An invasive species of venomous ant has taken up residence in Kaua'i, Hawai’i, where residents are now enduring one of the most extensive infestations in the island’s history. Numbers are estimated to be in the millions, marking the worst infestation since the insects were first detected in the region back in 1999.

Electric ants, also known as little fire ants (Wasmannia auropunctata), crossed the Pacific by hitching a ride on imported goods. According to Spot The Ant, Stop The Ant, little fire ants are included in the worst 100 invasive species on the planet by the International Union for Conservation of Nature Invasive Species Specialist Group, owing to the fact that their numbers can boom to such an extent that it becomes almost impossible for people and wildlife to avoid getting stung.

"They're changing the way of life for our residents here in Hawaii," Heather Forester of Hawai'i Ant Lab said to SFGATE. "You used to be able to go out hiking and go to the beach. They can rain down on people and sting them."

The severity of the current infestation boom was realized in Wailuā River State Park, in eastern Kaua'i, where a colony made up of millions of insects was found. As their numbers increase, so too does the chance of them invading people’s homes, with reports already coming in of residents being stung in their sleep.

As venomous insects, electric ants deliver a sting that causes immediate and severe pain, though this shortly subsides. However, it’s followed by inflammation and the development of painful lesions that can linger for days or even weeks.

As well as harming people, they can blind animals including cats and dogs. They also have a negative impact on agriculture, both in the harm they cause to workers and the fact that they encourage plant pests and deter the beneficial species that normally keep their numbers in check.

The goal now is to try and contain the spread, with a special focus on preventing the insects from reaching water. This is because they can use waterways to disperse across great distances, making their spread even harder to control.

In Hawai’i, little fire ants have been detected on Kauaʻi, Oʻahu, Big Island, Lana’i, and Mau’i. If you suspect there may be some scuttling nearby, the Hawaii.gov website has some tips on how you can help.

“If you see this species on any island, call 643-PEST and/or visit 643pest.org. Survey for ants on your property and test all materials you bring home including, but not limited to, mulch, plants, agricultural products, and construction materials.”

For further information on the infestation, and advice on contributing towards their eradication, check out the The Hawaiʻi Ant Lab, a program from the University of Hawai‘i Pacific Cooperative Studies Unit dedicated to managing the spread of little fire ants.