30 
PROCEEDINGS OF THE CALIFORNIA ACADEMY OF SCIENCES 
Series 4, Volume 65, Supplement I 
had larger dimensions in cavity volumes. In general, tree occupancy rates decreased with degree of 
past habitat disturbance, but the diversity of tree species and forest and wetland types increased, 
and the influence of cavity attributes of occupied trees and the probability of detecting a roost var¬ 
ied among areas (Loeb, 2017). 
Texas : Little roost switching was observed in seven radio-tracked Rafinesque’s big-eared bats 
on public lands in the pineywoods ecoregion of eastern Texas, thought possibly due to a low avail¬ 
ability of suitable roost trees (Stuemke et al., 2014). In eastern Texas, transect searches and radio 
tracking of the seven bats showed that compared to unused trees, roost trees (primarily Nyssa spp.) 
had larger diameters and cavities, greater numbers of entrances, and were larger; roost trees also 
were in trees with entrances higher above ground, and were located in stands with higher numbers 
of large trees (Stuemke et al., 2014). 
Warm Season Roosts in Human-made Structures: Rafinesque’s big-eared bats also roost in 
buildings during the warmer months. As with winter roosts, buildings, bridges, cisterns, and other 
human-made structures used as roosts can be occupied for multiple years (for example, Hoffmeis- 
ter and Goodpaster, 1962; Jones and Suttkus, 1975; Clark, 2003; Loeb and Zamoch, 2011). Multi¬ 
year fidelity of Rafinesque’s big-eared bat to roost sites in abandoned buildings was documented 
in eastern North Carolina (Clark, 1990). Differences in temperature, light levels, and disturbance 
rates between occupied and unoccupied buildings were not found in eastern North Carolina (Clark, 
1990). Sealander and Heidt (1990) reported that in Arkansas this bat roosts in dimly lit bam lofts, 
attics, and old buildings in mral areas, but it is seldom found in caves. Saugey et al. (1989) 
observed a colony of more than 100 individuals in an abandoned Arkansas school in autumn, a 
“nuisance” colony of about 65 was reported in the belfry of a church (McAllister et al., 2005), and 
up to 175 bats (including a maternity colony) intermittently used an Arkansas barn beginning short¬ 
ly after its constmction (Saugey et al., 1993). In southern Illinois, small groups of 30 or fewer have 
been reported in summer from a house attic and in an old cabin (Hoffmeister, 1989), and small 
numbers were reported from an attic in western Tennessee (Graves and Harvey, 1974). A materni¬ 
ty colony of several hundred bats roosted in a building in Mammoth Cave National Park in Ken¬ 
tucky (Harvey et al., 1991). In eastern North Carolina, these bats also roosted in darker parts of 
abandoned buildings but moved to cooler roosts with more light if ambient temperatures in dark 
sites climbed over about 36°C (Clark, 1990). Local switching of roost sites among a few nearby 
buildings was reported in Louisiana, where they were encountered in clusters in summer nursery 
colonies, typically in partially lighted front areas of roosts (Jones and Suttkus, 1975). Abandoned 
buildings were used as roosts in Mississippi (including roosts in buildings on or near wildlife 
refuges), with one roost used by a maternity colony of 62 bats, but no Rafinesque’s big-eared bats 
were found in searches of caves and cisterns (McCartney, 2007). 
This species often moves between natural and human-made roosts. Clark (2003) reported that 
individuals of this species that roost in buildings in a number of southeastern states will shift from 
buildings to roosts in hollow trees in wetlands. Bats radio tracked in eastern Texas made move¬ 
ments among trees, buildings, or other human-built structures (Stuemke et al., 2014). In south-cen¬ 
tral North Carolina, Rafmesque’s big-eared bats used abandoned structures and hollow trees as 
roosts about equally, switching roosts every one to two days (Roby et al., 2011). Small numbers 
also roosted in bridges in southeastern North Carolina (Felts and Webster, 2003). In De Soto 
National Forest in southern Mississippi, Rafinesque’s big-eared bats roosted in human-built struc¬ 
tures (including bridges, abandoned houses, and an abandoned oil storage tank) as well as in hol¬ 
low trees, switching roosts every 2.1 days; half of the 14 maternity roosts discovered were in 
anthropogenic structures, where fidelity to roosts was higher in the absence of tree roosts (Trous¬ 
dale et al., 2008). The 25 tracked bats moved between successive roosts that were an average of 
