The coqui frog is slightly larger than an inch long, with color ranging from light yellow to dark brown, according to the Hawaii Invasive Species Council. Its distinct, two-note call sounds like “co-qui,” which gives the frog its name. Photo provided by Hawaii Invasive Species Council

Lori Buchanan and the Molokai invasive species staff got a call about a suspected coqui frog in Kalae at around 10 p.m. on June 20.

“We went out to investigate and we could hear a single male calling frog,” Buchanan, coordinator for the Molokai Maui Invasive Species Committee, said Tuesday. “We located it, luckily, and we controlled it.”

Buchanan is reminding Molokai residents to be on alert after the latest discovery of a coqui frog on the island. The infamous invasive species has established itself in places like Maliko Gulch on Maui and Hilo on Hawaii island, agitating residents with incessant nightly calls.

The frog is slightly larger than an inch long, with color ranging from light yellow to dark brown, according to the Hawaii Invasive Species Council. Its distinct, two-note call sounds like “co-qui,” which gives the frog its name. With no natural predators, the frogs spread easily, and in addition to annoying humans, they also eat huge quantities of insects, depriving the native ecosystem of important services such as pollination.

The male frog discovered in Kalae was sitting in an agave plant, Buchanan said.

“I would expect that because they tend to like smooth surfaces that capture water in between,” Buchanan said. “The area we found the frog in is at a higher elevation . . . so there’s more rain here than the lower levels.”

Because the females don’t make a calling sound, they’re harder to locate, and Buchanan couldn’t say for sure whether there were more. However, she noted that “we didn’t hear a cacophony of frogs.”

“Molokai has no naturalized populations that we know of, and so the frogs that we found, they’re just single frogs,” she explained.

It’s not the first time coqui frogs have been discovered on Molokai. In 2001, a coqui frog arrived in a plant shipment from an off-island nursery, according to a MoMISC news release. In 2007, a coqui arrived in roofing material from a big-box store that Buchanan said was located near an infested site. Coqui frogs also came in plant shipments in 2010 and 2012, as well as in a truck bed carrying leaf litter in 2011. All were products from outside Molokai and all were transported by people, as is often the case with invasive species, Buchanan said.

Buchanan said MoMISC staff are trying to trace the origin of the latest frog. She said the person who reported it may have purchased a plant that came from Hawaii island.

“Hopefully they’ll be anomalies,” she said. “Our response is to increase public education and awareness for frogs, so the community can be our eyes and ears.”

The coqui frog can sometimes be confused for the smaller greenhouse frog. Unlike the two-note “co-qui,” the greenhouse frog’s call is a soft chirping like that of a bird or cricket, according to MISC. While the coqui is heard at night, the greenhouse frog is seen during the day. It’s also smaller — about the size of a dime with mottled skin.

Buchanan is determined to catch invasive species early on and willingly gives out her personal cell number on flyers and in news releases.

“When we get calls like this, we respond immediately because prevention, of course, is key,” she said. “Once they get established it’s nearly impossible. . . . The cost to control is astronomical.”

Despite having no state agricultural inspector, Molokai has managed to avoid many of the invasive species that have taken hold on other islands, including coqui frogs, little fire ants and miconia. MoMISC has petitioned the state Department of Agriculture for an inspector, “but we understand funding is very tight,” Buchanan said.

Even if goods are inspected before they’re shipped to Molokai, the products “go right back into areas that are unsecured,” Buchanan said, adding that the invasive species can latch on to anything from vehicles to equipment during the transport process.

“The pathways to get here are wide open,” she said.

“Don’t import plants and materials from known infested sites without thoroughly inspecting them and washing them,” Buchanan cautioned. “Seeds can be so small that they can come from hunters hunting on one island, equipment being used on one island. And, of course, plants is No. 1 because the animals love to live in them.”

Oftentimes pests are introduced by people, so Buchanan reminded residents to be aware when traveling to and from infested areas. She thanked the community “for being observant and calling,” thus far, and said that all reports are anonymous.

For more information, visit molokaiisc.org or mauiinvasive.org. Residents who think they’ve spotted a coqui frog or other invasive species can call the statewide pest hotline at 643-PEST. On Molokai, call 553-5236, ext. 6585 or 336-0625 to reach Buchanan. On Maui or Lanai, call 573-6472.

* Colleen Uechi can be reached at cuechi@mauinews.com.