Date: 12 November 2013
The Department of Conservation is asking Nelson Tasman people to check their caravans, campervans and trailers for great white butterfly pupae (chrysalises) before heading away on trips to avoid spreading the major pest elsewhere.
Anyone finding the butterfly’s greyish-white or pale green pupae on board is asked to report it to the Ministry for Primary Industries (MPI) Exotic Pest and Diseases hotline 0800 80 99 66. DOC staff will then respond.
Greyish-white butterfly pupa
Vehicle testing agencies, including VTNZ, VINZ and AA, are giving support with staff at their Nelson stations checking caravans, campervans and trailers for pupae during warrant of fitness checks.
DOC is attempting to eradicate the great white butterfly in Nelson Tasman and stop it spreading to other parts of New Zealand. The butterfly poses a serious threat to endangered native cresses and home and commercial brassica crops, including crops to feed farm cattle and sheep.
DOC Great White Butterfly Project Manager Martyn King said vehicles leaving the Nelson Tasman region with pupae on board were a major risk for spreading the pest butterfly elsewhere.
Pale green pupa
‘We need the Nelson Tasman community’s help in ensuring the great white butterfly remains within the Nelson Tasman region so we have a chance of eradicating it and stopping it becoming a widespread pest in New Zealand. This includes making sure before leaving home that any caravans, campervans and trailers being taken away have no pupae on board.
‘Caravans, campervans and trailers are often parked up in gardens over winter, providing a convenient environment for great white butterfly caterpillars to crawl onto to pupate.
‘The best way to check caravans, campervans and trailers is to start at the top, working your way around the vehicle, particularly checking overhangs like windowsills and awning tracks, and then looking underneath around wheel arches.
‘Great white butterfly pupae sit flat on surfaces. They are often in hidden spots such as inside rims.’
The pupae are 25 mm long, distinctively dotted with yellow and black spots and have blunt-spiked ridges. The greyish-white form is most commonly found on vehicles.
Mr King said the DOC butterfly eradication team was very grateful for the high support being given by Nelson householders for its intensive garden searching to suppress a spring butterfly breeding surge.
‘With up to 25 staff working each day, we have carried out more than 13,500 garden searches for caterpillars and eggs so far this spring.’
Nelson Tasman householders are asked to look for the caterpillars and eggs and report any found to the MPI hotline 0800 80 99 66. The caterpillars and eggs can be found on the butterfly’s favoured plants including nasturtium, honesty and brassica vegetables such as cabbage and broccoli. People are also asked to kill the adult butterflies.
Project Manager, Nelson District Office
Phone: +64 3 546 3189
DOC Communications Advisor
Phone: +64 3 546 3146