Presence of disease vector Bursaphelenchus xylophilus in Monochamus beetles as a function of spatial and temporal distance to fire

Beetles of the genus Monochamus are wood boring beetles of the family Cerambycidae. They are native to the front range of Colorado and through their xylophagous feeding on conifers, are also vectors of the pine wilt disease. Monochamus host the pine wood nematode(Bursaphelenchus xylophilus) which spreads the disease when it escapes its host and enters the tree tissues. Monochamus are thought to be pyrophilous, or attracted to weak, dead, or dying trees after wildfire disturbance. Therefore, they have an essential role in furthering succession through decomposition after fire. However, it is still unclear if the attraction to wildfire by Monochamussignificantly impacts transmission rate of the vectored disease in areas closer to fire in distance and/or time. Beetle assemblages of two native species (Monochamus clamator and Monochamus scutellatus) were sampled in Colorado lower montane forests in Larimer and Boulder counties, predominated by Ponderosa Pine. We chose twotransects ranging 0-15 km from the Cameron Peak and Calwood Fires of 2020 respectively. The 20 sampling sites were chosen to reflect a gradient of distance from the fires. Based on size and proximity to the sampling sites, we mapped 6 additional fires of various distances and ages. Overall, 8 fires were considered. After beetles were collected weekly over one flight season in 2021, they were identified, sorted, and examined for the presence of B.xylophilus by conducting fluorescence assays. Here, we explore how increasing spatial and temporal distances predict the frequency of B. xylophilus in Monochamusbeetles in Colorado.