Dead-reckoning animal movements in R: a reappraisal using Gundog.Tracks

by Richard M. Gunner, Mark D. Holton, D. Michael Scantlebury, Carlos M. Duarte,
Research article Year: 2021 DOI:


Gunner, R. M., Holton, M. D., Scantlebury, M. D., van Schalkwyk, L., English, H. M., Williams, H. J., Duarte, C.M., ... & Wilson, R. P. (2021). Dead-reckoning animal movements in R–A reappraisal using Gundog. Tracks.


Fine-scale data on animal position are increasingly enabling us to understand the details of animal movement ecology and dead-reckoning, a technique integrating motion sensor-derived information on heading and speed, can be used to reconstruct fine-scale movement paths at sub-second resolution, irrespective of the environment. On its own however, the dead-reckoning process is prone to cumulative errors, so that position estimates quickly become uncoupled from true location. Periodic ground-truthing with aligned location data (e.g., from global positioning technology) can correct for this drift between Verified Positions (VPs). We present step-by-step instructions for implementing Verified Position Correction (VPC) dead-reckoning in R using the tilt-compensated compass method, accompanied by the mathematical protocols underlying the code and improvements and extensions of this technique to reduce the trade-off between VPC rate and dead-reckoning accuracy. These protocols are all built into a user-friendly, fully annotated VPC dead-reckoning R function; Gundog.Tracks, with multi-functionality to reconstruct animal movement paths across terrestrial, aquatic, and aerial systems, provided within the Additional file 4 as well as online (GitHub).