UC Davis

SummaryVan der Wal et al. (2015) (henceforth VdW) attempted to evaluate the degree to which the geographical origin of a species shapes people's attitudes towards conservation management decisions. Based on questionnaire surveys of the general public and experts from Scotland and Canada, the authors perceive “widespread use of the label ‘non-native’ as a proxy for harmfulness” and a species' origin as being used as shorthand for “harmfulness” (pp. 349 & 352). However, the authors cited by VdW do not take such a categorical view. Invasions of non-native species are also often just symptoms, not causes of human-created environmental changes. VdW focus on well-known species with long introduction histories for which the potential abundance and impact can plausibly be judged by experts and the public alike. However, when a decision is to be made regarding whether a non-native taxon that is not yet present in the local biota should be introduced, or whether a recently established and geographically restricted but spreading non-native taxon should be controlled, the taxon's origin should be a primary component in the decision-making process.