The risk of diapausing pest insects on pathways to NZ

This research will deliver critical, currently unavailable, knowledge on the risk of diapausing high-risk pest insects on pathways to New Zealand, and how New Zealand’s climate change predictions may affect this risk.

This information will be made available for use by MPI and industry to support future risk assessments of diapausing high-risk pest insects.  The new knowledge obtained in this project will provide evidence to inform development of cross-sector (incl. Māori) biosecurity measures to minimize the risk of diapausing pest insects entering New Zealand in a viable/active state.

The research team conducted an extensive literature review in 2022-2023 to identify knowledge gaps and opportunities related to diapause of high-risk pest insects (e.g., Spotted Lanternfly, Spongy moth, Tobacco hornworm, Khapra beetle, Brown Marmorated Stink Bug) on pathways to New Zealand. The literature review addressed generic obligate and facultative diapause (at egg, juvenile, and adult stages), if diapause affects the likelihood of the insects being on the pathway, surviving the journey, and establishing in New Zealand purely based on their biology and physiology. The review also explored how climate change predictions for New Zealand will impact (positively or negatively) on the risk posed.

Researchers worked closely with stakeholders and end-users to determine the list of insect species to focus on, so different insect orders were addressed, as well as diapause in the different life stages. At a workshop in May 2023, end-users and stakeholders decided there were still too many variables at play, so the risk to New Zealand is still high. Research to address the critical gaps was formulated for 2023-2024.

Contact Project Leader Jessica Vereijssen: jessica.vereijssen@plantandfood.co.nz