New York Natural Heritage Program
Indiana Bat
Myotis sodalis Miller and Allen, 1928
Mammals

Threats [-]
Indiana bats had suffered significant past declines and were listed as endangered in 1967 (USFWS 2014). Past disturbances to winter hibernacula were thought to have resulted in decline since they hibernate in limited locations and are suceptible to disturbance. Currently, the largest threat to Indiana bats in New York is white-nose syndrome (WNS) which was first discovered among bats in a cave in Schoharie County, New York in 2006. White-nose syndrome is caused by a fungus Pseudogymnoascus destructans (previously Geomyces destructans) that is often visible on the bats' muzzle and wings (Blehert et al. 2009). The fungus may invade hair follicles and cause lesions under the skin (Blehert et al. 2009). Bats wake from hibernation to groom and consequently burn fat reserves that are needed to survive the winter and they become emaciated (Blehert et al. 2009). Extensive damage to their wing membranes and dehydration may also be contributing factors to mortality (U.S. Fish and Wildlife Service 2013).
Tree cutting can impact this species when felled trees contain colonies or roosting individuals. There are very few colonies left in New York so loss of summer roosts containing bats is even more devestating to dwindling populations. Habitat loss from development is also a threat which can limit suitable habitat.
Bats may be particularly sensitive to environmental toxins including those found in herbicides and pesticides. Although no studies have targeted Indiana bats in New York directly, elevated levels of persistent organic pollutants including especially PCBs, DDT, Chlordanes, and PBDEs have been found in a similar species, the little brown bat, in the Hudson River Valley in New York (Kannan et al. 2010). The levels found in the bats were only 1 to 3 times less than lethal concentrations reported from previous studies (Kannan et al. 2010). Lesser toxin levels may be expected in Indiana bats since little brown bats typically consume a greater percentage of prey with an aquatic life stage. Bats are highly susceptible to DDT residue and this chemical was widely used as a pesticide to control bat infestations in houses in the 1940s (USGS 2013). It was widely used as an agricultural pesticide in the 1950s and 60s until its agricultural use was banned in 1972. Since DDT is highly persistent (soil half-life is 2-15 years, aquatic half-life is about 150 years) (NPIC 1999), it can pose a threat to bats when there is exposure to trace residues in the environment (USGS 2013). Extensive applications of insecticides and some bio control methods, such as Btk, could also pose an indirect risk to Indiana bats by reducing availability of prey.
If proper precautions are not used, cavers and researchers entering hibernacula may cause disturbance that rouses bat colonies or transport the fungus that causes WNS on their clothing (NatureServe 2013). Other potential threats may include climate change, commercial cave development, flooding and hibernacula collapse; habitat loss and fragmentation from development, hydraulic fracturing, and construction of new wind facilities; and direct mortality from wind facilities (U.S. Fish and Wildlife Service 2013).

Conservation Strategies and Management Practices [-]
Continue to monitor populations at hibernacula every other year as recommended by the United States Fish and Wildlife Service.

Research Needs [-]
Additional research is needed to locate new maternity and bachelor colonies and to determine habitat use surrounding these areas.