Anti-poacher drones will complement rather than replace sniffer dogs and teams of armed, GPS-tagged rangers connected by a digital radio system, BBCNews reports.

Interest in anti-poacher drones is global and rapid advances in drone technology will play a significant role in anti-poaching and wildlife conservation, according to the report — but only as part of an integrated, ground-to-air tracking and surveillance system.

A low-cost drone competition — the Wildlife Conservation UAV Challenge — has received nearly 140 entries.

The winners will be announced in November, and their drones will be tested in South Africa’s Kruger National Park.

“Kruger National Park is ground zero for poachers,” said Crawford Allan, spokesman for the World Wildlife Fund’s crime technology project. “There are 12 gangs in there at any time. It’s almost like a war zone.”

A Kenyan 90,000-acre reserve, Ol Pejeta Conservancy specializes in protecting white and black rhinos. Ol Pejeta has teamed up with San Francisco-based tech Airware, which makes drone autopilot systems.

“With the blessing of the Kenya Wildlife Service we did 10 days of testing,” said Robert Breare, Ol Pejeta’s chief commercial officer, in a BBC interview.

Park rangers can operate the drone via two laptops, one showing the drone’s point of view through a high-definition camera and the other showing a map tracking the flight path.

Thermal imaging cameras mean the drone can also fly at night, with the operators able to differentiate the shapes of animals.

Based on testing, they can even see how the elephants’ trunks changed temperature as they sucked up water from a trough.

With a wingspan of less than a meter, the catapult-launched test drone flew at an altitude of about 500 feet.

“You hardly see or notice it,” Breare said. “We don’t want to startle the wildlife… or the tourists.”

Killing rhinos for their horn and elephants for their tusks is a multi-million dollar business with Asia driving demand. The trade is threatening Africa’s wildlife tourism industry.

A kilogram of rhino horn sells for around $60,000 while a large horn can fetch $250,000, Breare said.

But drones are not a silver bullet, Breare said. “Trying to find the small shape of a poacher in a 90,000-acre park is still difficult, even with high-spec nighttime and thermal imaging.”

Smaller, cheaper drones come with a typical battery life of 30-to-90 minutes, but large game reserves “really need drones that can fly for six to eight hours,” Breare said.

Airware estimates that drones for anti-poaching will cost $50,000 to $70,000. Higher-specification long-range drones could cost $250,000 or more.

On an African plain in the dead of night, poachers can be invisible to rangers just 100 meters away.

So hand-launched drones with night vision can provide a very useful extra pair of eyes, said Scott “LB” Williams, founder and director of the Reserve Protection Agency (RPA), a nonprofit technology consultancy.

But even when poachers are located, GPS-tracked rangers have to arrest or chase them away. Gangs are often funded by organised crime syndicates and heavily armed. It’s dangerous work.

About 1,000 rangers have been killed over the last 10 years trying to protect wildlife, the Game Rangers Association of Africa estimates.

“We’ve designed our own tracking tag incorporating RFID (radio-frequency identification) technology and attached it to animals, rangers, vehicles, weapons and trees,” Williams said. “We’re putting up three large towers to pick up the tag signals and creating a kind of cyber canopy. The (drone) is just one layer of the onion, not the whole solution.”

The WWF’s crime technology project has also been trying out this approach after receiving $5 million in funds from Google.

“Our ultimate finding was that drones by themselves were pointless,” says WWF’s Crawford Allan. “The first thing you do need on the ground is well-equipped, well-trained rangers to react to the data coming in. Other systems – such as tagging and tracking of animals – used in combination with UAV tech makes much more sense.”

Until then, Allan says: “Nothing beats a real dog.”