Ultra-light photosensor collars to monitor Arctic lemming activity

David Bolduc; Dominique Fauteux; Éric Bharucha; Jean-Marie Trudeau; Pierre Legagneux

doi:10.1186/s40317-022-00302-1

Ultra-light photosensor collars to monitor Arctic lemming activity

Anim Biotelemetry. 2022;10(1):31. doi: 10.1186/s40317-022-00302-1. Epub 2022 Oct 11.

Authors

David Bolduc¹, Dominique Fauteux^{1

2}, Éric Bharucha^{1

3}, Jean-Marie Trudeau^{1

3}, Pierre Legagneux¹

Affiliations

¹ Centre d'Études Nordiques, Université Laval, 1045, avenue de la Médecine, Québec, QC G1V 0A6 Canada.
² Centre for Arctic Knowledge and Exploration, Canadian Museum of Nature, P.O. Box 3443 station D, Ottawa, ON K1P 6P4 Canada.
³ Sentinel North Technological Instrument Development Platform, Université Laval, 2375 rue de la Terrasse, Québec, QC G1V 0A6 Canada.

Abstract

Background: Studying the anti-predatory behavior of mammals represents an important challenge, especially for fossorial small mammals that hide in burrows. In the Arctic, such behaviors are critical to the survival of lemmings considering that predation risks are high every summer. Because detailed information about how lemmings use burrows as hideouts is still lacking, we developed a 1.59 g photosensitive collar to record any event of a small mammal moving between a dark area (e.g., burrow) and a bright area (e.g., outside the burrow). Tests of how collars affected lemming behavior were conducted in captivity in Cambridge Bay, Nunavut, Canada, in November 2019 and field tests were conducted on Bylot Island, Nunavut, Canada, in August 2021.

Results: The device was made of two chemical batteries and a printed circuit board (PCB) equipped with a photosensor and a real-time clock that recorded amplitude transient thresholds of light (lux) continuously. In accordance with ethical use of such devices, we verified that no abnormal loss of body mass was observed in captive or free-ranging lemmings, and no difference in recapture rates were observed between those with and without a collar, though we could not test this for periods longer than 108 h. Measurements of light intensities revealed consistent patterns with high lux levels at mid-day and lowest during the night. Lemmings showed clearly defined behavioral patterns alternating between periods outside and inside burrows. Despite 24-h daylight in the middle of the summer, August nighttime (i.e., 11 PM to 4 AM) lux levels were insufficient for amplitude transient thresholds to be reached.

Conclusion: By taking advantage of the long periods of daylight in the Arctic, such technology is very promising as it sets new bases for passive recording of behavioral parameters and builds on the prospect of further miniaturization of batteries and PCBs.

Keywords: Dicrostonyx groenlandicus; Dicrostonyx hudsonius; Lemmus trimucronatus; Light sensor; Modern ethology; Predator refugia; Subterranean.