The project -- organised by the US Department of Agriculture (USDA) Wildlife Services -- sees tablets of paracetamol inserted into dead mice, which are then used to poison brown tree snakes.
The drug-laced mice are dropped from helicopters with miniature parachute devices, consisting of two bits of cardboard linked by a long ribbon of paper. This ensures the mice get stuck in the tree canopies where the snakes are rather than tumbling to the floor where they could be eaten by other native species.
Some of the mice are planted with radio transmitters to determine whether they have been eaten or not. Researchers can then find and collect the dead bodies of the snakes that have eaten the mice.
Paracetamol is safe for human consumption but is deadly to the snakes because it prevents their haemoglobin from carrying enough oxygen. A child’s dose of the drug will cause a snake to go into a coma and die.
The brown tree snake is one of the only snakes that will scavenge as well as hunt -- most snakes will only eat prey they have caught themselves.
It's a tree-dwelling species indigenous to Australia, Papua New Guinea and a number of Pacific islands. It was mistakenly introduced to Guam after World War II and it has since caused serious damage to the island’s ecosystem -- causing the extinction or near-extinction of several native species. They have also caused more than 1,000 electrical outages from when large snakes come into contact with power lines.
Up until recently, most of the snake control strategies in Guam have focused on stopping the snake from spreading to other nearby islands such as Hawaii. This latest technique tackles the snakes literally head-on in their jungle territory.