The usefulness of the ecoregion concept for safer import of invertebrate biological control agents.

Abstract

From a scientific perspective it is clear that ecological boundaries are more relevant than national boundaries when assessing the hazards and risks of non-target effects of biological control agents, including invertebrate biological control agents (IBCAs). Different published approaches to categorizing terrestrial ecoregions are introduced and discussed. Movement of species between countries in the same ecoregion is clearly less risky than moving species between disjunct similar ecoregions, and the risk increases the further the separation between disjunct similar ecoregions, e.g. whether on the same continent or on different continents. The implications for movement of IBCAs within Europe are discussed in light of ecoregion classifications and examples of natural and human-mediated spread of introduced insects in the same region. In order to safely regulate the introduction of biological control agents, there needs to be consultation within an ecoregion. An ecoregion approach can be useful in predicting the likelihood that a classical IBCA will become established, but cannot robustly predict that an inundative IBCA will fail to become established. An ecosystem approach can be useful for assessing and managing risks associated with moving organisms within a contiguous land mass.