Thermal Ethology: Staying Warm is not the Norm

I’m happy to report that our paper entitled “Staying warm is not the norm: Behavioural differences in thermoregulation in two snake species” is published in the Canadian Journal of Zoology at the following link:

Congratulations to the team in my lab for pulling this paper together.

In this study, we focus on laboratory measurements of behaviours (in two species of snakes) related to temperature regulation to highlight methodological approaches to studying thermoregulation in ectotherms.

Over the past few years, we have read a lot of papers that report on thermoregulation in ectotherms, but we have felt that critical information on whether the animals are purposely thermoregulating is missing. How do you know they are thermoregulating? Is it sufficient to simply examine their position within the thermal gradient? Perhaps the direction they orient is important to establishing their motivations? How do you know an ectotherm is thermoregulating rather than simply moving around at random? Maybe accounting for activity and exploration effects in these studies can help make a difference? These topics have been covered in a number of other papers from our laboratory (Wang et al 2019; Black and Tattersall, 2017; Black et al, 2019), but we test them here using two species of snakes with contrasting life histories, where we would expect different thermoregulatory preferences given the different microhabitats preferred in nature.

These are some of the questions we focus on in this study of the Eastern Garter Snake (Thamnophis sirtalis sirtalis) and the semi-fossorial Northern Red-bellied Snake (Storeria occipitomaculata occipitomaculata). While we do report that the semi-fossorial snakes appear to prefer cooler temperatures, please read the paper for some of the more subtle differences between these species.

Anyhow, we hope to convince fellow researchers to report on these sort of behaviours since they may likely be helpful in bolstering the case that the animal is motivated to select temperatures.

Video time lapse of a garter snake in a circular / doughnut shaped thermal gradient.

Thermal gradient used in the study.


Giacometti, D., Yagi, KT, Abney, CR, Jung, MP, and Tattersall, GJ. 2021. Staying warm is not always the norm: Behavioural differences in thermoregulation of two snake species. Canadian Journal of Zoology, Accepted, Aug 25 2021.

Many thanks to the co-authors in this study. This research was originally part of Curtis Abney’s MSc thesis, supplemented with Matthew Jung’s Honours thesis (with input and guidance from Dr. Katherine Yagi), and brought together by the fine analytical and writing skills of Danilo Giacometti.


Black, IRG and Tattersall, GJ. 2017.  Thermoregulatory behavior and orientation preference in bearded dragons.  Journal of Thermal Biology. 69: 171-177.;

Black, IRG, Berman, JM, Cadena, V, and Tattersall, GJ. 2019. Behavioral thermoregulation in lizards: Strategies for achieving preferred temperature. In: Behavior of Lizards: Evolutionary and Mechanistic Perspectives, Eds. Vincent Bels and Anthony Russell, CRC Press, 410 pp.

Wang, SYS, Tattersall, GJ, and Koprivnikar, J. 2019.  Trematode parasite infection affects temperature selection in aquatic host snails. Physiological and Biochemical Zoology. 92(1):71-79.