As mentioned in previous posts, white nose syndrome is responsible for the decimation of hibernating North American bats. The cause of death is starvation attributed to increased arousal when the bats should be hibernating.
Dr. Craig K.R. Willis and colleagues have published new findings supporting the plausibility of ” the dehydration hypothesis”, that infections on the wing membranes of bats leads to dehydration thereby increasing the frequency of arousals. They found that the rate of evaporative water loss (EWL) was higher for a species that is most susceptible to WNS, little brown bats (Myotis lucifugus), compared to a species for which WNS has a much lower mortality rate, Natterer’s bats (Myotis nattereri). Under both dry air (panel A) and humid air (panel B) conditions, the Natterer’s bats had lower levels of EWL compared to the little brown bats. The findings are depicted in figure 3 from the paper:
Some of the data are predicted from the literature. But the author’s findings suggest that another trigger for early arousal may be to help maintain water balance. Clearly more research into the nature of WNS should be conducted to help eradicate this deadly fungus.
CKR Willis, AK Menzies, JG Boyles, MS Wojciechowski. Evaporative water loss is a plausible explanation for mortality of bats from White-nose syndrome. Integrative and Comparative Biology 51(3): 364-373, 2011.