Plant-pollinator network response to high-severity fire along a gradient of time-since-disturbance

Native bees are critical components of ecosystems where they provide an estimated ~85% of pollination services. In recent decades, reports of a global decline in bee populations have drawn concern from conservationists, compelling the need for further research on the drivers and mechanisms influencing the diminishment of native bee populations. In ponderosa pine ecosystems, fire suppression policy implemented throughout much of the 19 th  century promoted dense stand structures with closed canopies, suppressed understories, and increased surface fuel loadings. Coupled with climate change, these conditions have led to exacerbated fire regimes often resulting in large-scale, high severity fire events. Though extant research has evidence supporting wildfire may have positive effects on bee communities, it remains unclear how wildfire impacts bee-plant networks and how long observed patterns persist on the landscape. To address this knowledge gap, bee-plant communities were sampled across two growing seasons within ponderosa pine-dominant forests of northern Colorado to assess effects of high-severity wildfires along a time-since-disturbance gradient. Findings here have implications for forest management and indicate structural elements of ecosystems that can be managed for enhancing bee biodiversity and provide insight into how future high-severity fire events may alter plant-pollinator networks in a time of shifting climate.