An inexpensive setup for robust activity tracking in small animals: Portable Locomotion Activity Monitor (pLAM)

Sondhi, Y.; Jo, N. J.; Alpizar, B.; Markee, A.; Dansby, H. E.; Currea, J. P.; Ruiz, C.; Fabian, S. T.; Barredo, E.; Degennaro, M.; Kawahara, A. Y.; Theobald, J. C.

doi:10.1101/2021.08.21.457197

bioRxiv · 10.1101/2021.08.21.457197

An inexpensive setup for robust activity tracking in small animals: Portable Locomotion Activity Monitor (pLAM)

Sondhi, Y.·Jo, N. J.·Alpizar, B.·Markee, A.·Dansby, H. E.·Currea, J. P.·Ruiz, C.·Fabian, S. T.·Barredo, E.·Degennaro, M.·Kawahara, A. Y.·Theobald, J. C.

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Abstract

O_LIAdvances in computer vision and deep learning have automated animal behaviour studies that previously required tedious manual input. However, tracking activity of small and fast flying animals remains a hurdle, especially in a field setting with variable light conditions. Commercial locomotor activity monitors (LAMs) can be expensive, closed source, and generally limited to laboratory settings. C_LIO_LIHere, we present a portable locomotion activity monitor (pLAM), a mobile activity detector to quantify small animal circadian activity. Our setup uses inexpensive components, is based on open-source motion tracking software, and is easy to assemble and use in the field. It runs off-grid, supports low-light tracking with infrared lights, and can implement arbitrary light cycle colours and brightnesses with programmable LEDs. We provide a user-friendly guide to assembling pLAM hardware and accessing its pre-configured software and guidelines for using it in other systems. C_LIO_LIWe benchmarked pLAM for insects under various lab and field conditions, then compared results to a commercial activity detector. They offer broadly similar activity measures, but our setup captures flight and bouts of motion that are often missed by beam-breaking activity detection. C_LIO_LIpLAM will enable high-throughput quantification of small animal location and activity in a low-cost and accessible manner, crucial to studying behaviour that can help inform conservation and management decisions. C_LI

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Sondhi, Y., Jo, N. J., Alpizar, B., Markee, A., Dansby, H. E., Currea, J. P., Ruiz, C., Fabian, S. T., Barredo, E., Degennaro, M., Kawahara, A. Y., Theobald, J. C.. 2021-08-23. An inexpensive setup for robust activity tracking in small animals: Portable Locomotion Activity Monitor (pLAM). https://doi.org/10.1101/2021.08.21.457197

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