Dead mice loaded up with poison have been dumped out of an airplane above the island of Guam, as part of an ongoing effort to eradicate an invasion of tree snakes that's hurting the island's prosperity.
The mice corpses have been filled with 80 mg of acetaminophen, in relatively low does that would require a cat to eat 15 of the things to suffer any ill effects. Some of the mouse bodies were further defiled by the addition of radio transmitters, allowing scientists to know if they were eaten by the snakes or left to rot on their own.
As well as being mildly poisonous (comparable to a bee sting, if much worse psychologically), the tree snakes cause a real impact on the country's economy by damaging overhead power lines. Hence the poison plots. [Guampdm via Phys.org]