Hibernating female big brown bats (Eptesicus fuscus) adjust huddling and drinking behaviour, but not arousal frequency, in response to low humidity

Many mammals hibernate during winter, reducing energy expenditure via bouts of torpor. The majority of a hibernator’s energy reserves are used to fuel brief, but costly, arousals from torpor. Although arousals likely serve multiple functions, an important one is to restore water stores depleted during torpor. Many hibernating bat species require high humidity, presumably to reduce torpid water loss, but big brown bats (Eptesicus fuscus) appear tolerant of a wide humidity range. We tested the hypothesis that hibernating female E. fuscus use behavioural flexibility during torpor and arousals to maintain water balance and reduce energy expenditure. We predicted: (1) E. fuscus hibernating in dry conditions would exhibit more compact huddles during torpor and drink more frequently than bats in high humidity conditions; and (2) frequency and duration of torpor bouts and arousals, and thus, total loss of body mass would not differ between bats in both environments. We housed hibernating E. fus..., , , # Hibernating female big brown bats (Eptesicus fuscus) adjust huddling and drinking behaviour, but not arousal frequency, in response to low humidity

## Description of the data and file structure

The excel file has four different sheets that contains (listed in order):

**Sheet1_Video Data - arousals**: arousal begin and end time/date, bat ID, humidity treatment, drinking bouts, and associated starting body mass (prior to hibernation) and ending body mass (end of hibernation))

**Sheet2_Video Data - torpor:** torpor begin and end time/date, bat ID, humidity treatment, and associated starting body mass (prior to hibernation) and ending body mass (end of hibernation))

**Sheet3_Arousal Definition Data**: bat ID, humidity treatment, arousal begining and end data/time, and associated skin temperature threshold. Note: arousals for video data do not have an associated skin temperature threshold.

**Sheet4_Huddle Size Index**: photo date and time, humidity treatment, file name, and huddle ...