During 1991 and 1992, eight species of bats, representing four genera, were documented by capture during this phase of the study. These were the Big brown bat, (Eptesicus fuscus), the Little brown bat (Myotis lucifugus), the Yuma bat (Myotis yumanensis), the Northern long-eared myotis (Myotis evotis), the small-footed Myotis (Myotis ciliolabrum), the Fringed Myotis (Myotis thysanodes), the Hoary bat (Lasiurus cinereus), and the Silver-haired bat (Lasionycteris noctivagans). The Fringed myotis is on the Montana Natural Heritage Program's list of species of special concern (Genter 1993). Another species of special concern that was possibly observed on the Deerlodge National Forest, but was not positively identified, was the Townsend's big-eared bat (Plecotus townsendii). Several were possibly observed in the vicinity of the Crater on Pike's Peak Creek late in the summer of 1992. Relative bat densities varied between habitats. Those with rock-outcrops, beaver ponds, mature hardwoods, mature Douglas fir, or riparian areas nearby had the greatest bat activity during both years of the study. Findley (1993) stated that an increase in species richness accompanies increased availability of roosts. "Forested regions lacking cliffs, caverns, and caves support fewer species, and those that do occur are known to use trees as daytime roosts in summer. Mountains, broken topography with opportunities for roosting in crevices, cliff faces, caverns, and caves support richer communities" (Findley, 1993). Management activities that encourage undisturbed stands of old-growth forest, especially old stands of Douglas fir and mature hardwoods, the maintenance of healthy riparian areas, including snags and old individual aspens and cottonwoods, and the preservation of caves and access to abandoned mine adits will provide roosting and foraging habitat for a diversity and abundance of bats. Management activities that encourage large monocultures of relatively young trees, and even-aged management of forest stands will be detrimental to the diversity and abundance of bats using the forest.