HONOLULU (HawaiiNewsNow) - A coqui frog's mating call slices silence. Measured at 90 decibels up close, it can reach the sound level of a lawn mower.
The distinctive two-tone KO-KEE chirp belongs to the male coqui, but a copycat whistle belongs to an imposter.
State Agriculture Department land vertebrate specialist Keevin Minami mastered the coqui's call. He is an expert imitator and an adept coqui catcher.
"To find a frog the size of a quarter is pretty amazing," he said. "We wouldn't be able to do it if it wouldn't call back."
Minami and noxious weed specialist Derek Arakaki answer coqui alerts on Oahu. It took them years to perfect the frog's chirping sound.
"We've heard it so many times. We know what the juvenile ones sounds like," Arakaki said.
They capture male frogs because they guard the nest. Without them coqui eggs dry out. A stakeout can last hours, so the men use voice-activated recorders to do an initial assessment and eliminate false alarms.
"We can distinguish if it's a greenhouse frog, coqui, kolea, a fire alarm. Sometimes they call us for that," Arakaki said.
The recorders fit into housing shaped to capture sound. Multiple recorders triangulate the source and zero in on the sender. It's the science of catching coqui.
"When we go out there at night, we kind of know where it is," Arakaki said.
When they show up, they whistle and wait for an answer. But the frogs can fool you.
"They can throw their voice," Minami said. "You might hear it from here but it might be calling from here."
It's tricky. If they whistle when the coqui's calling, the frog will stop and disappear into the night.
"Sometimes it's hard to see. So part of it is training your eye to see movement and color," Arakaki said.
They capture the coqui with plastic tubes and take them back to a terrarium. Minami estimates he has caught 200 coqui on Oahu.
"Patience is very key to this," he said.
Arakaki also does the coqui call, but praises his partner as the real expert.
"To entice them to call we just use one tone," Minami said.
Coqui have overrun the Big Island and saturated it with coqui choruses. Minami said so far that hasn't happened here.
"Our Big Island staff is doing a really good job in inspecting. That's why we haven't had very many reports of coqui frogs," he said.
They've cornered the frogs in backyards, at stores and on school grounds, even in the center of Waikiki at the International Market Place.
"What we're not seeing now is infestations where we get a breeding population, where you have multiple males, females and juveniles, where it almost sounds like the Big Island. A lot of chirps," Arakaki said.
The Wall Street Journal recently wrote about Oahu's Coqui patrollers. The article said Minami communicates with the critters. It called him the "frog whisperer."
"Somebody came up with that name when we were searching for a frog in Hawaii Kai," he said. "I never lived it down after that."
The Agriculture department said Oahu's coqui condition is under control, thanks to nursery owners who inspect their plants, and the coqui catchers who speak the frog's language fluently.
If you live on Oahu and think you hear a coqui frog on your property call 586-PEST.