It would be no exaggeration to say that the establishment of the yellow-legged hornets could trigger an economic and ecological crisis of epic proportions.
Why are they so deadly?
The yellow-legged hornet - known as the Asian hornet overseas - is an apex predator that can kill 30-50 honey bees a day. Not only are our honey bees affected, but our native insects, most not found anywhere else, have evolved without such predators, and are poorly equipped to defend themselves – the risk to our biodiversity is immense. We only have to consider the wasp invasions last century to see how bad it can be.
Why so bad for the economy?
The honey industry would be affected at least as badly as when varroa were accidentally introduced 25 years ago; which increased the costs to maintain each hive, increased annual loss of hives and beekeepers leaving the industry. The biggest threat to us though is pollination.
Pollination adds about NZD two billion annually to the New Zealand economy; insects that pollinate our crops include honey bees, bumble bees, native bees and others.
Crops that depend upon pollination include fruit and vegetables, seed crops, and pastures and their ancillary industries like grazing – dairy, beef and sheep.
MPI’s SOPI report projected over NZD 8 billion annual export revenue from horticulture up to June 2025; almost half of which is kiwifruit, and a billion dollars from apples and pears. These pollinating insects enhance quality and quantity of fruit set, without which our horticulture industry would struggle to remain competitive
Not only could a disruptive pest like this affect our economy but it will upset our biodiversity and reduce so much of our native fauna, which could then affect our native flora too. Hornets are quite aggressive, with deaths overseas from hornets caused by anaphylaxis. Their stings are longer than a honey bee’s and they can spray venom, so the traditional beekeeper’s suit doesn’t provide sufficient protection.
All in all, any cost to ensure that they don’t gain a foothold in New Zealand would be money well spent, we don’t want to look back in ten years and question what else we could have done.
What can be done?
While some believe that MPI have dropped the ball on this one, I disagree. I’ve seen firsthand the ramping up of our response. As an AP2 with NZBB (New Zealand Bee Health & Biosecurity) and having participated in other honey bee biosecurity protection I’ve seen the passion and participation of everyone involved.
Extensive trapping and surveillance by MPI is key to containing this threat. If more nests are found then stricter yet proportional measures will be enacted. Aucklanders’ response has been phenomenal, searching their gardens and green spaces for hornets and nests and reporting anything suspicious. People I’ve spoken to have been cautiously optimistic. We only have a year or two to eradicate them before they become established here. With a concerted coordinated effort it is achievable – and a timely reminder just how fragile and precious our ecosystem is here in New Zealand.
Ken Brown
Apiculture Tutor Land Based Training Ltd.
President Auckland Beekeepers Club
