QUANTIFYING GREAT BASIN BUTTERFLY-POLLEN NETWORKS OVER A 100 -YEAR TIME SERIES

Plant-pollinator interactions are critical to long-term ecosystem function, and pollination is one of the best quantified ecosystem services. These interactions contribute substantially to biodiversity and are likely to provide ecosystem stability in the face of climate change and environmental stress. However, due to factors like climate change and habitat loss, pollinators are experiencing documented declines in many parts of the world. In this study, we utilized museum specimens as a novel source of data to understand changing plant-pollinator associations in the last decade in the Great Basin Desert. Here, we summarize pollen-insect quantitative networks gleaned from adult Lepidopteran museum specimens to characterize these interactions and to examine how richness and frequency of butterfly-pollen associations have changed over a 100-year time series. We estimated butterfly-pollen network parameters based on pollen collected from butterfly specimens from the Great Basin and Sierra Nevada. Butterfly-pollen networks indicated that most pollen-butterfly species interactions are specialized and appear to be more reticulate than observational networks. Interaction networks associated with specimens captured before and after 2000 revealed that compared to previous decades, butterfly-pollen networks over the past 20 years had higher nestedness and connectance, with high pollen richness and low pollen abundance. These findings illustrate a unique approach to understanding more about how pollination biology is changing in the Anthropocene.