Torpor use in the wild by one of the world's largest bats
Data files
Jun 11, 2024 version files 1.93 MB
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ghff_winterdata.csv
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README.md
Abstract
Torpor is widespread among bats, presumably because most species are small and torpor greatly reduces their high mass-specific resting energy expenditure, especially in the cold. Torpor has not been recorded in any bat species larger than 50 g, yet in theory could be beneficial even in the world's largest bats (flying foxes; Pteropus spp.) that are exposed to adverse environmental conditions associated with energy bottlenecks. We used temperature telemetry to measure body temperature in wild-living adult male grey-headed flying foxes (P. poliocephalus; mean body mass: 799 g) during winter in southern Australia. We found that all individuals used torpor while day-roosting, with body temperatures as low as 27 °C. Torpor was recorded during cold, wet, and windy weather, strongly suggesting it is an adaptation to reduce energy expenditure during periods of increased thermoregulatory costs and depleted body energy stores. Our study has implications for our understanding of the distribution, behavioural ecology, and life history of flying foxes. Furthermore, our discovery increases the body mass of bats known to use torpor by more than tenfold and extends the documented use of this energy-saving strategy under wild conditions to all bat superfamilies, with important implications for the evolutionary maintenance of torpor among bats and other mammals.
README: Torpor use in the wild by one of the world's largest bats
https://doi.org/10.5061/dryad.zgmsbccm8
Description of the data
We have submitted our raw data (ghff_winterdata.csv). Data on core body temperature were calculated from pulse intervals of temperature-sensitive radio transmitters implanted in each bat recorded by receiver stations located in the roosting camp. Data on body temperature were recorded when bats were within approximately 200 m of the receiver stations (i.e., at the roosting camp). Data on weather variables were sourced from a weather station (#023000) of the Australian Bureau of Meteorology (BoM).
ghff_winterdata
Variables:
- bat identity: a unique identifier for each bat
- body temperature: (°C) core body temperature calculated from pulse intervals of temperature-sensitive radio transmitters implanted in each bat recorded by receiver stations located in the roosting camp. Data on body temperature were recorded when bats were within approximately 200 m of the receiver stations (i.e., at the roosting camp)
- date time ACST: Date and time of each body temperature measurement (Time Zone: Australian Central Standard Time)
- precipitation: Accumulated rainfall (mm) over 1-minute intervals
- air temperature: Air temperature (°C)
- relative humidity: relative humidity (%)
- wind speed: wind speed (km/h)
- sea level pressure: air pressure at sea level (hPa)
- hour of day: time at the resolution of hour
- sunrise ACST: time of sunrise calculated for the city of Adelaide South Australia (Time Zone: Australian Central Standard Time)
- sunset ACST: time of sunset calculated for the city of Adelaide South Australia (Time Zone: Australian Central Standard Time)
- min from sunrise: minutes from the time sunrise calculated for the city of Adelaide South Australia (Time Zone: Australian Central Standard Time)
- min from sunset: minutes from the time sunset calculated for the city of Adelaide South Australia (Time Zone: Australian Central Standard Time)
- day or night: factor designating if time was between sunrise and sunset
- sex: factor designating whether an individual was male or female
- mass: mass of each individual measured at the time of capture (g)