2964 (2026). Hon Jo Luxton to the Minister for Biosecurity

2964 (2026). Hon Jo Luxton to the Minister for Biosecurity: What, if any, calcium isotope testing has been conducted in waterways adjacent to, or near, known Corbicula fluminea infestations to detect early spread, including sampling locations, dates of sampling, and measured calcium isotope levels over time?

Hon Andrew Hoggard: I am advised that Earth Sciences New Zealand and Lincoln Agritech are undertaking programmes of research to better understand current and potential impacts of Corbicula fluminea on water chemistry in New Zealand. The research involves testing for dissolved calcium levels; a reduction would indicate increased uptake by clams. I am advised that further information on this testing is held by Earth Sciences New Zealand.