Nature & Environment

Poisoned Mice Dropped from Helicopters on Guam

Catherine Griffin
First Posted: Feb 22, 2013 03:08 PM EST

It's not raining cats and dogs; it's raining poisoned mice. Dead mice laced with painkillers will be dropped from helicopters onto Guam's jungle canopy. Why? Officials hope to tempt a species of snake that has caused quite a few headaches for the U.S. territory for more than 60 years.

The brown tree snake was first introduced to the island when it hitched a ride from the South Pacific on U.S. military ships shortly after World War II. They're usually only a few feet long, but can grow to be more than 10 feet in length. Since the snake was first introduced, it has thrived, eating eggs and decimating Guam's native bird species. Because the snake is a nocturnal, tree-based predator, it has met with wide success in the thick jungles of Guam. So far, it has contributed to causing the extinction of most of the territory's birds.

Currently, there are about two million of these snakes slithering across Guam's landscape. They've destroyed natural populations of wildlife, bitten residents and even knocked out electricity by crawling onto power lines. Yet this new method may help cull the population of snakes.

The mice bombing has been years in the making. In order to keep the rodents laced with painkillers from dropping all the way to the ground where they could be eaten by other animals, researchers have developed a device with streamers that are designed to catch in the branches of the forest foliage. This would keep the dead mice suspended and provide an attractive food source for the snakes.

So when will dead mice rain from the sky? The air drop is scheduled to start in April or May. Until then, the residents will have to continue to deal with the snakes.

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