Maui’s Ant-Sniffing Sleuth
by Lisa Truesdale
Freddie, a highly trained black Labrador retriever, is Maui’s first line of defense against invasive little fire ants. Working with the Maui Invasive Species Committee, he helps protect crops, native species and ecosystems across the island.
photograph by Maui Invasive Species Committee
The newest employee at the Maui Invasive Species Committee (MISC) arrived from Australia last May – ready to get to work alongside his new teammates.
When he’s not on the clock or honing his specialized skills, Freddie enjoys long walks, backyard zoomies and collecting rocks, leaves and shoes to carry to his kennel. Freddie, who recently turned three, is a highly trained black Labrador retriever – and Maui’s first dog capable of detecting invasive little fire ants (LFA).
Highly invasive and barely visible, little fire ants are one of Hawai‘i’s most destructive pests – harming people, pets, agriculture and native ecosystems. On Maui, early detection is critical to stopping their spread. That’s where Freddie comes in. With a nose trained to sniff out even the faintest ant scent, this energetic black Lab is MISC’s newest – and perhaps most adorable – line of defense.
LFA aren’t native to Maui – or any Hawaiian island. They were first detected on Hawai‘i Island in 1999 and on Maui in 2009, in Waihe‘e. Experts at MISC believe the ants likely hitchhiked from their native Central or South America on potted plants. They’ve also been found in mulch, irrigation tubing, building materials – even used cars.
Despite their tiny size – about half a sesame seed – LFA deliver a painful sting that causes welts lasting for weeks. And disturbing them is all too easy. Clouds of ants can be blown out of trees and onto unsuspecting humans below. In pets, stings have caused corneal damage and even blindness. In agriculture, LFA devastate crops and destroy beehives by attacking larvae.
Large infestations are expensive and difficult to control – which is why Freddie’s role is so important.
“Freddie works in a variety of environments,” said handler Trisha Dillenburg. “He’s accurately detected scent-imprinted materials – like paper or bark that little fire ants have walked over, leaving their unique scent behind.” Recently, he even learned to detect ants treated with an insect growth regulator – a nontoxic solution that sterilizes queens and gradually collapses the colony. “Now that Freddie can detect those, we can better monitor treated sites to ensure no live ants remain,” she added.
MISC is part of a statewide response coordinated with the Hawai‘i Department of Agriculture and the Hawai‘i Ant Lab, which developed the baiting and treatment methods now used across the islands. Community involvement is also key – residents can help by reporting suspected infestations and participating in neighborhood treatment efforts. In one major success, a 175-acre infestation in Nāhiku was nearly eradicated using a combination of bait treatments and helicopter applications of insect growth regulator – proof that coordinated action can work. In 2023 alone, MISC surveyed over 1,000 properties and treated hundreds of infested sites, with Freddie helping cover more ground faster and more accurately than human teams alone.
Freddie – whom Dillenburg describes as “goofy and quirky” – isn’t allowed to interact with other dogs, in case he picks up unwanted behaviors. He enjoys people, but Dillenburg keeps fan interactions to a minimum to avoid distractions. “It’s hard,” she admitted, “because he is cute.”
Otherwise, he’s a lot like any other dog. “He’s athletic, happy, curious and extremely play-motivated, with a touch of stubbornness,” Dillenburg said. “Those qualities make him excellent at scent detection – and a lot of fun to work with.”
