36 
PROCEEDINGS OF THE CALIFORNIA ACADEMY OF SCIENCES 
Series 4, Volume 65, Supplement I 
young, but additional management zones should be extended to at least 2.5 kilometers around 
known roosts to protect foraging habitat of adults. 
Disturbance by investigators during periodic monitoring of use of bridges by Rafmesque’s big- 
eared bats does not seem to affect subsequent use of these sites in Louisiana, situations wherein 
colonies are small and bats are easily seen (Ferrara and Leberg, 2005b). However, because of fre¬ 
quent roost switching and temporary absences of bats, the research in Louisiana showed that at 
least three surveys during summer were necessary to have a less than 10% chance of misidentify- 
ing a roost bridge as not being used. Other investigators determined that bridges should be visited 
three to five t im es per year to assure detection of use (Bennett et al., 2008). Rafinesque’s big-eared 
bats will accept certain gate designs at mouths of abandoned mines, and gated mines house some 
of the largest known hibernating colonies of this species (Burghardt, 2000). 
Rafmesque’s big-eared bats will use manmade structures specifically built to mimic their 
roosts (Bayless, 2006). Cinder-block towers (4.3 meters tall) were used at Trinity River National 
Wildlife Refuge in Texas, with bat use of specific towers apparently varying with seasonal thermal 
preferences (Bayless, 2006). Artificial roosts constructed by stacking concrete culverts to mimic 
hollow trees have been successfully colonized by Rafmesque’s big-eared bats at St. Catherine 
Creek National Wildlife Refuge in Mississippi, where one roost was used as a maternity colony by 
about 30 bats in 2006 (McCartney, 2007; Martin et al., 2011). On Noxubee National Wildlife 
Refuge in Mississippi, artificial roosts made of up-ended steel culverts were observed to be used 
by these bats in spring and autumn (Stevenson, 2008; Martin et al., 2011). Also at Noxubee Nation¬ 
al Wildlife Refuge, the U.S. Fish and Wildlife Service has added openings to trees with cavities that 
had no previous access points for bats: Rafinesque’s big-eared bats have been observed subse¬ 
quently using these trees as roosts (Richardson, 2007). Given the large degree of roost switching 
used by these bats, protection and management of areas with tracts large enough to support multi¬ 
ple roosts is important. 
Because the diet of this species has a high composition of lepidopterans, concern exists for 
possible impacts on the food supply due to forest insecticide treatments against pest moths (Lacki 
and Bayless, 2013). 
Notes and Comments. — Several important research papers on C. rafinesquii appear in the 
volume edited by Loeb et al. (2011a), including literature reviews pertinent to their conservation 
and management (for example, Loeb et al., 2011b; Miller et al. 2011). Bat Conservation Interna¬ 
tional and the Southeastern Bat Diversity Network have developed a conservation and management 
plan for Rafmesque’s big-eared bat and the southeastern myotis (Lacki and Bayless, 2013) that 
reviews additional detailed biological information, major threats and conservation needs, and pro¬ 
vides well-considered specific suggestions for future research and conservation strategies. The 
major past, present, and future threats identified include those noted above, and are grouped as: loss 
and degradation of bottomland hardwood forest; altered hydrology; climate change; loss and degra¬ 
dation of mature upland forest; loss of natural roosting habitat; loss of anthropogenic roosting habi¬ 
tat; disturbance at roosting sites; disease; white-nose syndrome; wind energy development; air 
strikes; loss of genetic diversity; and insufficient conservation planning. Areas of needed actions 
discussed in the document (Lacki and Bayless, 2013) include further identification of occupied 
habitat and roost sites, protection and creation of roosts, development and implementation of pop¬ 
ulation inventory and monitoring methods, population genetics research, management of foraging 
habitat, monitoring for new and emerging threats, education and outreach, development of conser¬ 
vation incentives, and recommendations for research. 
