Instead, isolated colonies become established beyond the population front mostly because of inadvertent transportation of life stages by humans. As isolated colonies grow, they coalesce and contribute to the expansion of the population front. The rate of spread can be reduced if isolated colonies in the transition zone are detected and eradicated before they grow too large. Spread of gypsy moth populations via establishment of isolated colonies beyond the advancing front. The following decision-support system for the STS project has been evolved during the initial pilot project.
Project area is a barrier zone set along the expanding population front.
Sharov et al. However, averaging of population boundaries in time was not tested. The action zone is used for detecting and eradicating of isolated colonies whereas the monitoring zone is used for delineating population boundaries which are necessary for determining the location of the project area and for evaluating the effect of the project on the rate of population spread. The width of the action zone is a constant and is equal to 100 km. Shading represents moth counts in pheromone traps.