat 

 abundance in habitats or other geographic areas. The use of 

 ultrasonic detectors and mist-netting were selected as methods 

 for this study as no summer roost sites were known in the study 

 area prior to the study, there are no vampire bats, and visual 

 counts are limited to a short time after dusk, prior to the time 

 many species in Montana emerge from day roosts. 



Species occurrence 



One of the objectives of this study was to document the 

 occurrence of bat species on the Deerlodge National Forest. 

 There are 14 species of bats in Montana (Thompson 1982). Several 

 of these are not expected to be on or near the Forest due to 

 limited distribution in the state, such as the Spotted bat 

 (Euderma maculatum) and the Pallid bat (Antrozous pallldus) , both 



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