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Hunting Poachers Remotely

New technology uses metal detectors in the wild.

The closest that park officials often get to catching poachers is stumbling across carcasses days or weeks after the culprits have fled the scene. Now a new surveillance system may help locate, track, and intercept poachers before they strike.

Catching poachers: The TrailGuard metal detectors are buried next to forest trails that are used by both humans and animals. A poacher carrying a machete or a rifle will trip the detector, which will send a radio signal to a nearby Internet gateway and then to the Internet via satellite. With real-time data, park rangers have a better shot at intercepting illegal hunting.

The system consists of a network of foot-long metal detectors similar to those used in airports. When moving metal objects such as a machete or a rifle trip the sensor, it sends a radio signal to a wireless Internet gateway camouflaged in the tree canopy as far as a kilometer away. This signal is transmitted via satellite to the Internet, where the incident is logged and messages revealing the poachers’ position and direction are sent instantly to park headquarters, where patrols can then be dispatched.

“[This system] is a force multiplier,” says Steve Gulick, an electrical engineer and director of Wildland Security, a Brooklyn-based organization that develops antipoaching technology. “It could potentially make the patrols more efficient. They would know where to go and could mount a real-time response.”

Since the early 1990s, Gulick, a self-confessed “biologist wanna-be,” has been using his talents to develop gadgets for biological research and conservation projects. A couple of years ago, Gulick developed motion-triggered cameras for biologists studying chimps’ tool use in the Nouabalé-Ndoki National Park (NNNP) of the Republic of Congo. The surveillance system, dubbed TrailGuard, is his latest project. Gulick was inspired to develop the system after watching, frustrated, as “patrols returned time and again without any apprehensions–but with bags of animal body parts.”

The U.S. Fish and Wildlife Service is funding the first field test of TrailGuard within the Goualougo Triangle–the southernmost corner of the NNNP. The site is a prime locale for studying chimps and is unusual because, according to researchers currently working there, it has remained intact and free from hunters for hundreds and possibly thousands of years. “We have not found any indication of illegal entry and poaching in the study area where we are habituating wild chimpanzees,” wrote Crickette Sanz and Dave Morgan in an e-mail from Congo. Sanz is an anthropologist at the Max Planck Institute for Evolutionary Anthropology, in Leipzig, Germany, and Morgan is a field researcher with the Bronx-based Wildlife Conservation Society, in New York.

But, they say, the area could be threatened by illegal hunting as logging operations move closer: the research team has already identified signs of illegal entry in a region just north of the Triangle.

“This indicates that consistent surveillance and long-term protection efforts are needed in even the most remote areas,” wrote Sanz and Morgan.

The tropical forests of the Congo Basin are geographically vast, remote, and impossible to patrol for illegal bush-meat hunting, say the researchers. Park-ranger patrols in tropical Africa often rely on intelligence information from informants, which can be unreliable or outdated. Even if the information is accurate, the timing of missions and regions targeted by patrol units rarely intersects with poacher activity.

The problem, says Gulick, is that the parks are understaffed. The Nouabalé-Ndoki National Park, for example, covers an area of 400,000 hectares (roughly 1,500 square miles). Yet only about 15 rangers man the area, says Gulick. “The patrols are infrequent and random, and the probability of catching poachers is almost zero.”

Because the vegetation is dense, both people and animals tend to traverse the parks via well-established trails. Gulick’s metal detectors are designed to be buried in the ground along these trails. Two detectors buried about 100 meters apart reveal the direction in which the poachers are headed. To avoid false alarms, the detectors only respond to ferrous metals such as iron and steel. Aluminum tent poles, for example, wouldn’t trigger a response. The sensitivity of the devices can also be fine-tuned so that items such as pocketknives slip by undetected. Rangers and other park personnel who need to carry rifles would carry a device that would signal their identity to the detectors.

Many other groups have also expressed an interest in using Gulick’s system. James Gibbs, a conservation biologist at the State University of New York (SUNY) College of Environmental Science and Forestry, in Syracuse, thinks that TrailGuard could be a valuable tool for protecting the heavily poached snow leopard in the Altai region of Central Asia, as well as the giant tortoises that inhabit the Galapagos Islands.

“With vast tracts of wilderness, trapping poachers is like looking for a needle in a haystack,” says Gibbs, who met Gulick while working in the Altai and invited him to SUNY as a visiting scholar. “But TrailGuard could improve the efficiency in the [park rangers’] response. There would be less poking around in the dark.”

“I don’t think it will solve all problems,” Gibbs continues. “There may be issues with deployment, data collection, and ramping up the production [of the sensors]. But it could potentially change the nature of interactions with poachers.”

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