Great white butterfly activity could pick up in the coming months and DOC are calling for people to find the last of the pests to bring the number down to zero.
The butterfly has not been detected for three months but DOC’s Great White Butterfly Project Manager Michael Shepherd says autumn is a peak period for great white butterfly breeding so sightings may rise.
She says they are at a critical stage for the programme to eradicate the pest butterfly.
“It’s encouraging to have had no great white butterfly detections in Nelson since an adult male was caught on 16 December but some great white butterflies stay dormant as pupae through the summer heat. The butterflies start emerging from pupae from now and start to breed.”
She says It’s crucial all the great white butterfly eggs, caterpillars, pupae and butterflies are found and destroyed to suppress breeding and eliminate the last of the pests.
“Our eradication team will continue searching gardens for butterfly infestations but we are also counting on the public to look for great white butterflies and their eggs, caterpillars and pupae and to report any found to the Ministry for Primary Industries hotline 0800 80 99 66.”
It was confirmed in December that the pest butterfly population had been knocked down to a low level. The current ‘mop-up’ phase will be followed by a ‘surveillance’ phase, with garden searches continuing to confirm the butterfly has been eradicated.
The eradication project was launched in November 2012 to clear the butterfly from Nelson-Tasman, the only region it is found. The butterfly poses a threat to endangered native cresses and to commercial and home brassica crops, including dairy and sheep farm crops.
