Together, these data provide important insights on WNS survivors and have several implications for the possibility of long-term survival of little brown myotis in eastern North America. Bats with greater body condition, indicative of greater fat reserves, were more likely to survive our experiment. Because bats rely on the metabolism of fat to arouse from torpor and sustain brief periods of euthermy during hibernation, fat reserves limit the number of times a bat can arouse. Thus, bats with greater body condition at the onset of hibernation can sustain more arousals during the course of a winter, making them better suited to surviving the increased frequency of arousals associated with WNS. In a study of free-ranging bats affected by WNS, however, Reeder and colleagues found no relationship between date of death and body condition. This discrepancy likely results from the confounding effects of other pertinent variables influencing the disease. As our results show, WNS mortality is driven by the interaction of variables pertaining to not only the host, but also the pathogen and the environment. Understanding how our results, obtained under carefully controlled conditions, compare to survival and mortality of wild populations requires the incorporation of all these variables, and provides a foundation for hypotheses related to the persistence of little brown myotis in the WNS-affected region of North America. Females also exhibited greater survival probability in our study. Female little brown myotis are frequently documented with greater mass or body condition OTX015 compared to males in the late fall or early winter, a difference also present in our captive sample. Although females in our study had greater body condition than males at the onset of hibernation, we did not find a large correlation between sex and body condition in our survival analysis, demonstrating that while large body condition contributes to survival in females, there are other sex-based differences contributing to variation in mortality. Jonasson and Willis found that hibernating little brown myotis females have less pronounced declines in body mass over winter compared to males, but were unable to attribute this to differences in torpor patterns during hibernation between the two sexes. We were also unable to detect differences in mean torpor bout duration between males and females in our overall analysis, although statistical power was low. A limited comparison of torpor bouts between males and females in control groups did reveal differences in torpor behaviors, however, potentially explaining why females had higher survival rates than males. This was true of inoculated as well as control bats; 83% of the mortality observed among control bats hibernated at 10uC consisted of males with body condition below that of any female in the group. Differences in winter body condition and torpor behaviors between male and female little brown myotis are believed to be related to the reproductive biology of the species. Because copulation occurs throughout fall and winter, and ovulation occurs in spring after emergence from hibernation, several have argued that males benefit.