Argentine Ants Invasion

A plan has been prepared to try and control Argentine Ants that have invaded a pocket of largely industrial land on the south side of Blenheim.

The Argentine Ant, as distinct from the more common Darwin Ant, is considered a highly invasive pest in some parts of the country and is a particular nuisance when it infests the recreational spaces in parks and reserves. They have become a major horticultural pest in some warmer parts of the country.

These ants were first reported in Blenheim nearly a decade ago in the area of Park Terrace and since then they’ve become established in a 20-hectare pocket of land bounded by State Highway One and the railway line, to the Opawa River and along to Stuart Street. The majority of the area is the industrial area around Main Street, rather than housing.

This species of ant is known to be well established in Nelson and its thought that may be the source of Blenheim’s infestation.

The Council’s biosecurity team is planning to arrange the use of surface sprays and insect baits to try and stop the insect spreading to other parts of our region. Council staff and contractors will treat the area using BiffAnt® surface spray, Biforce® granules and Xstinguish® ant bait.

The Council will be seeking the support of all landholders in the treatment area and they will be contacted directly to discuss the treatment plan.

The Argentine Ant is very similar in appearance to the Darwin Ant as both are light brown in colour. However, Darwin Ants give off an unpleasant odour when crushed - unlike Argentine Ants.

People living near the affected area who think they may have Argentine Ants on their property are invited to contact the Council or bring a sample in to be checked.

It’s intended that the control programme will begin in October.