What's different in Auckland
Region-wide control
Auckland's Regional Pest Management Plan lists Argentine ants for sustained control across the whole region, which Auckland Council says is meant to reduce a pest's spread and its impacts. For a colony on your own section, the work still falls to you and a pest business.
Moving plants or gear
Auckland Council says to check potted plants for ants before moving them, and suggests submerging a pot in water for two minutes. It also says to check garden soil, bark, building materials, camping gear and vehicles. That matters most when you're shifting house or giving plants away.
Heading to the Gulf islands
The plan also lists Argentine ants as a Hauraki Gulf Controlled Area pest, so pot plants, soil and gear going out to the islands deserve a careful look first.
Colonies that cross fences
DOC says Argentine ant nests cooperate and can form super-colonies stretching hundreds of metres, and that larger ones may need a coordinated community response. A neighbour with the same trail is no coincidence.
Is it an Argentine ant?
DOC describes Argentine ant workers as 2 to 3 mm and honey-brown, and notes that most other ants you'll see in New Zealand are black. They move in large trails five or more ants wide, close together, and readily climb trees. Auckland Council adds that the queens are dark brown and larger, at roughly 10 to 12 mm.
Manaaki Whenua ranks them highly as a household nuisance in New Zealand: they get into cupboards, sealed jars, electrical areas, behind walls and into beds. DOC says they can bite, too.
Why spraying the trail can backfire
DOC says the wrong amount of pesticide can make an Argentine ant colony split up, which makes the ants harder to control. A surface spray at the back door deals with the ants you can see and leaves the nests that keep sending more.
A pest business will want to find where the trails start, how many nests there are, and whether they cross into the neighbours' sections. That decides the product, where it goes and whether a follow-up visit is needed.
What you can do, and what to leave
You can
- Wipe up sweet spills and crumbs, and keep sugar, honey and pet food sealed.
- Follow a trail outside and note where it goes.
- Check pot plants and garden soil before moving them.
- Talk to the neighbours: you may share a colony.
Leave to a pest business
- Choosing and placing a product that reaches the colony.
- Ants that have moved into wall voids or electrical areas.
- Coordinating a shared colony across several sections.
Questions to ask first
- Which product will you use, and how does it reach the nests?
- Will you treat the whole section, or only where we see ants?
- Should the neighbours be part of it?
- When will you come back to check?
Where we'd start with ant control in Auckland
We'd follow the trail outside before doing anything else, and see where it goes. If it heads over the fence, we'd have a word with the neighbours. Then tell us Ants with where you're seeing them, and leave the spray can alone until a technician has had a look.
Want someone to look at it?
Tell us what you've seen and your postcode, and a local pest business that handles exactly that calls you to talk it through.
