During ongoing population censuses carried out at hibernacula in different countries across Europe and during additional hibernacula surveys carried out for the purpose of this study, information on bats with visible white fungal growth on snouts and/or ears was recorded.
Anecdotally, bats at hibernacula affected by WNS are sometimes seen flying over and drinking from water surfaces or eating snow (A Hicks, personal communication), highlighting the plausibility of the dehydration hypothesis.
Swarming begins in August, when bats of both sexes congregate at sites that will later serve as hibernacula, apparently to assess the site's suitability for hibernation, and later to mate and commence daytime torpor [23], [25] [26].
Losses at affected hibernacula have exceeded 75% [ 1], and some winter colonies that were stable or increasing in number for decades have all but disappeared [ 2].
To test our hypothesis, we studied the invasion dynamics of the WNS fungus by sampling bats of 5 species at 2 hibernacula in central Illinois, USA.
In North-America, Lindner et al. [48] successfully amplified ITS sequences identical to G. destructans DNA from soil samples collected during the winter 2008 2009 at three bat hibernacula and stressed the importance of considering the environment as a reservoir for G. destructans and in the dynamics of WNS transmission.
In the summer of 2014 and winter of 2015, we collected 385 samples from hibernacula surfaces at 12 sites in 3 provinces and 1 municipality and 215 samples from 9 species of bats at 10 sites (summer: Rhinolophus ferrumequinum, Rhinolophus pusillus, Myotis adversus, Myotis macrodactylus, Myotis pilosus, Myotis chinensis, Murina usseriensis; winter: R. ferrumequinum, Murina leucogaster, Myotis petax).
During regular monitoring through the most recent winter of 2009/2010 (January/February), WNS-suspect bats were found at 33 sites out of over 800 hibernacula in the Czech Republic (CZ) and Slovakia (SK), combined.
Thus, we have identified many antifungal drugs that work well in the laboratory against Gd at temperature ranges likely to be encountered in bat hibernacula.
Unfortunately, bats, in particular myotid bats, are most accessible in their hibernacula, their maternity roosts (when most are pregnant or lactating), or at swarming sites (of which few are known and include mainly male bats).
Another new study related to survival of bats with WNS suggested a possible connection between environmental conditions outside of bat hibernacula and WNS mortality, with a higher likelihood of mortality occurring at hibernation sites situated in cold, seasonally variable, high-elevation regions [ 14].
