Guam is full of snakes. So many snakes, in fact, that they threaten the native bird population.

But the United States Army has a strange solution for the snake problem: bomb them with poisoned mice.

The brown tree snake was introduced to the island shortly after World War II, hitching a ride on naval vessels, and in the decades following, managed to kill off 10 of the 12 native bird species on Guam, reports io9. The remaining two species currently live in protected areas guarded by snake traps.

And while the snakes are probably not going to be completely eradicated from Guam, scientists are desperate to stop their spread to other islands, in particular, Hawaii. If the brown tree snake were to make it to Hawaii, it would cause massive damage. A National Wildlife Research Center study from 2010 found that the snakes would cause between $593 million and $2.14 billion in economic damage if they became established, as they currently are on Guam. Most of this damage would come from power outages caused by the snakes. The snakes could hop stowaway on a boat to Hawaii, or even more troubling (though hilarious), they could climb into the wheel wells of airplanes bound for the islands.

So to quell Guam’s brown tree snake population, in the hopes of keeping the snakes from colonizing Hawaii, the U.S. government will drop dead mice laced with acetaminophen (the active ingredient in Tylenol) from helicopters. The snakes have no problem eating already-dead prey, and acetaminophen is deadly to the snakes, although obviously harmless to humans.

The Department of Defense, as well as the Department of the Interior have supported perfecting the mouse drop technique for over a decade. Government scientists have even devised a special flotation device with streamers, so the mice will be caught in the trees, keeping the bodies off the ground where other predators could eat them.

Some were worried about poisoning other animals by the mice, although the snakes themselves solved that problem.

“One concern was that crows may eat mice with the intoxicant,” William Pitt, of the U.S. National Wildlife Research Center’s Hawaii Field Station told the Associated Press. “However, there are no longer wild crows on Guam. We will continue to refine methods to increase efficiency and limit any potential non-target hazards.”