2013 Research Highlights
Forest Pest Risk Maps Reveal Uncertainties
Novel techniques make maps more useful for decision support
Scientists and collaborators with the Eastern Forest Environmental Threat Assessment Center have pioneered new methods for the representation of uncertainty in invasive species risk maps, improving the maps’ utility for decision support. Pest risk maps are intended to show decision makers which locations in their regions of concern face the greatest risk of invasion by a pest, allowing decision makers to prioritize use of scarce resources for monitoring and management. Uncertainty is an inevitable aspect of the risk mapping process, as it arises from sources including the spatial data used to make the map as well as the parameter values of the model used to construct the map. Commonly, these various uncertainties are downplayed or omitted from final risk map products, which may lead map users to make incorrect management decisions.
In a recent article in the journal Diversity and Distributions, researchers presented new techniques that directly incorporate uncertainties into final risk estimates. The invasion risk and corresponding uncertainty values are integrated in a single map product. In particular, a technique demonstrated by researchers ranks all locations in a map from the perspective of a risk-averse decision maker, who generally assigns higher management priority to locations where the risk of invasion is more certainly known. In short, under a risk-averse perspective, the estimated invasion risk is discounted according to the degree of uncertainty in that estimate. The outlined techniques should be applicable to a variety of pest risk modeling and mapping approaches.
Right: Adult emerald ash borers emerge from an ash tree. Photo by Debbie Miller, USDA Forest Service, Bugwood.org
External Partners/Collaborators: Canadian Forest Service; Canadian Food Inspection Agency; University of New Hampshire
Contact: Frank Koch, Eastern Threat Center research ecologist, (919) 549-4006, frank.h.koch@usda.gov
