Climate warming changes synchrony of plants and pollinators

Climate warming changes the phenology of many species. When interacting
organisms respond differently, climate change may disrupt their
interactions and affect the stability of ecosystems. Here, we used GBIF
occurrence records to examine phenology trends in plants and their
associated insect pollinators in Germany since the 1980s. We found strong
phenological advances in plants, but differences in the extent of shifts
among pollinator groups. The temporal trends in plant and insect
phenologies were generally associated with interannual temperature
variation, and thus likely driven by climate change. When examining the
synchrony of species-level plant-pollinator interactions, their temporal
trends differed among pollinator groups. Overall, plant-pollinator
interactions become more synchronized, mainly because the phenology of
plants, which historically lagged behind that of the pollinators,
responded more strongly to climate change. However, if the observed trends
continue, many interactions may become more asynchronous again in the
future. Our study suggests that climate change affects the phenologies of
both plants and insects, and that it also influences the synchrony of
plant-pollinator interactions.