“We’re going to be in watch mode essentially forever, because the ants are going to keep coming from the Big Island unless we’re able to stop them,” Maui Invasive Species Committee Manager Teya Penniman said Monday. “While people haven’t reported finding any more (in the last two months), the reality is they’re out there. We just don’t know where they are.”

Penniman said the committee was receiving calls about the fire ants for the first few weeks in January, though the calls have “fallen off” since February.

State Department of Agriculture officials were able to trace the infestation back to hapuu, or Hawaiian tree fern, shipments at Lowe’s Home Improvement and at Home Depot. Customers who bought the plant from either store in 2013 were instructed to check their homes for the pale orange ants.

The non-native species, which has been a problem on Hawaii island since 1999, is only as large as a grain of sand, and two colonies with queens could be in a space as large as a golf ball. They may inflict painful stings on humans, blind pets and pose a threat to Maui’s visitor and agriculture industries.

Penniman said her committee received about 10 calls in the weeks immediately after the ants were discovered, “but more than 10 hapuu went out” from the two Maui stores.

By now, the ants have likely moved on to other areas or plants, although Penniman said there is still a chance to keep the species contained with the diligence of residents and, possibly, the help of trained canines.

A bill currently moving through the state Legislature would provide more than $500,000 toward efforts to eradicate the little fire ant, including a canine detection team pilot project. House Bill 2469 awaits a hearing before the House Finance Committee.

Penniman said the county has already invited specialists from Australia who have successfully trained dogs to sniff out the little fire ants. She said they are scheduled to visit the Valley Isle in May to share their techniques.

In the meantime, she urged residents to be diligent when buying or shipping things from the Big Island.

“We really need to keep that awareness up long term,” Penniman said. “You have to pay attention to what you buy, ask where it came from, ask what they have done to test it (for little fire ants).”

The state Department of Agriculture, which employs eight inspectors on Maui, has been focusing its efforts on intercepting ants coming in on shipments from the Big Island. The most recent infested shipment they intercepted on Maui was in early February, a department official said.

“We set up surveys at the ports, which is what we do regularly anyway,” said Neil Reimer, acting administrator of the state department’s Plant Industry Division. “We find them sporadically, and we destroy those shipments and then follow through with the Big Island staff and let them know which nursery has been infected.”

He mentioned cut flowers as one of the most common items the ants have been found on.

The department is still relying on the public to help contain the invasive species by calling in reports of sightings. He said the state department has also gotten significantly fewer calls in recent months.

“There’s still a huge threat, and a very serious threat,” Reimer said. “It’s a small stinging ant that can come into homes, drop out of trees and sting you, that’s not what you want. Plus the impact on agriculture and pets, it’s not a good bug.”

To check for the presence of little fire ants, residents can smear a little peanut butter on a chopstick and put it near the base of a live fern or other suspect plant. Leave it there for at least half an hour. By then, there should be a number of different ant species on it.

Put the chopstick in a sealed plastic bag and put it in the freezer for a day. The freezing kills the ants. Residents should then call Agriculture Department officials, who will send an inspector to investigate further and, if necessary, treat the area to get rid of the ants.

These copper-colored ants are only 1/16th of an inch long and should not be confused with the larger tropical fire ant, which also stings and has already established itself on Maui.

The Agriculture Department’s Plant Quarantine Branch in Kahului can be called at 872-3848. It is open weekdays from 7:45 a.m. to 4:30 p.m. The Maui Invasive Species Committee phone number is 573-6472.

An educational video about little fire ants may be found at lfa-hawaii.org.

* Eileen Chao can be reached at echao@mauinews.com.