What is the minimum possible timeframe for an incursion of an unwanted organism to be assessed and signed off by a Chief Technical Officer as an unwanted organism?

Answer

Under the Biosecurity Act 1993, an organism becomes an unwanted organism when a Chief Technical Officer forms the belief that the organism is capable or potentially capable of causing unwanted harm to any natural and physical resources or human health. In cases such as this response, the Chief Technical Officer takes advice and gathers knowledge from experts, including international experts who have dealt with the organism in question. The Chief Technical Officer weighs up the advice and knowledge against expectations on the impact to New Zealand (which may not be the same as overseas environments) before determining that an organism should be added to the Unwanted Organism register. However, in this instance the Ministry for Primary Industries (MPI) acted well before the Chief Technical Officer agreed to add yellow-legged hornets to the Unwanted Organism register on 11 November 2025. From 17 October 2025, MPI’s incursion investigators were undertaking operations under urgent measures until a formal MPI response was initiated on 3 November 2025.