http://creativecommons.org/licenses/by/4.0/ Typically, large ungulates show a single seasonal peak of heart rate, a proxy of energy expenditure, in early summer. Different to other large ungulates, wild boar females had peak heart rates early in the year (at ~ April, 1), which likely indicates high costs of reproduction. This peak was followed by a trough over summer and a secondary summit in autumn/early winter, which coincided with the mast seeding of oak trees and the mating season. Wild boars counteracted the effects of cold temperatures by decreasing subcutaneous body temperature by peripheral vasoconstriction. They also passively gained solar radiation energy by basking in the sun. However, the shape of the seasonal rhythm in HR indicates that it was apparently not primarily caused by thermoregulatory costs but by the costs of reproduction. Wild boar farrow early in the year, visible in high HRs and sudden changes in intraperitoneal body temperature of females. Arguably, a prerequisite for this early reproduction as well as for high energy metabolism over winter is the broad variety of food consumed by this species, i.e., the omnivorous lifestyle. Extremely warm and dry summers, as experienced during the study years (2017, 2018), may increasingly become a bottleneck for food intake of wild boar. Supporting Information to the article Ruf, T, Vetter, SG, Painer, J, Stalder, G, Bieber, C (2021) Atypical for northern ungulates, energy metabolism is lowest during summer in female wild boars (Sus scrofa). Scientific Reports, 11, DOI: 10.1038/s41598-021-97825-z Supplementary Methods on animals and surgery as well as activity recording. Supplementary Fig. S1: Heart rates of 10 adult, female wild boar over the course of one year. Hourly means including both rest and activity as subjected to GAMM analysis. Dati Altro 2021 Springer Nature © 2021. The Author(s). open access eng Data other Open Access application/pdf Heart rate energy metabolism season acclimatization thermoregulation basking Scientific Reports Atypical for northern ungulates, energy metabolism is lowest during summer in female wild boars (Sus scrofa) : Supporting Methods & Fig. S1 Thomas Ruf Sebastian G. Vetter Johanna Painer Gabrielle Stalder Claudia Bieber Daten sonstige https://phaidra.vetmeduni.ac.at/o:5330