Ramped up biosecurity controls have done a good job of keeping the dreaded brown marmorated stink bug out of the country. But should the one-dollar-coin-sized bugs gain entry to our greener pastures, the Environmental Protection Agency (EPA) has pre-approved the release of their traditional foe: the pin-head sized samurai wasp.
The bug has decimated crops in North America and poses one of the most significant biosecurity threats to our agricultural sector – particularly the kiwifruit and wine industries. It also has the potential to attack native plants like karaka and kowhai.
The EPA’s decision means they are only able to release the non-native samurai wasp if stink bugs slip through the border and invade. The samurai wasp is not the only biocontrol agent we have at our disposal. The EPA has previously released other parasitic wasps to control the agricultural pests like clover root weevil and coddling moth. However, this is the first time the EPA has got preapproval to release a species into the country ahead of a threat, an advance the agency’s organism manager Stephen Cobb told Newsroom was “ground-breaking”.
“Bio-control is increasingly what the primary sector and people focused on conservation are looking at as it is considered possibly a bit more environmentally friendly than the use of pesticides or herbicides or chemicals,” said Cobb.
New Zealand winegrowers biosecurity manager and emergency response manager, Dr Edwin Massey, who is also a member of the Brown Marmorated Stink Bug Council previously told RNZ the samurai wasp is both a surveillance and control tool.
“The wasp favours brown marmorated stink bug eggs over any other stink bug egg, so releasing it only when there is a stink bug incursion is exactly the right thing to do.”
The Ministry for Primary Industry’s Dr Catherine Duthie told Newsroom: “We’ve got quite an arsenal lined up. This parasitoid [samurai wasp] is just one of those tools.” MPI is also preparing pheromone-laced traps to lure the stink bugs, a spray to kill them, and trained dogs to locate areas with bug infestations.
“Essentially the parasitoid is a mop-up measure to make sure that we don’t get any further adult or nymph brown marmorated stink bugs into the population.”
The decision has been covered by local media, including:
RadioNZ: Approval given for wasp to be used if there is a brown stink bug invasion
Newsroom: Samurai wasp ready to take on stink bugs