Sites were chosen from Yosemite National Park maps. Larger meadows were prioritized and although most the meadows were within a day’s hike from a trailhead, several were tens of kilometers from the nearest road. Previous research (Morelli et al 2012 Proceedings of the Royal Society B) showed that detectability was very high (>95% with only one visit) so most sites were visited only one or two times although always with two experienced observers. Sites were surveyed on foot for at least 30 minutes during morning or evening hours. A site would be considered occupied if only one Belding’s ground squirrel was detected but in reality numerous individuals were detected at all occupied sites.
