Modelling the flight trajectories of Monochamus galloprovincialis in heterogeneous landscapes
Résumé
Potential spread of the pine wood nematode (PWN), Bursaphelenchus xylophilus, is driven by both insect vector and human-mediated dispersal. At local scale, dispersal capacity of the vector may explain the failure of eradication measures such as host tree removal. In Europe, the PWN is transported by the pine sawyer beetle, Monochamus galloprovincialis. Although the insect is known to disperse at short distances following mark-release-recapture experiments, the insect is able to fly rather long distances on a flight mill (cumulated distance of 16 km on average and up to 63 km). A first dispersal model was developed to describe the flight trajectory of M. galloprovincialis in non-fragmented pine forests. The shape of the dispersal kernel was fitted to the data recorded in the flight mill experiment to capture the proportion of long-distance flights compared to short-distance flights. Then, the dispersal model was refined to flight distances recorded in the field using data from the mark-recapture experiments conducted in a pine forest. Here, we will present how this model was adapted to simulate the dispersal of the insect vector in heterogeneous landscapes, e.g. a mosaic of pines, broadleaf trees, and open areas. This model was fitted to recent data from other mark-release-recapture experiments in such diverse landscapes.