Wild eye

Wildlife rangers in African and Asian parks have it rough these days. Outnumbered, out-funded, and sometimes outgunned, they battle roving gangs of poachers who indiscriminately kill elephants and rhinos and saw off their tusks and horns for fast cash. Ivory tusks can sell for $1,000 per pound on the black market, and often end up as statuettes in China. Many rhino tusks make their way to Vietnam, where people grind them to powder and eat them in hopes of curing cancer. They are worth nearly $30,000 per pound.

Some rangers have a new weapon in their arsenal: In South Africa late last year rangers launched drones into the skies above the 7,500-square-mile Kruger National Park. Using heat-sensing technology, the drones detect illegal hunters and beam their location back to ranger headquarters. The spy planes arrived at a crucial time: Poachers killed a record number of rhinos in South Africa last year—668, up from just 13 six years ago. Most were killed at Kruger.

Last June the World Wildlife Fund announced it would begin using drones costing about $2,500 each to monitor rhino and tiger poaching in Nepal. Ol Pejeta Conservancy in Kenya, home of four of the world’s last seven northern white rhinos, plans to launch a drone in March that will travel up to 50 miles per flight, scanning the ground by day or night. Conservationists in Kenya are also fitting some elephants with collars equipped with GPS and accelerometers that will send out an alert if the elephants stop moving or behave erratically.

Unlike many military drones, the robotic craft used by rangers are small. They can be launched by hand and are relatively inexpensive. They aren’t a foolproof solution, though. Damien Mander, founder of the International Anti-Poaching Foundation, reported that his team crashed one of its drones three days after introducing it to Niassa National Reserve in Mozambique, ripping off its wings. Software glitches plagued his fleet, too.

Some conservationists say the drones have been oversold. “We need to see results before we allocate resources,” a spokesman for the Kenya Wildlife Service told an Al Jazeera reporter. “We need to know whether poachers are capable of bringing drones down, just like they can bring down other aircraft.”

But a drone has already bagged four suspected poachers at Niassa: The aircraft’s thermal imaging camera picked up the embers of a fire, revealing the suspects’ campsite to rangers, who arrested them.

Weapon finder

While drones hunt for poachers on the savanna, police hunt for handguns in New York City, where concealed carry permits are rare. Their latest tool is an expensive scanner as bulky as a washing machine, mounted on a tripod or truck, that can detect a handgun beneath clothing 30 feet away. The “T-Ray” scanner measures terahertz radiation, a form of electromagnetic energy humans emit naturally. On the scanner’s display, any object blocking the radiation, such as a gun, is highlighted on a person’s body. The device raises the possibility of indiscriminate scanning of citizens. Police Commissioner Ray Kelly said the scanner would only be used under “reasonably suspicious circumstances.” —D.J.D.