26 
PROCEEDINGS OF THE CALIFORNIA ACADEMY OF SCIENCES 
Series 4, Volume 65, Supplement I 
Examination of fecal pellets and culled insect wings from beneath roosts of Rafinesque’s big- 
eared bats in Kentucky suggests that these bats are moth specialists, preying on moths with 
wingspans from 31 to 57 mill im eters: the diet is greater than 80% moths followed by beetles and 
other groups as the next most utilized dietary components (Hurst and Lacki, 1997; Lacki and 
Ladeur, 2001). This generally holds true across study areas (Lacki and Dodd, 2011). Moths that 
were consumed in the Kentucky studies were predominantly sphinx moths and noctuids of the 
genus Catocala, many members of which feed on oaks and hickories as larvae (Hurst and Lacki, 
1997, 1999). Further analysis of fecal pellets sampled in Kentucky using DNA-based prey identi¬ 
fication techniques showed that prey size may be over-estimated using earlier methods, but veri¬ 
fied that lepidopterans (particularly macrolepidopterans) were the primary prey (Dodd et ah, 2015). 
In addition to a diet rich in moths, dietary analysis of fecal pellets from a North Carolina 
colony revealed that although 67% of the sample volume were lepidopterans, 31% were tabanid 
dipterans (for example, horse flies), suggesting that these bats could contribute to control of taban- 
ids as pests and vectors of disease (Ellis, 1993). Analysis of fecal pellets from the more southern 
parts of their distribution in Florida and Louisiana also confirmed that Rafinesque’s big-eared bats 
primarily eat lepidopterans, and that they will feed year-round (Whitaker et ah, 2007; Gregory et 
ah, 2014). In a review of several feeding studies, Lacki and Dodd (2011) reported that moths most 
frequently taken in order of presence in the diet belong to the families Noctuidae, Geometridae, 
Sphingidae, and Arctiidae. 
Roosting Habits. — Rafinesque’s big-eared bats have been reported to roost in hollow trees, 
under loose tree bark, in caves, and in a variety of human-made structures including culverts, 
bridges, abandoned buildings, wells, cisterns, bams, empty oil storage tanks, abandoned house 
trailers, and min es (Moore, 1949; Pearson, 1962; Mumford and Whitaker, 1982; Schmidly, 1991; 
Hurst and Lacki, 1999; Lance et ah, 2001; McDonnell, 2001; Clark, 2003; Felts and Webster, 2003; 
Gooding and Langford, 2004; Trousdale and Beckett 2004, 2005; McCartney, 2007; Martin et ah, 
2011; Sasse et ah, 2011; Trousdale, 2011; Clement and Castleberry 2013b,c). Rafinesque’s big- 
eared bats are often found roosting at the same sites with tricolored bats (Perimyotis subflavus ) and 
southeastern myotis (Myotis austroriparius ), and to a lesser degree will also share roosts with other 
species (for examples, Jones and Suttkus, 1975; Jones, 1977; Mumford and Whitaker, 1982; Clark, 
1990; Hurst and Lacki, 1999; Ferrara and Leberg, 2005b). 
Winter Roosts in Caves and Human-Made Structures: Winter roosts of Rafinesque’s big- 
eared bats include caves, cavities in rock piles (talus caves), mines, cisterns, buildings, and hollow 
trees. Rafinesque’s big-eared bats consistently occupy hibemacula throughout the winter in the 
northern parts of the range, but may move between colonies in late winter and early spring 
(Hoffmeister and Goodpaster, 1962). In large areas of their range, these bats may not undergo pro¬ 
longed, deep hibernation during winter. 
In geologically suitable areas, Rafinesque’s big-eared bats regularly winter in caves and min es. 
According to Sealander and Heidt (1990), in the northern part of its range, this species hibernates 
in the cool twilight zone of caves, often within 10-35 meters of entrances. One sandstone cave 
monitored in southeastern Kentucky from 1993-1998 was used by this species throughout the year 
and housed from 14 to 49 bats in winter (Hurst and Lacki, 1999). This species hibernates in silica 
mines and caves during winter in southern Illinois (Hoffmeister, 1989). Solitary hibemators were 
reported in a cave and a talus cave or rock shelter in Arkansas (Saugey et ah, 1993). Hibernating 
individuals at Mammoth Cave National Park in Kentucky aroused from their relatively shallow 
(compared to other North American hibernating bats) winter torpor (skin temperature 13.9 degrees 
Celsius [°C] ± 0.6 SE) near sunset every 2.4 days, and switched winter roosts in caves (and aban¬ 
doned buildings) every 4.1 days (549 to 5,964 meters between consecutive roosts), presumably for¬ 
aging after some arousals (Johnson et ah, 2012b). 
