Four-legged friends could help root out six-legged pests under a growing program to teach dogs on Hawaii island how to detect little fire ants.

Dog training teams around the Big Island are training canines to sniff out little fire ants, after previous successes in using dogs to detect other invasive species like coconut rhinoceros beetles.

The project, by Oahu nonprofit Conservation Dogs of Hawaii, has “about six or seven” dogs able to detect the stinging ants so far, dog trainer Teri Rolph said.

Rolph said she has a passion for canine scent work, a dog sport that trains the animals to detect and locate the source of specific odors, which has obvious crossover benefits for working dogs. Because dogs’ noses are much more sensitive than humans’ — “they have something like 300 million olfactory receptors in their noses, compared to humans who have like 6 million” she said — they can be trained to recognize a wide variety of things based on seemingly negligible traces.

“In the sport world the dogs target certain essential oils,” Rolph said. “Here we start training them on dead ants.”

Once the dogs are accustomed to the scent of the pests, the samples are put into more distracting environs that more closely mimic a real-world setting, such as among foliage or at the base of a tree, Rolph said.

While little fire ants can be dangerous for pets — the ants can potentially blind cats and dogs — Rolph emphasized that these ant-­detecting dogs work safely.

“At this point in their training, they’re not locating a target by burying their face in it,” Rolph said. “They’re on leashes with handlers observing their behavior.”

So far, Rolph said, the dogs that have been trained to detect little fire ants have become reliable at both ­detecting the presence of ants and distinguishing between different concentrations of ants. However, she said the range at which they can detect the ants varies depending on the circumstances, such as the direction of the wind.

Rolph said Conservation Dogs of Hawaii is trying to figure out the most effective use cases for the ant-detecting dogs. While they can be an obvious boon for managing the pests on Oahu, where the ants are less prevalent, they might have more niche uses on the Big Island, where the ants are firmly entrenched in places around the county.

“One thing we were thinking was that they could check nurseries or any place where plants are being moved around,” Rolph said. “Or if you’ve treated an area and waited six months, you could come back with the dog and see if it was effective.”

Big Island Invasive Species Council Manager Franny Brewer said dogs capable of detecting invasive devil weed have been useful at clearing buffer zones around areas known to harbor the weeds.

“With a dog we can clear a buffer zone about two times as fast compared to just using humans,” Brewer said. “It’s not about finding the exact location of the weeds, but it’s more about figuring out priorities. If they don’t detect anything in the buffer zone, then we know we don’t need to prioritize it.”

Brewer agreed the ant detectors would be most useful for businesses where plants are regularly being transported from place to place, to determine the ants aren’t being carried with the plants or soil.

She guessed that they also could be useful for places on the Big Island that haven’t yet been infested with the ants — she said workers at Hawai‘i Volcanoes National Park take great pains to ensure that equipment and materials aren’t harboring the insects, a process that could be expedited with a bit of canine help.