Evaluating methods to quantify spatial variation in the velocity of biological invasions

Submitted by editor on 29 April 2016. Get the paper!
Close-up of horse chestnut leafminer, Cameraria ohridella. Hhoto credit: Gyorgy Csoka, Hungary Forest Research Institute, Bugwood.org


by Andrew Liebhold

When invasive species spread through heterogeneous regions, they typically spread faster in some regions than others, either as a result of geographical variation in conditions favoring population growth, or because of variation in rates at which individuals move. Understanding such geographical variation in rates of spread is important, both for predicting spread of species into new regions and for developing strategies to contain spread. I this paper, several different methods are compared for their ability to correctly identify spatial variation in invasion spread and relate that variation to characteristics of the local habitat. This is accomplished via simulating spread of hypothetical invasive species in which the geographical variation in spread rate is known. The same methods are also applied to historical data on the spread of an epidemic of bluetongue virus and of the horse-chestnut leafminer, Cameraria ohridella, both spreading through France during the 2000s. Specific recommendations are made on the performance of different methods of interpolating historical records of first detection records and application to measure spatial variation in rates of spread.

Damage caused by Cameraria ohridella. Photo credit: Fabio Stergulc, Università di Udine, Bugwood.org.