“…Although body condition explained most of the intraspecific variation in hibernation immergence timing in northern Idaho ground squirrels, we found some support for the thermal tolerance and food limitation hypotheses in regard to emergence timing. Both the negative effect of acute temperature and positive effect of snowmelt date on emergence date in the spring after squirrels were collared corroborate many past studies of temperate zone hibernators (Goldberg & Conway, 2021;Kucheravy et al, 2021;Lane et al, 2012;Meyer et al, 2016;Michener, 1977;Murie & Harris, 1982;Pigeon et al, 2016;Sheriff et al, 2011;Tamian et al, 2022;Turbill & Prior, 2016;Williams et al, 2017), suggesting the most common hypotheses invoked to explain variation in hibernation behaviour-thermal tolerance and food limitation-do influence hibernation phenology, though less so than predation and sexual selection in our system. Additionally, expected peak NDVI at a given study site-a measure of future forage availability-negatively affected hibernation emergence date and duration.…”