JOHANNESBURG — Standing in his flatbed truck, Marc Goss touches ‘‘take off’’ on his iPad 3, and a $300 AR Drone whirs into the air. It’s his latest weapon to fight elephant poachers near Kenya’s Masai Mara National Reserve.
‘‘It’s an arms race,’’ said Goss, whose green khaki clothing shields him from thorny acacia branches in the 74,000 acres of savanna he protects. ‘‘We’re seeing larger numbers of poachers.’’
Besides the almost 2 foot-long drone, Goss and other conservationists use night-vision goggles and Google Earth in an effort to halt the decline of Kenya’s wildlife, which helps attract $1 billion a year in tourism. With elephant ivory sold for more than $2 per pound in Hong Kong, Kenya faces its most serious poaching threat in almost a quarter-century, according to the United Nations.
At least 232 elephants had been killed this year through Sept. 30, adding to 384 last year, from a population of 40,000. Demand for illicit ivory from expanding economies such as China and Thailand has doubled since 2007, according to the UN Environment Program.
The patch of land monitored by Goss borders the reserve, where seminomadic tribesmen known as the Masai herd their cows. On a warm morning he was in the hills above the village of Aitong. Fifty-five yards away was the body of an elephant, minus her tusks, surrounded by 10 grieving family members.
Poachers had speared the pachyderm in her back. The carcass was the third found in four days, an unusually high number, Goss said. The ivory would be worth more than $8,000 in Asia.
‘‘It’s pretty grim,’’ Goss said. ‘‘It’s an elephant without a face. It’ll be eaten by hyenas now.’’
Goss, 28, a Kenyan, initially thought the drones would help mainly by providing aerial footage and tracking poachers armed with rifles, as well as the Masai, who sometimes kill elephants when they interfere with cattle grazing. He soon discovered that the drones could help by frightening the elephants, keeping them out of harm’s way.
‘‘We realized very quickly that the elephants hated the sound of them,’’ Goss said. ‘‘I’m assuming that they think it’s a swarm of bees.’’
His team has also put collars with global positioning system devices on 15 elephants so they can be tracked on a computer using Google Earth. That way the animals — who have names such as Fred, Hugo, Polaris, and Madde, after Goss’s wife — can be followed to see if they’ve strayed into areas at risk of poaching or human conflict.
Goss hopes to buy 10 more drones and to modify them by adding a mechanism that releases capsaicin, the active component in chili pepper, when elephants stray near dangerous areas. Paint balls loaded with chili pepper are being used in Zambia’s lower Zambezi region to deter elephants from high-risk zones.
‘‘Drones are basically the future of conservation. A drone can do what 50 rangers can do,’’ said James Hardy, a fourth-generation Kenyan and manager of the Mara North Conservancy. ‘‘It’s going to reach a point where drones are on the forefront of poaching. At nighttime we could use it to pick up heat signatures of poachers.”
Kenya is proposing stiffer penalties for the slaughter of elephants and rhinos, and the government has deployed paramilitary forces and plans to acquire drones to fight poaching.