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Metal detectors spring poachers

African elephant

New technology to catch poachers may mean that elephants aren't so vulnerable when they stop for water (Image: iStockphoto)(Source: iStockphoto)


A metal-detecting sensor that can be buried alongside often-used trails can help identify poachers' weapons and alert authorities.

The TrailGuard system is soon be installed and tested in the Nouabale-Ndoki National Park in the Republic of Congo.

It could also significantly reduce the unnecessary death of elephants in Africa, snow leopards in Russia, giant tortoises in the Galapagos Islands, and jaguars and peccaries in Costa Rica.

"There is a major determent factor to just having a security system in place," says inventor and electrical engineer Steve Gulick, a visiting scholar at the State University of New York College of Environmental Science and Forestry, and director of Wildland Security.

The plan, says Gulick, is to use local knowledge about poaching routes and bury a dozen 25 centimetre sensors along these paths.

"In the Congo there are clearings in the forest that have salty water that the elephants particularly like. These are poaching hotspots," he says.

Although the routes are known and well travelled, it's impossible to patrol them 24 hours a day, seven days a week.

"And even if you could, poachers could circumvent the sentries," says Gulick.

The sensors detect metal up to 3 metres away, sending a radio signal into the area to determine whether the metal is coming from security patrol guns or someone else.

Guards carry transponders that respond to the radio signal with a signal encoded with an identification number. When the buried sensor receives the authorisation code, it takes no further action.

But if the device doesn't receive the code, it goes into alert mode. The sensor sends a second signal to a radio gateway, a cube-shaped device concealed in the treetops.

The gateway beams the signal to a satellite, which transmits it to a ground-based station and along the internet to a designated computer server.

In just a few seconds, the database at the server records the event and then alerts a list of registered recipients.

Among those on the list are security personnel, who can dispatch a patrol to intercept the source of the metal.

Park funders can also receive the signal, says Gulick, which could increase donor confidence that the money they're spending for patrols is actually being used.

Although such a system could help overcome funding problems, the technology needs time to iron out the bugs, says Dr Iain Douglas-Hamilton, founder of Save the Elephants in Nairobi, Kenya.

"I would suggest deployment in a limited area where there is a highly effective management presence to take advantage of the new technology. Then if can be proved to work well in these circumstances it would naturally be more widely adopted," he says.

'Limited area' by African standards is still fairly large, however. In the Congo's Nouabale-Ndoki National Park, TrailGuard will monitor elephants across nearly a million acres (about 400,000 hectares) of land.

Tags: environment, computers-and-technology, engineering