Water temperatures inside a swamp white oak tree hibernaculum used by spotted turtles, and at the bottom of the pool outside the tree, recorded every 30 minutes from December 2020 through mid–March 2021 with a Hobo U12-008 data logger and TMC temperature sensors (Onset Computer, Pocasset, MA). Sensors were placed at the bottom of the pool inside the tree (verified with the endoscopic camera) and at the bottom of the center of the pool outside the tree.