Living on the edge: Ecology of a suburban western terrestrial garter snake (Thamnophis Elegans) population

There is modicum of literature describing the gestational behaviour and habitat selection of northern reptiles, even less so in urban-centered areas such as city parks. Over parts of its range, the Western Terrestrial Garter Snake (Thamnophis elegans) appears to be relatively successful at persisting in areas with considerable human activity, such as parks. This study will provide crucial insight on how snake species may persist in areas subject to various amounts of developments – particularly during periods of extreme weather and a rapidly changing climate. My study used mark-recapture and telemetry to gather population and behavioural data of T. elegans in a municipal park in Kamloops, British Columbia Canada. The park sits on the current edge of the city, with suburban neighbourhoods to the north and northeast, a busy highway to the west, and ranchlands to the south. I caught 30 snakes throughout the course of the summer (4 recaptures) with the most success occurring at the start of the field season (May, June, and early July) and the least amount of success mid-July onward. Distribution of snakes was split between three locations with minimal intermingling of snakes between locations, but I was unable to determine which factor(s) (extreme heat, transmitter injury, or other) limited their movements to other microsites within the park. Body condition (body mass in relation to length) were consistent across the range of sizes I sampled. Female:male snakes were caught at a ratio of 1:1.7, which may reflect males being easier to catch, or that females generally were more cryptic. I used Radiotelemetry to follow five snakes throughout the park with the initial goal of identifying overwintering and communal gestation (rookery) sites. I was unsuccessful on both counts, with a record-setting heatwave possibly altering gestational behaviour by the females. Complications also prevented me from tracking any snake to a specific hibernaculum, but general directional movements toward putative denning site(s) were documented, which suggest a location outside the park boundary is likely where the snakes overwinter. This work provides baseline population data for The City of Kamloops and a framework for future research on this northern suburban snake population.