of the Silver-haired bats in their stuc3y roosted in old-growth 

 Douglas fir. They speculate that Hoary bats prefer these older trees 

 because they roost in foliage, and older trees provide a combination 

 of shelter, open space to gain flight vrtien leaving the roost, and 

 ijimediate accessibility upon return. Silver-haired bats appear to 

 prefer older Douglas fir trees because the bark tends to pull away 

 from the bole providing crevices for shelter. Older trees are also 

 may provide roosting crevices or cavities created by wind and 

 lightning damage, shed limb holes, excavations by cavity nesting 

 birds, cracks in the wood, and so on (Perkins and Cross 1988). Old- 

 growth ponderosa pine provided some roosting sites, but was not 

 selected as often by bats as old-growth Douglas fir because bark 

 ridges are not as deep and bark exfoliation is not as common in 

 ponderosa pine ( Perkins and Cross 1988 ) . 



Bats may roost in numerous sites within a forest exclusive of old- 

 growth timber. Old buildings, including recreational cabins and 

 buildings associated with abandoned mines, provide favored sites for 

 some species, inclioding the Little bixiwn bat and the Big bmwn bat 

 (Fenton 1992), but these are often unavailable in much of the 

 forested west. Caves and adits may provide roosting sites for many 

 species of bats ( Fenton 1992 ) . Many of the Myotis species including 

 the Fringed bat, the California myotis, and the Small-footed bat 

 (Myotls ciltolahnxa) , have been found roosting in fissures and under 

 rock slabs (Thomas and West 1986). 



29 



