INTRODUCTION 



Numerous sites along the Norris Junction-Mammoth Junction road were evaluated for bat use during the 

 s ummer season in 1997 and 1998. All known case sites were checked and special attention was given to water 

 bodies near the road since these areas are known to draw bats from the surrounding region for feeding and 

 interaction. A total of 33 sites were studied ranging from a known maternity pit cave site to a cold alpine pond. 

 The primarj objective was to identify and document bat presence and activity along the corridor affected by 

 reconstruction of the Grand Loop Road between Norris and Mammoth. Information gathered from field activities 

 would be used to make sound management decisions on protecting the available resources and reducing the 

 impact of construction activities on future projects of this type. 



Figures 1 through 6 identify the locations of each site studied on a portion of the USGS topographic- 

 quadrangle and Table 2 is a lisimg of the latitude and longitude readings from either the topo map or from GPS 

 instrument readings taken in the field. Although care was taken to get as much information as possible, a wide 

 variety of habitat settings were tested to provide the clearest picture of overall bat activity in the study area. 



METHODS 



Bat occurrence and identity were determined in open areas and in probable roost sites located within the 

 road corridor using traditional and low impact methods. Mist netting and subsequent in-hand identification of 

 captured bats was attempted at one or two sites each night, although weather conditions on some nights 

 prevented deployment of the nets. Known caves and other likely roost sites were visited and examined for 

 evidence of bat use and suitability. For three of the caves in the Mammoth area, vertical rope techniques were 

 employed to safely enter the pit entrances of natural caves. For confined spaces in areas where poison gas might 

 be encountered, a gas monitor was used to detect oxygen deficiency and the presence of methane or explosive 

 gases. 



For a greater number of sites an ANABAT ultrasonic bat detector (Titley Electronics; Ballina, Australia) 

 was used in conjunction with a Titley Delay Switch and cassette recorder to monitor and record bat activity 

 during the nighttime hours. These electronic sensors can successfully record ultrasonic calls over a wide band 

 of frequencies from 20 to 180 kHz without producing any sound of their own and are undetectable by bats. 

 Many bat species can be identified from their recorded calls on the basis of known characteristics and call 

 structures revealed from analysis of the audio recordings. Analysis of the recordings took place at the Montana 

 Natural Heritage office in Helena using an IBM compatible personal computer with ANABAT II zero crossings 

 analysis interface module and software 



RESULTS 



Bats of six different species were identified from calls recorded by the Titley Electronics' ANABAT set- 

 up. Table 3 lists those species and their common names. Numerous undifferentiated Myotis were detected but 

 could not be identified to species with certainty because of poor call quality or insufficient duration. Because 

 of the similarity of all Myotis spp. calls, they often cannot be distinguished from each other by analysis of the 

 calls alone, I wo ol the identified bat species are of special concern, Townsend's big-eared bat, Corynorhinus 

 towruendii, and the fringed myotis, Myotis thysanodes. 



Table 1 lists the results of from each site and provides a summary of numbers of calls during each hour 

 time period from dusk until dawn. 



Devils Kitchen : This is a known maternity site for bats in the Mammoth area Historically, it is well known 

 for Townsend's big-eared bats, hut it also provides roosting for other species in an area where a variety of bat 

 species have been captured and recorded. 



On September 27, 1997, a descent was made into the cave to document bat activit) and environmental 

 conditions. A partial SUTVe) was made to record the dimensions and identity rOOSting areas important to bats 

 observed at that time. Approximately 86 feel of passage were surveyed with about 40 more feet left to be 



