RITUAL REQUIREMENTS 



The bats swarm near caves from August to 

 November in Missouri and from mid-August to 

 the end of October in Indiana and Kentucky 

 (Cope and Humphrey 1977). Swarming is des- 

 cribed as a phenomenon in which large numbers 

 of bats fly in and out of a cave entrance from 

 dusk to dawn, while relatively few roost in the 

 cave during the day (Humphrey and Cope 1976). 

 The significance of this activity is not known; it 

 has been suggested that it relates to mate selec- 

 tion and copulation, adjustment to and familiari- 

 zation with seasonal ranges, and/or rest stops 

 during migration (IBRT 1975, M. D. Tuttle per- 

 sonal communication). 



OTHER CRITICAL ENVIRONMENTAL 

 REQUIREMENTS 



It is possible that in some instances, the gray 

 bat (My Otis grisescens), another Federally hsted 

 endangered species, may compete for roosting 

 space in winter caves (Hall 1962) and could pos- 

 sibly displace the Indiana bat from them. 



POPULATION NUMBERS AND TRENDS 



The recent discovery of two new winter caves 

 has brought estimates of total population to 

 509,000 (Richter et al. 1978). The bat once 

 numbered 1 million, but major catastrophies, 

 primarily flooding, killed many in wintering caves 

 (Hall 1962, IBRT 1975). 



Humphrey (1978) recorded a 28% decline in 

 total numbers from 1960 to 1975 (Table 1). 



Table 1. Population estimates and trends for the 

 Indiana bat, by state 



The decline in Kentucky was due to flooding, 

 disturbance, and man-caused alteration of cave 

 climate. Humphrey (1976) believs the Indiana bat 

 is headed for extirpation in Kentucky. Missouri 

 reductions are a result of winter weather variation. 

 Incidents of vandalism and the collapse of a mine 

 contributed to the decline in Illinois (Mohr 1962, 

 Humphrey 1978). The overall trend at present 

 will lead to the species' extinction in 50 years, 

 but most losses of winter habitat are reversible 

 and this eventuality can be avoided (Humphrey 

 1978). 



REPRODUCTION 



Copulation occurs in the fall with the females 

 storing the sperm over the winter (Barbour and 

 Davis 1969). The females form nursery colonies 

 under the bark of trees in late spring (usually 

 May) and give birth to one young in late June or 

 early July (Humphrey et al. 1977). Only females 

 and young occupy the nursery roost (Humphrey 

 et al. 1977). The longevity record for males is 

 13.5 years; for females, 14.8 years. The survival 

 rate for females is high for the first 10 years, 

 and for males, for the first 6 years only (Hum- 

 phrey and Cope 1977). 



MANAGEMENT AND CONSERVATION 



The primary conservation effort to date has 

 been to control human access to caves by the 

 use of gates. The National Park Service, the U.S. 

 Forest Service, and some State agencies have 

 installed gates on several caves. The Recovery 

 Team suggests the gating of several more caves 

 and mines, which will give protection to 99% of 

 the bats (IBRT 1975). In one instance (Colossal 

 Cave, Kentucky), a gate modified cave micro- 

 climate and made it unsuitable for bats (Hum- 

 phrey 1978). Gates or fences have also increased 

 the bats' susceptibility to predation at the en- 

 trances (Tuttle 1977). Other conservation efforts 

 include a moratorium on issuance of bat bands by 

 the U.S. Fish and Wildlife Service and restrictions 

 on use of pesticides such as DDT. The National 

 Speleological Society has appointed a Bat Con- 

 servation Task Force and has taken some specific 

 measures to protect bats. 



The original Recovery Team (since disbanded) 

 outlined a Recovery Plan (IBRT 1975) listing 

 three objectives critical to preservation of the 

 species: (1) protecting winter habitat by securing 

 caves and mines and restricting entry; (2) initi- 

 ating a public information and education pro- 



