Armies of aggressive argentine ants have invaded the Kāpiti Coast, killing birds and climbing people's legs.

Residents of Raumati South, north of Wellington, are hatching a battle plan to wage war on the pests, one of the most invasive ant species in the world.

The suburb was under attack from millions of the ants, who had spilled into houses and cars, Raumati South Residents' Association chairman Trevor Daniell said.

"There are properties just flooded with them. You just brush against a tree and they fall out."

"The ants travel in columns four or five wide and scatter when disturbed, running up arms and legs aggressively.

"They just gradually take over and spread and spread. Two people have got them in their cars so they could be dropping out all over the district."

The association had called an urgent community meeting to set up a coordinated system of home-made bait stations around the area.

"The only way to control this major threat to our lifestyle is to cooperate as a whole community."

Argentine ants established themselves in Auckland in 1990, and are considered to pose a biosecurity and human health risk. Highly competitive for resources, they kill other species and can bite humans.

Entomologist Richard Toft said the species created "super colonies" where, instead of a single nest, multiple nests cooperated to find food and defend their territory.

"There have been reports of them eating trapped lizards that are skeletonised in hours."

Unlike other ants, they did not run away if disturbed, instead crawling on to humans unlucky enough to get too close, he said.

"If a person disturbs a nest, next thing they'll be 

covered in thousands of ants running up them."

Greater Wellington Regional Council spokesman Stephen Heath said staff had found the ants in Raumati South and planned to run a control programme on the public land.

The ants were seen along the the first 50 metres of the Te Ara O Whareroa cycle trail, and on several cabbage trees at the start of the route, he said.

"We plan to go back for another inspection, particularly now that they appear to also be in Glen Rd."

Action Property Services pest eradicator Maarten​ Lintern​ said ants in general had become a Kāpiti-wide problem due to the warm weather, and argentine ants were difficult to wipe out.

"They form colonies of multiple nests that can cover areas of up to a square kilometre, and they're all interconnected.

"You kill one nest and, because it's only one cell of the actual colony, they reinhabit very quickly."

Eradication was something best left to the experts, who used the most effective products, rather than home remedies, he said.

"You hear people saying to use citrus, but ants eat citrus – they live in lemon trees."

KĀPITI'S MOST WANTED

* The honey-coloured argentine ant measures 2 to 3mm long and forms large nests which can expand to super colonies.

* They travel in large, distinctive trails, often five or more ants across, and will travel over an object, rather than around it.

* Unlike other ant species, they don't give off an odour when crushed.

* If you have a colony that matches the description, call the regional council or the Ministry for Primary Industries.