Shifts in population density centers of a hibernating mammal driven by conflicting effects of climate change and disease.

Populations wax and wane over time in response to an organism's interactions with abiotic and biotic forces. Numerous studies demonstrate that fluctuations in local populations can lead to shifts in relative population densities across the geographic range of a species over time. Fewer studies attempt to disentangle the causes of such shifts.

White-nose syndrome fungus: a generalist pathogen of hibernating bats.

Host traits and phylogeny can determine infection risk by driving pathogen transmission and its ability to infect new hosts. Predicting such risks is critical when designing disease mitigation strategies, and especially as regards wildlife, where intensive management is often advocated or prevented by economic and/or practical reasons. We investigated Pseudogymnoascus [Geomyces] destructans infection, the cause of white-nose syndrome (WNS), in relation to chiropteran ecology, behaviour and phylogenetics.

White-nose syndrome and wing damage index scores among summer bats in the northeastern United States.

White-nose syndrome (WNS) adversely affects millions of bats hibernating in caves of the eastern United States. Beginning in 2009, the US Fish and Wildlife Service supported use of a wing damage index (WDI) scoring system (scale of 0 to 3, or no damage to severe) to assess wing damage of bats captured during summer. Based on bat captures at 459 mist net sites in Pennsylvania, New York, Maryland, Virginia, and New Jersey, USA, we questioned whether WDI scores varied by species group, date, and distance to the closest known affected hibernaculum.

Thermocron iButton and iBBat temperature dataloggers emit ultrasound.

Thermocron iButton dataloggers are widely used to measure thermal microclimates experienced by wild animals. The iBBat is a smaller version of the datalogger, also commercially available, that is used to measure animal skin or core body temperatures when attached externally or surgically implanted. Field observations of bats roosting under a bridge suggested that bats avoided locations with iButtons.

Energy availability influences microclimate selection of hibernating bats.

Many species hibernate to conserve energy during periods of low food and water availability. It has long been assumed that the optimal hibernation strategy involves long, deep bouts of torpor that minimize energy expenditure. However, hibernation has ecological (e.