Several transect locations were located in large blocks of 

 homogeneous forest types, considerably removed from roads or large 

 creeks. The transect along the Ross Creek Cedars trail is 

 entirely contained in old growth western red cedar forest. The 

 transect along the clearcut by road 427 is similarly contained 

 within a uniform clearcut with seed trees evenly interspersed 

 throughout . Other transects were relatively contained within 

 constant habitat types, such as Bull Lake (lake edge trail in 

 uneven-aged pine and cedar forest) and Bear Creek (mature to old- 

 growth cedar forest along creek) . As a group, the transects on 

 the Superior Ranger District were within a drier climate, marked 

 by a higher abiindance of Douglas-fir and ponderosa pine. 



The low relative bat activity found at the clearcut area by road 

 427 is expected, and likely not a casualty of sampling variability 

 or poor luck. This area does not provide roosting habitat for 

 bats. Likewise, bats that feed over water or in the forest canopy 

 would not be expected to utilize clearcut areas. The low relative 

 bat activity found at Ross Creek Cedars may have been influenced 

 by poor weather, although it is more likely that the transects 

 took place after most bats had left their roosts and moved to more 

 suitable foraging habitat. On 15 July, nvomerous bats were 

 observed feeding high over Ross Creek prior to the start of the 

 transect. The fairly low levels of bat activity found at Slowey 

 Gulch, Dry Fork, and Flat Creek may be indicative of true low 

 relative bat abundance associated with the drier forest found 

 there, or possibly be caused by sampling late in the year at each 

 of these sites. 



Reproductive success 



The obseirved low percentage of reproductively active females (24%) 

 and the very low proportion of juvenile bats (Center pers . comm. ) 

 is likely due to the cold, wet spring and summer experienced 

 throughout western Montana in 1993 . Female bats must maintain 

 homeothermy during pregnancy and lactation, while males can go 

 torpid if climactic conditions are unfavorable for foraging. The 

 high metabolic costs of pregnancy, combined with weather 

 conditions that negatively influence insect abundance, can cause a 

 reduced fecundity in bats. Pregnant females that cannot meet 

 their energy needs must enter into torpor, causing delayed 

 parturition, failed reproduction, or death (Racey 1982). For 

 colonial breeders {Myotis spp . , Plecotus townsendii, and Eptesicus 

 fuscus) , high-quality roosting habitat is especially important in 

 unusually wet and cold years. Maternity roost sites must be of 

 sufficient number and quality to provide bats with the 

 thermoregulatory benefits of colonialism, and buffer against poor 

 weather . 



15 



