O’SHEA, CRYAN & BOGAN: UNITED STATES BAT SPECIES OF CONCERN 
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considered uncommon or rare in the northe rnm ost states within its range (Barbour and Davis, 1974; 
Hoffmeister, 1989; Sealander and Heidt, 1990). According to Mumford and Whitaker (1982), win¬ 
tering populations in these areas decreased substantially since 1949. In southern Illinois, a search 
of 52 suitable caves and mines during winter in 1982-1991 revealed just one inhabited by south¬ 
eastern myotis (Gardner et al., 1992). This site showed a range of counts among winter visits of 
from two to 220 hibernating individuals, with the bats seeming easy to arouse. Two sites with larg¬ 
er numbers (90-120 and 120) of hibernating bats in the past were no longer used or suitable due to 
vandalism or modification (Gardner et al., 1992). 
The first documented locality for this species in Arkansas was a mine drift in the Ouachita 
Mountains that was subsequently inundated by an impoundment (Davis et al., 1955); a second 
locality discovered in the Ouachita Mountains was an abandoned mine that housed 150 hibernat¬ 
ing bats in 1984, but the winter population declined to just a few individuals by 1986 as a likely 
result of disturbance (Saugey et al., 1988). The only known maternity colony in Alabama, report¬ 
ed to consist of about 8,000 bats in summer 1990, was reported as being “extremely vulnerable to 
destruction” because of disturbance and vandalism (Best et al., 1992:64). Another summer colony 
at a different cave was previously described as the largest in Alabama, but it had been extirpated 
by the mid-1980s. In Louisiana and eastern Texas, the southeastern myotis is considered wide¬ 
spread but rare (Lowery, 1974; Lance and Garrett, 1997; Mirowsky et al., 2004). 
In Florida, where the species is considered most abundant (Amelon et al., 2006), populations 
occur in two regions: the panhandle and the north-central peninsula (Gore and Ho vis, 1994). 
Humphrey and Gore (1992:335) caution that for Florida “uncertain accuracy of population esti¬ 
mates and ignorance of seasonal movements among caves precludes evaluation of trends from the 
scanty data available.” Given this caveat, most of the existing information is suggestive of declines. 
Rice (1957) felt that in northern peninsular Florida he had located most of the maternity colonies 
in existence during the early 1950’s (which may not have been the case [Gore and Hovis, 1994]), 
with most in just 6 caves. At that time Rice (1957) crudely calculated a total population of about 
334,000 southeastern myotis at these caves. During the early 1990’s, one cave that previously 
housed a colony of 2,500 (Rice, 1957) was gone, a second of 90,000 remained at about the same 
numbers, and a third of 30,000 was on a site scheduled for development of a housing project 
(Humphrey and Gore 1992). One report suggested that a summer population of 112,000 bats in the 
Florida panhandle had dropped to 31,000 by 1970 (Lee and Tuttle, 1970). Estimates of populations 
in four caves in the panhandle during 1987 to 1989 were: greater than 2,000, about 3,000, less than 
50,000, and greater than 50,000. Three caves in the Florida panhandle that had previously sup¬ 
ported populations, including a colony of 11,000 at one in the 1950s, were completely devoid of 
bats by the early 1990’s (Humphrey and Gore, 1992), and another cave in the Florida panhandle 
with a maternity colony documented at 15,000 in 1970 had fewer than 200 in 1981 (Wenner, 1984). 
Apparent declines at Florida caves prompted an intensive statewide survey for maternity 
colonies in 1991-92 (Gore and Hovis, 1994, 1998). Only nine caves in Florida harbored materni¬ 
ty populations, with 10 historic sites known to be used by southeastern bats at past times no longer 
occupied by bats. Caves with historical maximum population estimates (adults prior to parturition 
only) noted at various t im es from 1936-1982 totaled about 380,000 bats; in 1991-92 maxima of 
about 243,000 were estimated at these same sites and a total for all sites occupied in 1991-92 in 
both peninsular Florida and the panhandle combined was about 320,000 bats (Gore and Hovis, 
1994, 1998). These numbers are suggestive of lower populations but are not directly comparable 
to earlier estimates because it is unknown how many of the earlier sites were continuously or simul¬ 
taneously occupied, how many undiscovered populations had existed in the recent past, how much 
movement occurs among sites, and how methods of estimation may have differed. Most of the 
maternity colonies visited in 1991 or 1992 showed evidence of successful production of young, 
