Animal ecology is shaped by energy costs, yet it is difficult to measure fine-scale energy expenditure in the wild. Because metabolism is often closely correlated with mechanical work, accelerometers have the potential to provide detailed information on energy expenditure of wild animals over fine temporal scales. Nonetheless, accelerometry needs to be validated on wild animals, especially across different locomotory modes.
We merged data collected on 20 thick-billed murres (Uria lomvia) from miniature accelerometers with measurements of daily energy expenditure over 24 h using doubly labelled water. Across three different locomotory modes (swimming, flying and movement on land), dynamic body acceleration was a good predictor of daily energy expenditure as measured independently by doubly labelled water (R2 = 0.73). The most parsimonious model suggested that different equations were needed to predict energy expenditure from accelerometry for flying than for surface swimming or activity on land (R2 = 0.81).
Our results demonstrate that accelerometers can provide an accurate integrated measure of energy expenditure in wild animals using many different locomotory modes.
TDR Acc+H2O: These are the time-depth recorder files (the .bin files are the binary files from the loggers; the .TXT are the converted files provided by the TAGTALK software.) Each folder is labelled with the individual ID (the band number) of the murre whose doubly-labelled water data appear in the data appendix. After a preamble generated by the software, the date-time, pressure (in dbar) and temperature are provided.
DEE calculations: Excel spreadsheet shows raw ppm values from blood samples used for measurement of energy expenditure using doubly-labelled water and equations used to convert those ppm values into energy expenditure. Also shown are calculated PDBA (partial dynamic body acceleration) values relative to measured energy expenditure. The "ID" is the band number that can be cross-referenced with the activity/accelerationd data.
Accelerometer data: Each bird (ID given by five digit band number) can be cross-referenced with TDR and DLW data in other files. Each bird has a depth (in m), temperature, X-axis acceleration (in g) and Y-axis acceleration (in g) file following a preamble describing the time when the logger was started. All data is given in 1-s (depth/temperature) or 16 Hz (acceleration) increments.
This work is licensed under a CC0 1.0 Universal (CC0 1.0) Public Domain Dedication license.
- thick-billed murre
- Uria lomvia