Poisoned mice to be dropped on Guam to kill invasive snakes
Millions of non-native brown snakes now live on this Pacific Island and have wiped out at least 9 other species.
Mon, Feb 25, 2013 at 10:46 AM
Photo: Armed Forces Pest Management Board
Guam has a snake problem. As many as 2 million non-native snakes now call Guam home, an invasion that started back in WWII when snakes started hitchhiking their way to the island aboard airplanes and ships. The invasive reptiles, mostly brown tree snakes, have wiped out nine of Guam's 12 native bird species and much of its other wildlife. They also have a high cost on Guam's human population: they bite people and also disrupt power lines on a regular basis.
Now the U.S. Department of Agriculture (DOA) is preparing to take the snake problem this unincorporated U.S. territory by the tail. The agency's solution: bombarding the island with thousands of dead mice laced with acetaminophen, the active ingredient in painkillers such as Tylenol. Humans take acetaminophen for headaches, but snakes that eat the drug-laced rodents will die. Officials don't hope to kill every snake on the island in the process, but they say it will be a good step toward controlling the snake population.
The mouse-drop is scheduled to take place in April or May, at which time the dead rodents will be strapped into tiny parachutes — actually streamers — before they are dropped, one at a time, over the island's forests. The parachutes aren't intended to break their fall but the streamers will hopefully snag them in the trees where the brown tree snakes reside and like to eat.
The strategy has a few things going for it. For one thing, brown tree snakes don't mind eating dead animals as long as they aren't too dead. The DOA figures the dead mice will only be appetizing to the snakes for two or three days, after which Guam's tropical climate will make them, shall we say, less than appetizing.
For another, there really aren't that many other animals left on Guam to accidentally eat the poisoned mice. William Pitt of the U.S. National Wildlife Research Center's Hawaii Field Station told the Associated Press that there was initially a concern that crows would eat the mice, but "there are no longer wild crows on Guam." The critically endangered Mariana crow used to exist on Guam but has probably been extinct there since last year, according to BirdLife International. (A few dozen of the birds remain on nearby Rota island.)
While Guam's wildlife is unlikely to recover even if brown tree snakes are eradicated, the effort is designed to protect another set of Pacific islands: Hawaii. Hawaii, known in some circles as "the extinction capital of the world," already has an invasive species problem that is wiping out its native wildlife, a situation that the potential arrival of the brown tree snake would make even worse.
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