Abstract
Native pollinators are in decline across the globe, likely due to a combination of habitat loss, pesticides, invasive species and changing climate. Determining the independent effects of climate on pollinators has been difficult in part because we lack studies of pollinator populations in largely undisturbed areas. Early spring and alpine pollinators are most likely to be affected by changing climate. Using a standardized sampling protocol, I measured relative abundance of major pollinator groups (flies, beetles, bees, wasps, and butterflies) from early spring to late summer at sites ranging from 2100 to 3300 m elevation. Flies were most abundant in early spring and at high elevations. Bees were abundant throughout the season and across all elevations. These data suggest that flies and bees should be targeted for future monitoring because they may be particularly susceptible to changing climate, and their loss could cascade through the broader community.