Incorporating evaporative water loss into bioenergetic models of hibernation to test for relative influence of host and pathogen traits on white-nose syndrome

Autoři: Catherine G. Haase aff001;  Nathan W. Fuller aff002;  C. Reed Hranac aff003;  David T. S. Hayman aff003;  Liam P. McGuire aff002;  Kaleigh J. O. Norquay aff004;  Kirk A. Silas aff005;  Craig K. R. Willis aff004;  Raina K. Plowright aff001;  Sarah H. Olson aff005
Působiště autorů: Department of Microbiology and Immunology, Montana State University, Bozeman, Montana, United States of America aff001;  Department of Biological Sciences, Texas Tech University, Lubbock, Texas, United States of America aff002;  Molecular Epidemiology and Public Health Laboratory, Hopkirk Research Institute, Massey University, Palmerston North, New Zealand aff003;  Department of Biology, University of Winnipeg, Winnipeg, Canada aff004;  Wildlife Conservation Society, Wildlife Health Program, Bronx, New York, United States of America aff005
Vyšlo v časopise: PLoS ONE 14(10)
Kategorie: Research Article


Hibernation consists of extended durations of torpor interrupted by periodic arousals. The ‘dehydration hypothesis’ proposes that hibernating mammals arouse to replenish water lost through evaporation during torpor. Arousals are energetically expensive, and increased arousal frequency can alter survival throughout hibernation. Yet we lack a means to assess the effect of evaporative water loss (EWL), determined by animal physiology and hibernation microclimate, on torpor bout duration and subsequent survival. White-nose syndrome (WNS), a devastating disease impacting hibernating bats, causes increased frequency of arousals during hibernation and EWL has been hypothesized to contribute to this increased arousal frequency. WNS is caused by a fungus, which grows well in humid hibernaculum environments and damages wing tissue important for water conservation. Here, we integrated the effect of EWL on torpor expression in a hibernation energetics model, including the effects of fungal infection, to determine the link between EWL and survival. We collected field data for Myotis lucifugus, a species that experiences high mortality from WNS, to gather parameters for the model. In saturating conditions, we predicted healthy bats experience minimal mortality. Infected bats, however, suffer high fungal growth in highly saturated environments, leading to exhaustion of fat stores before spring. Our results suggest that host adaptation to humid environments leads to increased arousal frequency from infection, which drives mortality across hibernaculum conditions. Our modified hibernation model provides a tool to assess the interplay between host physiology, hibernaculum microclimate, and diseases such as WNS on winter survival.

Klíčová slova:

Bats – Bioenergetics – Fats – Fungal growth – Hibernation – Humidity – Winter


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