Stink bug insect is enemy number one

It is a stinky brown insect the size of a 10c coin and last year it cost one car importing company

$19 million.

The brown marmorated stink bug is regarded as New Zealand’s number one pest threat, which if established could knock

$3.6 billion from the economy over 20 years.

Vehicle Industry Association chief executive David Vinsen said ships had to be turned away from the Ports of Auckland last year because they were found to have the voracious stink bugs on board. ‘‘It was extremely expensive to send them away to Australia and Singapore for fumigation and bring them all back.’’

The measures are an indication of the seriousness with which Biosecurity NZ (an arm of the Ministry for Primary Industries) is taking the threat of the bug, a native of Asia but which has now spread to the United States and Europe.

It feeds on more than 300 host plants, including citrus, pipfruit, stonefruit, berries and grapes, corn, honeysuckle and roses.

In New Zealand’s benign, temperate climate it would thrive.

MPI’s chief quarantine officer for the Ports of Auckland, Erin McElhannan, said 33 countries now have to take measures to stop the bug before it reaches New Zealand shores. In the case of Japan, the source of most vehicles, three importing companies had to spend millions on heat treatment plants.

Vinsen said three border inspection organisations that are accredited by MPI in Japan decided they needed to invest in the technology. ‘‘By the beginning of September last year they were in a position to have the plants ready for the start of the season,’’ Vinsen said.

The ‘‘season’’ signifies period when the bugs in the the

The brown marmorated stink bug has more than 300 host plants it can eat. Left, release of the samurai wasp has been preapproved to control the stink bug.

northern hemisphere are searching for places to winter over, and stretches from October to April.

They were first noticed arriving in machinery parts and vehicles from the US in 2012, and later from Italy, until the emergency in February last year when the ships from Japan loaded with cars had to be turned back from Auckland. ‘‘Last season we intercepted 3483 at the border,’’ McElhannan said. ‘‘Most were in containers, vehicles and parts.

‘‘We had one find Mt Maunganui and one in in

Erin McElhannan

MPI chief quarantine officer for the Ports of Auckland

Glenfield but nothing established.

‘‘It is difficult to say how they arrived because they were not associated with any cargo,’’ McElhannan said.

She hoped the heat treatment would suffice but fumigation was a backup option if any bugs were discovered on ships once they arrived in New Zealand.

MPI entomologist Catherine Duthie said she was ‘‘deeply invested’’ in the stink bug project, so much so that she has an image of the pest tattooed on her arm.

‘‘I have been following this project for eight years. Every year we manage to keep the bug out is a year that we have to prepare for the eventual detection.

‘‘The real risk comes with aggregations, so a single bug in someone’s suitcase is not really a risk, they are not reproductively active in this overwintering state.

‘‘It is only when you get a bunch of them together, they start feeding and then mature sexually, mate and lay eggs,’’ Duthie said.

Besides stopping the bug from arriving in the country, the other major weapon in MPI’s armoury is the ‘‘samurai’’ wasp, which is a natural parasite in Asia.

Duthie said New Zealand had created waves internationally when the Environmental Protection Agency pre-approved the release of the wasp last year as a bio-control measure. ‘‘The EPA has agreed that if we have an incursion of the stink bug, we could release this parasitoid into the environment to help eradicate it. Normally you only get permission to release a bio-control once the pest is established.’’

If anyone spots a stink bug, they should contact the biosecurity pest and disease hotline on 0800 80 99 66.

Lobby group 50 Shades of Green is worried about pine forests blanketing productive farmland.

‘‘Last season we intercepted 3483 at the border.’’