Risk assessment procedures for biological control agents in New Zealand: two case studies for generalists

New Zealand’s indigenous and productive ecosystems are highly vulnerable to invasive species: therefore, New Zealand has stringent biosecurity legislation which encompasses the introduction of new biological control agents. To introduce a new agent, an application is made to the Environmental Protection Authority (EPA). The risk assessment carried out by the applicant is reviewed and a decision is made by an independent committee following public submissions and Māori consultation. An application will be declined if it is likely the new agent will cause significant adverse impacts on any indigenous species within its natural habitat, on natural habitats or on New Zealand’s inherent genetic diversity. Contrasting case studies are presented on two generalist arthropod biological control agents, one for a predatory mirid Macrolophus pygmaeus (Rambur) (Hemiptera: Miridae) where the application was declined, and the other a predatory mite Neomolgus capillatus (Kramer) (Acarina: Bdellidae) which was considered for an application.