Meeting Abstract
Hibernation research often focusses on extreme hibernation phenotypes associated with long periods of hibernation. At high latitudes, bats may approach their physiological limits as they deposit large fat stores and use long torpor bouts to survive long winters. However, more southern populations may not hibernate in the same way. As part of a larger project examining the implications of white-nose syndrome for bats in Western North America, we examined the behavior and physiology of hibernating Myotis velifer in Western Oklahoma where winter is comparatively short. We used quantitative magnetic resonance to measure body composition, respirometry to determine torpid metabolic rate, radiotelemetry to record torpor arousal dynamics, acoustic monitoring for activity outside the hibernaculum, and recorded temperature and humidity throughout the hibernaculum. Despite the relatively short winter, M. velifer deposited large fat stores comparable to those at northern latitudes, and did so in a sex-biased manner. Bats remained relatively active throughout much of the winter, except during notable weather events, and roosted in areas that did not correspond to minimum metabolic rate. This study suggests M. velifer fall on the other end of the hibernation phenotype spectrum. Winter is comparatively mild, but bats deposit large energy stores that enable them to hibernate in a manner that does not minimize energy expenditure. With these field data, we are currently developing bioenergetic models to predict the impact of white-nose syndrome in this species and others across the West.
