DATA FOR: Body temperature rebounds on sea ice and is elevated by mercury contamination in a keystone predator

We used triaxial accelerometers (Axy 4, Technosmart, 3g) to collect detailed behavioral records from little auks (Alle alle) at Ukaleqarteq, East Greenland (70°44′N, 21°35′W), during the chick rearing period (July) of 2020. Simultaneously during this period, we assessed variation in the core (abdominal) body temperature (T_b) of 8 individuals, using T_b loggers (BodyCap Anipill Core Body Temperature Ingestible Tablet; BMedical; ±1°C), a telemetric system for gastrointestinal temperature recording. We also obtained small ~0.2-0.5 ml blood samples from the brachial veins of focal individuals to measure contamination from a potent chemical contaminant, mercury (Hg), and obtained detailed information regarding weather conditions (temperature, wind speed, relative humidity) from a station at the study site. We assessed how T_b varies with different behavioral states and environmental conditions, and additionally evaluated whether Hg concentrations independently affected T_b, or altered state-dependent changes in T_b. This dataset contains information regarding the body temperature (T_b), recorded at 1-min intervals. For each 1-min interval, associated information regarding behavior, from the accelerometer, and weather conditions, from the weather station is also given. In addition, for each individual, we provide Hg concentrations measured in erythrocytes and morphometric measurements.