Experts eye natural ways to control ants
As Christchurch residents fight booming ant populations, researchers are working to find a natural control of the pests.
Residents across the city, including in New Brighton and Mt Pleasant, have taken to social media this summer to express their frustration at an increase in ant numbers.
Victoria University professor of biology and ant expert Phil Lester is part of a team studying populations to help find alternative ways to lower pest numbers. Lester was in Christchurch on Monday sampling Argentine ants, which are a "major international pest".
Populations of Argentine ants at Riccarton High School, on Tuam St and at New Brighton beach are among those being sampled across the country's entire distribution for the nationwide project.
"We're trying to find ways of natural control of these ants," says Lester.
With a team at The Institute of Environmental Science and Research (ESR), called the Virus Hunters, last year a new virus was found in the Argentine ants.
"From here, we hope to do some work to see if it is really harmful or not."
Lester says on a long-term scale, the research has the potential to limit the need for extermination methods and pesticides.
Argentine ants were likely to blame for the city's issue because they were "the most problematic in New Zealand", he says.
Argentine ants have been present in Christchurch, the southern-most point of their existence, for several years, he says.
"I'm not sure if we took them out of an urban environment they'd be able to survive. They need the warmth humans provide – and cities tend to be warmer points."
Cleaner Megan Thomson wakes up every day and wonders where ants will crop up in her Aranui home. She says the problem has been getting worse over the last two years.
Ants have taken over Thomson's kitchen, garage and have even been found in her bedroom wardrobe.
"They do cost you on so many levels and they cost you time as well," she said.
Despite meticulously cleaning her house, leaving bait out and hiring an exterminator, the ants are finding their way into any sealed and packaged food.
"You have to be on the ball all the time... you can't have a lazy day."
Lester said the movement of people and their possessions post-quake was contributing to the problem.
"These ants will nest in pot plants and that sort of environment, so they will be moved around a lot more like that," says Lester.
He said exterminating ants was an effective way to lower populations but it needed to be done collectively by neighbours so they did not "re-invade" properties.
Advice to lower Argentine ant numbers:
- Prevention is much easier than cure, so if you're moving house, be very careful with what you move - for example, pot plants. If you're coming from an Argentine ant-infested problem, don't take the problem with you.
- If you have Argentine ants already, then get the neighbourhood together for control, rather than tackle the problem by individual house.
- Be clean with your food.
- The Press