
The "devil's cactus": An invasive cactus called Opuntia, or prickly pear, is tearing through the wildlife-rich grasslands and ranges of Laikipia County in Kenya.

Rapid spread: The cactus is spread by wildlife eating its fruit and dispersing the seeds, but any part of the cactus that breaks off is liable to take root and grow.

Injured elephants: Elephants snack on the fruit of the invasive cactus but can ingest sharp spines that lodge in their mouth, stomach lining and intestine, causing painful abscesses.

Human-elephant conflict: The relentless spread of the cactus close to human settlements is causing a spike in human-elephant conflict.

Waging a war: Locals have been waging a war to control the prickly pest for years, but with limited success. Mechanical removal risks spreading the cactus further if parts of the plant break off and re-root.

Dangerous spines: Opuntia is particularly hard to manage, due to its dangerous spines. They can injure humans and wildlife.

An invasion: The cactus has invaded more than 500 square kilometers of Laikipia County.

Bugs: Biocontrol is said to be the best way of managing the pesky cactus. That involves releasing cochineal insects that feed on the cactus, killing it off.

Inaccessible areas: The spread of the prickly pear is dense in many areas, making them inaccessible by foot or vehicle.

Drones: Drones are being used to map the spread of the invasive cactus and the success of biocontrol efforts.