Fire Ants Are Invading Hawaii, so Helicopters Are Blasting Them With Birth Control

The ants are blinding pets and torturing farmworkers: “It was like a whole piece of my body was getting lit on fire.”

HAWAII — Hawaii has a really big, little problem: invasive ants. Two species — yellow crazy ants and little fire ants — are taking over the islands, destroying their native biodiversity, and making life miserable for residents. Scientists have struggled to eradicate what are considered some of the world’s worst invasive species.

Hawaii’s rugged terrain and dense jungle make ants almost impossible for people to eliminate from the ground. Now, scientists are unleashing a new tool: helicopters dropping ant birth control. It's the first time conservationists are spraying a non-toxic bait from helicopters to stop ants from reproducing, and it could provide a successful model for other places trying to control invasive bugs.


But it’s not a silver bullet. If the helicopters miss any ant infestations, the bugs could quickly proliferate again. So nature lovers are also training dogs to sniff out the tiny invaders and advance the ant assault on foot.

The stakes are high. Both ant species wreak havoc on native plants, animals, and insects. Yellow crazy ants spray formic acid that disables their prey, wiping out native species like nesting seabirds, endangered yellow-faced bees, and other insects. The ants invade seabird colonies and engulf their bodies, causing malformed beaks, a loss of webbing on their feet, and difficulty breathing.

Both ant species can also cause blindness. Little fire ants have blinded pet dogs, cats, and farm animals. Yellow crazy ants cause skin irritation in birds that can blind them.

And all of this is likely to be exacerbated by climate change. As the environment warms, the ants will be able to move into higher elevations as well.

“We're going to continue to lose all of these extremely special and amazing species as yellow crazy ants expand their range,” U.S. Fish and Wildlife Service biologist Sheldon Plentovich said. “We really have to figure out a way to control them or we're not going to have anything left.”

And little fire ants also sting humans. Since the ants don’t grip trees very well, they fall off branches and “rain” down on people who brush through vegetation. This can mean potentially hundreds of ants stinging a human at the same time, causing welts and a burning sensation that can last for weeks. They plague farmworkers in particular.

“It was like a whole piece of my body was getting lit on fire,” said Mikia’ala Pua’a-Freitas, a native Hawaiian and Maui Invasive Species Committee member. She manages a property that is now infested, so she began as a field crew member for the ant eradication.

“It was a no-brainer to help be a part of the solution to eradicate these pests, because not only are they harmful and they hurt, but from a Hawaiian’s perspective, it could forever change the course of the way we live here in our homeland.”